The information contained herein,  is solely for the use of EXABYTE
customers.  It is not intended for distribution beyond the internal
use of our customers.


                         LIBRARIAN
                EXB-8500, 8500C, 8205, 8505
                    FIRMWARE CHANGE LIST 
                    AND CODE ENHANCEMENTS

The Code History provided in this document begins with 8CC-0472
released December 2,1992 through 8CC-0447 released June 12,1992.

12/02/92  8CC-0472  CC010472\KS020850
=====================================

CARS ADDRESSED:

S/V-459: Possible decrease in compression ratio.

- Adjusted compression ratio calculation reporting, to insure
report accuracy.  

C-555: Failure on test unit ready. FSC=AC

- In the event of a hardware failure performing a load operation,
the correct report is FSC 0xAD indicating servo hardware error. 

CODE ENHANCEMENTS:

- In the event of a write abort condition,  the drive can perform
a stop SCSI, to prevent a hang condition.

- Enhanced the erase measurement command interface to servo. No
functional change.

- For Half High 3 LED systems, the SCSI bus reset will be indicated
by all three LEDs.

- Enhanced End of Media (EOM) operations for request sense.  This
will support changes for logical partition while performing mode
select operations.














11/20/92  8CC-0471  CC010471\KS020830
=====================================

CARS ADDRESSED:

S/V-458: Bus hang on a verify command. 

- Enhanced set up for the space to reposition operation.   

CODE ENHANCEMENTS:

- Enhanced hardware error handling.  

CUSTOMER UNIQUE ENHANCEMENTS:

- Enhanced reporting for request sense information.  

11/19/92 8CC-0470 CC010470/KS020820
==================================

CARS ADDRESSED:

C-258: Hang on read in 8500C mode.

- Added code to prevent loading of an extra record.

S/V-1656: Read position failed after drive did not change
partitions in mode select.
 
- Adjusted "fast" read position operations. This change allows a
read position to return 0,  until the partition switch occurs. 


CODE ENHANCEMENTS:

- Enhanced main read and read resume tasks. 


11/19/92  85C-046Z  KC01046Z/KS020810
======================================

CODE ENHANCEMENTS:

- Enhanced servo operations to indicate splice in 8500 mode.



- Added new status (F_PS_HTO) to indicate no valid headers were
detected.  This status change will prevent FSC (95) in 8200c mode. 






11/17/92  8CC-046Y  CC01046Y\KS020810
=====================================

CARS ADDRESSED:

S/V-084:   Read hang in 8500 mode.
S/V-1653:  Bus hang on Verify, no status returned.

- Adjusted read processing for consecutive filemarks.

S/V-099:  FSC 95 in 8200C mode. Motion did not time out on the
track command.

- Adjusted motion by disabling additional servo tracks interfering
on track in 8200C mode.   

S/V-1651: Bus hang on send diagnostics command.

- Adjusted interface between rewind and send diagnostics, 
simultaneously performing a disconnect operation.   


CODE ENHANCEMENTS:
 
- Enhanced directory support in 8200C format.  

- Modified the write read test to be complete when requested by
host.

- Enhanced write processing.  

- Modified conditional compression processing operations. 

- Added option to write operations,  data is not compressed if
option is set.   


11/13/92  8CC-046W  CC01046W/KS020810  KC01046X/KS020810
========================================================

CARS ADDRESSED:

S/V-80: Read hang condition.

- Adjustment to read processing operations.


CODE ENHANCEMENTS:

- Added a reset between interrupts to space operations. This
addition will enhance the status reporting to space command
operations.  


11/12/92  8CC-046V  CC01046V/KS020810
=====================================

CARS ADDRESSED:

S/V-1642 S/V-1643:  Diagnostic tape test: A diagnostic tape
couldn't be generated over a code load or headsync tape. 

Enhanced code for the diagnostic selftest tapes. Now, selftest
tapes can be created by overwriting headsync or codeload tapes.  

C-360: S/W hang (8C).

C-2277: FSC 8C, Task Que Overflow.      

- Adjusted Block Type byte operations.  Added Virtual Readback
Checks at End of Stripe (EOSFakeR's).                             
  

CODE ENHANCEMENTS:

- Enhanced the LEOP (Logical End Of Partition) operations, 
performing a load or autoload to partition 1. 

- Enhanced SPACE 0 operations, LOCATE, and SPACE operations on
blank tape.
 
- Modifications added for processing Write Buffer Parity Errors. 

- Enhanced tape resizing processing while formatting tape. 




11/11/92  8CC-046U CC01046U/KS020810
======================================

CARS ADDRESSED:

C-258: Hang on read 8500C mode.  

- Adjustment made to the main read, and resume tasks.

C-359: Failed on Space. 

- Format error was declared instead of permanent read error. 

K-2957: Hit BOT on FSF 11 01 7F FF FF 00.

- Adjusted a mathematical equation preventing very large forward
searches from transforming to reverse searches to PBOT.  





S/V-062: FSC AC servo software error after cleaning tape inserted
and test started.

- Added code to enable the servo to identify cleaning cartridge
status.  This will determine if cleanings remain on the cleaning
cartridge.  


S/V-439: Write LBOT error FSC B3 does not set deferred error bit. 

- Adjustment made to deferred error operations, in the event of
write LBOT failures.   

S/V-1628: FSC 8C software hang.

- Timer adjustment made in 8200 mode performing timed block space
at PBOT (8200 mode only).  A recovery operation will proceed this
sequence.  


CODE ENHANCEMENTS:

- Enhanced parity error handling.

- Enhanced partition operations,  enabling the request sense
operation to report remaining tape with more accuracy. 

- Modifications to send diagnostics functionality.  

- Correction in 8200C mode,  preventing false FSC 95 reports.  


- Modification to write delay, to enable a write operation on any
amount of data. 

- Adjustment to the distance between LEOP1 (Logical End Of
Partition 1) and PEOP (Physical End Of Partition). 

- Enhancement to sense data operations. 

- Enhanced reliability of software and firmware resets. 

- Enhanced switching operations in write mode.  


11/04/92  8CC-046T  CC01046T/KS020790
==============================

CARS ADDRESSED:

S/V-268, S/V-365 & S/V-377, FSC 8C due to Task Que Overflow.




-Modified method of limiting Virtual RBC's at End Of Stripe.  

K-1626, FSC 95 due to Off Track.  

-It is Required START-STOP write to tape to be long enough to
preclude a subsequent splice. 

S/V-1630,S/V-1631: FSC 0A ILI on a read, FSC 0D filemark on a read.

- Adjustment to mode select switch partition, while a immediate
command is executing. 

C-2293: Write hang asserting busy for 10 seconds without SCSI
activity, resulting in controller timeout.

- Added 8200C stop transfer bus hold, when drive is not active.

S/V-449: Expecting ILI on a verify command.

- This change allows ILI to be generated by a verify command. 

CODE ENHANCEMENTS:

- Added Unsuccessful Cleaning indicator code (UCLN) reporting for
request sense. This addition will indicate cleaning failures.  The
indicator stays on until reset, a good cleaning, or power-up. 

- Modified definition, identifying what Send Diagnostics test to
run.

- Enhancement for performing splice operations. 

- Enhancement to Send diagnostics, creating diagnostic self test
tapes. 

- Adjustment in 8200 mode for PEOT/Forward search. 

- Modification to PARTITIONING format. This change upgrades the
tape resize function for partitioned tapes on 8500c drives (and
8505 drives when resize is implemented).


- Added code for FM/EOD detection in fixed mode. 

- Modified LED routines. (slow, fast, off).










10/30/92  8CC-046S  CC01046S/KS020770
=====================================

CODE ENHANCEMENTS:

- Enhancement to Read operations to avoid possible overrun
conditions.


10/28/92  8CC-046R  CC01046R/KS020770
===============================

CODE ENHANCEMENTS:

- Modification to send diagnostics to report a fault symptom code
of 0xB0. In the event a permanent read error occurs.

- Enhancement to keep track of the last servo commands issued.

- Modified error recovery operations for writing 8200C Long
Filemarks.  Avoiding the possibility of FSC (96).

- Enhanced Mode Sense Data Compression Status page (Page Code=22h)
as referenced in 8CC-046Q.



10/27/92  8CC-046Q  CC01046Q/KS020770
=====================================

CARS ADDRESSED:

S/V-0038: FSC 8C on a Write. 
S/V-1608: Software hang on a Read.

- Modified code to reset after processing BOT operations.

CODE ENHANCEMENTS:

- Added support for Mode Sense Data Compression Status page (Page
Code=22h) in read mode:1). Clear compression ratio counters when
switching from read to write or write to read mode.2). The actual
bytes transferred and read will be supported in the next code build
(46R). 

- Request Sense operations will report if the last cleaning
cartridge used was unsuccessful.   

- Adjustment made when reading/spacing encountered PEOT,  without
an EOD marker on the media.  This will prevent a possible "bus
Hang" condition. 

- Enhanced Inquiry Support to indicate a "Soft" reset
configuration. 


CUSTOMER UNIQUE ENHANCEMENTS:

- Enhanced 8200 mode Space Filemark to stop on blank tape (EOD). 

10/22/92  8CC-046P  CC01046P/KS020740
======================================

CARS ADDRESSED:

S/V-1605: FSC 95, regression test 8523C, 8523CS, 8200, 8200C.

- Modified code to clear positioning retry variables following a
successful CLEANATM operation.

S/V-1615: Bus hang after a read command was sent a no-op message
during the data phase.

- Corrected occurrence of re-enable transfer after receiving a NOP
message,  performing a read operation. Compression only.  




CODE ENHANCEMENTS:

- Enhanced search field variables. 

- Implemented "thread processing" in Send Diagnostic operations.  

CUSTOMER UNIQUE ENHANCEMENTS:

- Report "ready" when a queued tape command is excepted. 

- Changed the type of reset from an 'R' (no CRC) to a 'P' (full
power on tests). 

- Enhancement to software and firmware resets. 


10/16/92  8CC-046N  CC01046N/KS020740
=====================================

CARS ADDRESSED:

C-2274,C-2283 Disconnect in data with NDD.

-Adjustment made in 8200C mode, insuring no-disconnect mode.






S/V-293: FSC 95 Regress test 8523C/8200C.

- Adjustment in 8200C mode, in the event a over shoot occurred, 
performing a position to write operation. This adjustment will
avoid a possible FSC (95).  

S/V-426: Mode select fails with FSC 76 (undefined).

- Modification added to insure a send partition format request is
not sent if a drive is down.    

CUSTOMER UNIQUE ENHANCEMENTS:

- Enhanced Mode Sense select page 10h.  

- Added customer unique EEPROM configuration option. 


10/14/92  8CC-046M  CC01046M/KS020740
=================================

CARS ADDRESSED:

C-323: Unexpected SW hang encountered during a Space in 90H
density.

- Adjusted the retry mechanism by modifying the retry search
direction associated with C-314.


K-2951: FSC 8C on a write filemark.

- Adjusted write operations at LBOT.

S/V-414: After drive was cleaned, amber LED indicator came on. FSC
8C.
S/V-422: After cleaning drive, a data cartridge was inserted. The
amber LED indicated a servo timeout.

- Modified code to wait for the cleaning cycle to complete,  before
sending M_POST_ALERT.


CODE ENHANCEMENTS:

- Enhanced write operations at LBOP (Logical Beginning Of
Partition) 0.  

- Enhanced erase operations for partitioned tapes.

- Modified execution time during the LBOT processing.  The
modifications save approximately 70uSec (a 5% savings).      



10/08/92  8CC-046L  CC01046L/KS020730
=================================

CARS ADDRESSED:

S/V-1602: Adjusted message reporting sent when repositioning in the
event of read abort condition.

C-2276: Adjusted command reject on a STOP HSS.  This change will
prevent simultaneous stop commands from the controller and the
servo.

CODE ENHANCEMENTS:

- Additional Send Diagnostic selftest tape enhancements added.

- Enhanced codeload,  and headsync tape performance.


10/07/92  8CC-046K  CC01046K/KS020730
======================================

CARS ADDRESSED:

C-2243: Raw read hang.                                            


- Enhancements added to control code to suspend data transfer
processing raw read operations.

S/V-294, S/V-299, S/V-1587: FSC 9B, Regression test apendvc/8200C. 

- Modified control code performing physical write processing.

S/V-390: A write was issued at LBOT completing with a good status.

- Adjusted end of media (EOM) setting after a short write.


CODE ENHANCEMENTS:

- Additional development for reading send diagnostic selftest
tapes.

- Enhanced parity error processing.

- Enhanced track capture functions.

- Modified DPW_TRACE operations.   






10/05/92  8CC-046J  CC01046J/KS020730 ===========================

CARS ADDRESSED:

S/V-291: FSC AB Servo timeout on a Read.
- Increased the timeout for BLANKSEARCH.  

CODE ENHANCEMENTS:

- Enhanced customer unique features for (LIMITED) Send Diagnostics
operations.

- Enhanced erase operations for partitioned tapes.

- Enhanced non-buffer mode single azimuth operations. 


10/01/92  85C-046G/8CC-046H  KC01046G/CC01046H/KS020720
========================================================

CARS ADDRESSED:

C-2093: HW error on a Write. FSC=8C
C-2252: HW error on a Write. FSC=8C
C-2258: Check condition error on a Write. 8200C mode. FSC=8C
C-2260: HW error on a Write. FSC=8C

- Adjusted control code settings performing write
suspend/disconnect operations,  in the event the operation is
cancelled before completion.

S/V-386: Failure with FSC 95 

- Modified Space operations while placing data into the backzone. 
This change prevents rereads and locate difficulties if a large
number of gap blocks are encountered. 

S/V-412: Hang on Send Diagnostics command self test 111 with
damaged tape.

- Modified block read operations.  


S/V-1502: Verify command reported an ILI incorrectly. 

- Modified reporting for ILI operations. 


CODE ENHANCEMENTS:

- Enhanced send diagnostic selftest tape operations by adding the
capability to create LBOT.



- Enhanced erase operations for partitioned tapes.  

- Modified code to enhance send diagnostics operations.

09/29/92  8CC-046F CC01046F/KS020720 ===================

CODE ENHANCEMENTS:

- Enhanced erase track variables.

- Additional tape resizing enhancements. 

- Enhancement to Send Diagnostics command to create selftest tapes. 

- Enhanced End of Stripe processing.

- Enhanced parity error operations.



09/28/92  85C-046E  KC01046E/KS020720 ======================

CARS ADDRESSED:

C-2212: Parity error injected during write. Logical record still
written to tape.

C-2218: Records with bad parity written to tape.

C-2266: Verifying position during aborted write due to forced
parity error.

- Added code to writing logical block operations. This prevents the
last logical record from being released until the next write,  or
a flush buffer command. In addition this prevents Logical records
that had parity errors from being written to tape.

S/V-282: Software hang occurred during a read command.

- Adjusted reposition operations in the event a read abort
condition occurs.  

S/V-387: Flush of buffer with write filemark command. 

- Adjusted deferred error operations in the event a write failure
occurs during a buffer flush with write 0 filemarks.  

CODE ENHANCEMENTS:

- Enhanced the message system for MOTION/SERVO operations.

- Enhanced reporting for NOT READY operations.  



CUSTOMER UNIQUE ENHANCEMENTS:

- Enhancement to Mode Select performing AutoLoad operations.


09/25/92  8CC-046D  CC01046D/KS020720
======================================

CARS ADDRESSED:

C-2253: Check condition on a Space operation - FSC 8C.

- Adjustment in operations processing a slow read.

C-2266: Verify position during aborted write due to parity error 
FSC 9B.

- Adjustment to write abort operations processing a parity error.


CODE ENHANCEMENTS:

- Enhanced control code calculation for read / verify processing.


CUSTOMER UNIQUE CODE ENHANCEMENT:

- EEprom modified for customer unique part number. 

- In the event sense key 4 errors are returned, the eject button
will perform a reset.


09/24/92  8CC-045C  CC01045C/KS020720 ===========================

CARS ADDRESSED:

K-2193:        FSC B3 can't write LBOT.
K-2222:        FSC AD on Space.
K-2223:        FSC AD on Write.
K-2228:        Hang on write filemark.
K-2248:        FSC FC head sync lost on write.
K-2258:        FSC 8C.
S/V-026:       FSC 8C during write in 8500.
S/V-377:       Test failed FSC 8C on a write filemark.

- Adjustment to 8200C extraneous Header Available Interrupts
(RBCs).                             
                      






CODE ENHANCEMENTS:

- Added FSCs for partitions.

- Modified the FSC table.

                                            
09/23/92  8CC-046B  CC01046B/KS020720
==================================

CARS ADDRESSED:

C-314: Unexpected SW Hang (FSC 8C) encountered during a space in
8200 density.

- Adjustment to space positioning operations.

C-2245: FSC 8C on a Locate.

- Adjusted synchronization after HSS operation.

C-2270: Hang on a Read.

- Modification to ILI handler processing.  

S/V-281: No status returned on a Verify command. SW hang.

- Adjustment to Read operations by re-enabling data transfer when
ILI is detected, when interface is not idle.  

S/V-390: Test issues write at LBOT then completes with good status.

- Do not report EOM when physically there.

S/V-395: Amber LED is on due to "clean me" status.

- Can not turn off the "clean me" LED on a load operation.

S/V-396: Read hang running IDE exerciser.

- Added a abort indicator to abort transfer in read operations,  in
the event a ILI occurs performing EBD. 


CODE ENHANCEMENTS:

- Enhanced read and write parity status messages. 

- Enhanced status messages for fatal error, space and read to
report buffered read parity errors. 

- Moved Mid Tape Wakeup FSCs.



- Enhanced status messages for parity.

- Enhancements added for resizing partitioned tapes. 

- Adjustment to convert FSC x19 into FSC xA6 in the event a parity
error, and a CRC error are received simultaneously. NOTE: FSC xA6
causes an aborted error.

- Enhanced single azimuth alignment after HSS. 

09/21/92  85C-046A  KC01046A/KS020720
======================================

CODE ENHANCEMENTS:

- Modifications for parity error processing.

- Enhanced Servo operations processing tracking retries. 

CUSTOMER UNIQUE ENHANCEMENTS:

- Enhanced the NOP send diagnostics into test 10h. 


09/18/92  8CC-0469  Cc010469/KS020720 =============================

CARS ADDRESSED:

C-223:         FSC 36 on Space running Test in 8500C mode.
S/V-172:       FSC 8C on Space command in Test.
K-2934:        FSC 8C software hang.
S/V-408:       Soft reset function - position failure (write
protect switch) cannot be reset by unload.

- Adjustments to permanent error handling performing space
operations. 

C-2211: Specification issue: spec stated that the logical position
after an Abort will be before the aborted block. 

- Added commands to space operations to reposition after a read
abort.  

C-2263: Discrepancy in ASCQ status report.

- Adjusted default for FSC of Test Unit Ready (TUR) to Not Ready
(becoming ready if READY is set).  

S/V-382: Amber LED flashing during cleaning cycle.

- Adjusted primary status change to GET CONFIG operations
performing the MC_UNLOAD command.  



S/V-386: Test write failed with FSC 95. 

-  Adjustment to write operations processing a write at the BOT or
EOT side of an 8500/8500C long filemark.  This will prevent new
data from being adjacent to old data in overwrite situations. 

CODE ENHANCEMENTS:

- Enhanced 8200C TRK_BACKHITCH routine operations.  

09/16/92  8CC-0468  CC010468/KS020720
=====================================

CARS ADDRESSED:

C-2247: Write hang - 8200C mode, sync mode 14,696 bytes per block.
C-2250: Write hang.

- Added write is complete command. This will indicate a splice can
be executed (in 8200C mode only).   

S/V-25: FSC 3D in 8500 mode.

- Disregard EODs with BIDs out of sequence if less than 9 are
received sequentially.

S/V-273: FSC B5 - Media error with new tape after cleaning (112m
blank tape).

- Adjusted LBOT processing in the event a abort is received,  to
avoid a switch to LBOT processing resulting in FSC 0x8C.

S/V-379: Software hang FSC 8C on Rewind.

- Adjusted switch partition operations when physical read is in
progress. This adjustment insures the physical read is completed
before switching partitions.  

S-V-381: FSC 8C on Space to EOD.

- Removed declaration of sequential permanent error if no
prefetched blocks appear in the buffer. This will prevent FSC 0x0B.


CODE ENHANCEMENTS:

- Enhanced format operations for partitions. 

- Enhanced rewind/HSS functions for partition operations.   

- Enhanced 8505 partition switch speed adjustment. 




- Enhanced TRK_BACKHITCH routine operations.  

- Added Enhancements for: 

*      ILI detection and processing. 
*      Suspend initiation. 
*      Pack loaded interrupt processing.
*      Repositioning for read command complete operations. 
*      Read command status.    


09/11/92  8CC-0467  CC010467/KS020710 =========================

CARS ADDRESSED:

C-310: Failed a write setmark with drive in 90H density.

- Adjustment to write setmark operations in 8500c density.  A Check
Condition/illegal request, will report for other densities.

S/V-375: Test failed with SK=04;FSC=8C. 

- Added a test to bypass the 0 space test if the _B_FORCEHSS is
set.  

CODE ENHANCEMENTS:

- Enhanced REWIND operations in write mode, performing a memory
dump. 

- Enhanced the  FORMAT1 command to load tape after erase
LBOT/PBOP0/LBOP0 has completed. 

- Enhanced calculation routine operations for measure and erase
distances to track pairs.  NOTE:  A servo change is a co-requisite
to this change. 

- Enhanced write operations for 2 byte blocks in 8200 mode. 

- Added a new "chkdone" routine for reading operations.  

09/10/92 85C-0466 KC010466/KS020710 ==============================

CARS ADDRESSED:

C-298: Failed on command read (8500C).

- Adjusted HM_TRKOFFSET sync in tracking mode.  

S/V-27: FSC 8C during a Read in 8500 mode on Expert.

C-2225: FSC 8C software hang. Check condition on a Read operation.



- Allocated individual variables for AUTOMOVE (CARUMZUG) and
LBOTONLY. 

S/V-346: A forced parity error during status phase causes host to
abort itself. FSC E6-undefined.
   
- Added FSC 0E6h to sense data in the event an abort 'message out'
from the host is issued during 'status in' following a parity error
abort.  

CODE ENHANCEMENTS:

- Enhancement to the PARTED and PARTITION operations.  

- Enhanced interrupt operations for handshake/sync interrupts
performing a GET SENSE BUFFER command. 


09/08/92  8CC-0465  CC010465/KS020710
====================================

CARS ADDRESSED:

SV-238: Bus hang on Read
SV-248: Software hang on Space 

- Modified variables used to determine setmark synchronous point.

S/V-344: With bit 6 off in identify message (disallow disconnect),
drive is disconnecting during send diagnostics test.

- Adjusted NO-OP: The send diagnostic tests which reset the drive
without disconnect prevledge. 

CODE ENHANCEMENTS:

- Enhanced parity error processing.

- Enhanced the OUT_OF_SYNC positioning to LBOT operation.  

- Enhancement to reset operations via the eject button.  

- Modified synchronization for XS_LOST_IN_SPACE operations. 

- Enhanced performance for set up transfer/disconnect operations. 

- Enhancement to MC_TRACK command TRKRETRY variables.  

- Enhanced statuses for the MC_STPATM command. A status of 06 (on
a filemark & cartridge in) will return M_STPATM_DONE.  The 02
status (cartridge in) will return M_STPATM_MISS.  NOTE: This change
requires a change to both the 8500, and 8205/8505 servos.



- Enhanced the TRK_BACKHITCH and SU_TRK_TO routine operations.

- Enhanced tracking retry operations for 8500 drives in 8200 mode. 
 

- The amber LED will flash in the event of a servo time out
performing error recovery operations. 

09/02/92  8CC-0464  CC010464/KS020700 
=====================================

CODE ENHANCEMENTS:

- Enhanced the reporting of ILI detection performing read
operations.

- Enhancement to verify command processing.  

09/02/92  8CC-0463  CC010463/KS020700
=====================================

CODE ENHANCEMENTS:

- Enhancement to slow motion read recovery (8205/8505).

09/02/92  8CC-0462  CC010462/KS020700
======================================

CARS ADDRESSED:

S/V-192: During a space back 3 filemarks, received a not tracking
error FSC AE in 8200C mode.

- Modified the MC_TRACK command.  Adjustment made to the tracking
offset on a 8505 drive in single azimuth mode.

S/V-342: Backspace block at LBOT on new or erased tape returns the
wrong residual.

- Adjusted the residual in space command operations for blank tape.
The high byte of the residual must be 0 on a forward search and FF
on a reverse search.  


CODE ENHANCEMENTS:

- Enhanced pending pack loaded interrupt operations.

- Enhanced ILI and Verify operations.






08/28/92  8CC-0461  CC010461/KS020700
======================================

CARS ADDRESSED:

S/V-24: FSC 95 on write in 8200C mode running Test. 

- Adjusted PSN_2WT_CNT and ITO_SRCHCNT if an 8200C erase checks out
ok (i.e. not a positioning error).  

S/V-243: Bus hung during write command.

- Adjusted the NOP message processing a read or write transfer.

- Adjusted timing for 8200 mode,  processing block space operations
(8205/8505).

- Adjusted search field detection operations processing
OUT_OF_SYNC.          

- Adjusted Search Fields 8200C mode performing a write operation.

S/V-178, 215, 228: Problem computing residual value in 8200
mode/read processing.

S/V-184: 8500 mode - Software hang during a Read.

- Adjusted residual calculation in 8200 mode and processing for
special blocks. 


08/28/92  8CC-045Z  CC01045Z/KS020700
=====================================

CARS ADDRESSED:

C-2203: Hang on rewind after locate to RCD 0 immediate no B_RCQCMD
from locate command.

- Adjusted locate immediate when CURRENT COMMAND BEGUN completes
after buffer positioning.  

S/V-202: FSC AE on a space command
S/V-245: FSC 3B on 8200 mode space

- Adjusted back space block operations for 8205/8505.  

S/V-246: Tape ejected and amber LED flashing on send diagnostic for
unit self test.

- Modified code to report immediately if a post error is
encountered.  This change will report the post error if the tape
load sequence is complete or not. 


S/V-355: If download (write buffer) is in progress and another Host
issues a different command, FSC EB returned.

- Adjusted sense key for interrupted write buffer from illegal
request (05) to aborted command (0B).  

S/V-247: Read position returned the wrong location during an erase
long immediate rather than LBOT.

- Adjustment to read position operations to report LBOT while
processing immediate erase.  


CODE ENHANCEMENTS:

- Enhanced reverse block space operations in 8200 mode.   

- Enhanced 8205/8505 partitioning. 

- Enabled LED in the event a hardware error occurs.  

- Enhanced 8200 write mode operations.

CUSTOMER UNIQUE ENHANCEMENT:

- Issue a GET CONFIG before REWIND/UNLOAD to determine the tape
(cleaning or data cartridge).  


08/25/92  8CC-045Y CC01045Y/KS020690
=================================

CARS ADDRESSED:

C-2213: FSC on a Backspace Block.

- Adjustment made to the ACC processing the block length.  

CODE ENHANCEMENTS:

- Enhanced setmark processing . 


08/24/92  8CC-045X  CC01045X/KS020690 ==========================

CARS ADDRESSED:

C-295: 8200 density fixed read with block blocksize = 40 fails.

- Adjusted request to complete operation, or connect when
processing a information command data phase.  




S/V-234: Miscompare on request sense information bytes after
spacing into a filemark.

- Adjusted residual for 8200 block space forward operations.  

CODE ENHANCEMENTS:

- Enhanced 8200 block space back operations. 

- Enhancement to LOAD IMMEDIATE command performing a switch
partition operation. 

- Added FSC 93h (Skey 0Dh, ASC/Q 00,02) - Detected Physical End of
partition.

- Enhanced performance for error recovery operations.  


08/21/92  8CC-045W  CC01045W/KS020680
====================================

CODE ENHANCEMENTS:

- Enhancement to accumulator operations.


08/21/92  8CC-045V  CC01045V/KS020680
====================================

CARS ADDRESSED:

C-2146: Read hang in data-in phase.
C-2190: Unexpected filemark on a Read operation. 

- Installed a delay in 8200 mode while the loaded interrupt is
pending (write operations).  

C-2184: Read hang.
C-2186: Read hang.
C-2200: Wrote 268 meg 32K records in variable with no disconnect in
data-in 7 minutes. Read
not complete in 3 hours. 

- Returned the reset of SF detection when none detected at the
beginning of holemode. This prevents proceeding to PEOT during
holemode.


CODE ENHANCEMENTS:

- Enhanced partial buffer holemode recovery operations.




- Enhanced M_SLOWDOWN message operations. 

- Enhanced reporting of partition number in mode sense and read
position. 

- Enhanced Capacity by decreasing GAP blocks before and after 8500
Long File Marks.


08/20/92  8CC-045U  CC01045U/KS020680
=====================================

CARS ADDRESSED:

C-2196: Read Buffer and do a TUR FSC=67 until power off.

- Cleared the XL_STATUS byte when Send Diagnostics completes.  This
change will disable operations until power-up.  

S/V-206: 8200 Mode. Space -4 blocks after writing 16 blocks to tape
returned FSC 34 (PEOT encountered).

- Adjustment for back space block search in 8200 mode when LBOT ATM
is detected while stopping.  

S/V-340: Customer Unique Configuration.


CODE ENHANCEMENTS:

- Enhanced timeout period for reselection (compression drives).   

- Enhanced reporting of partition size in mode sense operations.  

- Enhancements for single length Partition Mode Sense page x11.

- Enhancements for long form partition page x11 in Mode Select.  

- Enhanced partition measurement commands.

- Enhanced compatibility for 8205/8505 servo and 8500 control code.


CUSTOMER UNIQUE ENHANCEMENTS:

- Added Customer Unique option for the system configuration.

- Enhancement for Customer Unique LEDs while using a code load
tape.

- Added Customer Unique part number.  





08/19/92 8CC-045T  CC01045T/KS020680 
=====================================

CARS ADDRESSED:

C-2177: Tape capacity 8500C.

- Adjusted Flushing operations when not at Motion Threshold.

C-2195: FSC 99 WOQ fill error - buffer empty.

- Adjusted Flush operations with a Buffer Empty condition.
  

CODE ENHANCEMENTS:

- Enhancement prevents UNDERRUN at Write PBOP0 operations.

08/17/92  8CC-045S  CC010145S/KS020680
=======================================

CODE ENHANCEMENTS:

- Enhanced the SEC_TIMER operations.

- Enhancement for tape format operations.

- Enhanced the retry mechanism for switching to Partition 0
operation. 

- Enhanced detect the EOD of Partition 0 operation.


08/14/92  8CC-045Q  CC01045Q/KS020670 ===========================

CARS ADDRESSED:

C-2175: Send Diagnostics selftest 110 takes 34 seconds from command
to message phase. 

- Enabled diagnostic reset after completing a information command
when disconnected.  

CODE ENHANCEMENTS:

- Added new option for read position operations.

- Enhanced calculations for rewind operations. 

- Enhanced 8200 mode High speed search operations.



CUSTOMER UNIQUE ENHANCEMENTS:

- Enhanced write buffer blocks of length 0.  


08/13/92 8CC-045P  CC01045P/KS020670 ==============================

CARS ADDRESSED:

C-2090: FSC 0C on 81st read. (PTR 5 - C-2062)

- Adjustment to BID operations performing parity error handling.  

S/V-162: Drive hung the bus during a Read operation.

- Modification to perform I_RELEASE if there is any data in the 
buffer, and not suspended in a transfer. 

S/V-196: 8200C mode - uncorrectable block on Read.
  
- Modification to skip holemode processing at filemarks in 8200c
mode.  


CODE ENHANCEMENTS:

- Enhanced partition operations. 

- Upgraded allocation handling and overflow checking. 

- Enhanced MOTION command sequence for writing LBOP0. 

- Enhanced read position operations. 

- Enhanced MC_ABORT operations.  


CUSTOMER UNIQUE MODIFICATIONS:

- Enhanced Immediate Verify operations preceded by a read position.



08/12/92  8CC-045N  CC01045N/KS020670 
===================================

CARS ADDRESSED:

S/V-166: Software hang during Space command.

- Adjusted variables for 8200c holemode recovery, modified buffer
allocation for holemode recovery. 

S/V-194: Software hang during Space command. Space command
disconnected. 8200C mode. 
  
- Added skip of one block in backzone check for 8200C mode.  

C-2152: Customer unique Configuration. Unit attention issue due to
queuing.
      
- Modification superceeds old Unit Attentions when reporting C1 for
Customer unique configuration.  This modification enables C1
reporting only. 

C-2154: After bus device reset message out 0x0C, unit attention
Sk06; FSC C6 is returned until drive starts loading again.
(Customer unique configuration).

- Adjustment reports FSC C7h after SCSI bus reset or SCSI device
reset when tape is in drive. 


CODE ENHANCEMENTS:

- Enhanced addressing operations for partition operations.

- Enhanced detection and reporting operations for PEOP1 (Physical
End Of Partition).

- Upgraded MC_REWIND command operations. 


08/05/92  8CC-045M  CC01045M/KS020670
==============================

CARS ADDRESSED:

C-179: I/O timeout.

- Adjustment to Write Recovery Interrupt Timeouts operations.

SV-165: Expert +WR/RD, 8200 density - FSC 0B, uncorrectable block
on Read.

SV-167: Expert +WR/RD, 8200 density - FSC 0B, uncorrectable block
on Read.

- Adjusted timing for declaring blank tape detected during slow
motion read while processing on Compression units. 

CODE ENHANCEMENTS:

- Enhanced SRCH_PEOP operations. 

- Enhanced M_SPEED setup search timeout criteria. 



08/03/92  8CC-045L  CC01045L/KS020670 =============================

CARS ADDRESSED:

C-2141: ILI error with no residue on Read operation.

- Adjusted ILI interrupt operations  to include the block that
created the ILI the residual count. 

C-2152: Unit attention presented twice under following conditions:
       1.) Mode Select from second Host/TUR from first. FSC C2/C1.
       2.) Power on and load. FSC C0/C1. 

- Adjusted compression and non-compression drives to check for the
SP bit in mode select.  

K-1587: Block space failed on a write filemark E033 medium error.

- Adjusted rewrite distance from 11h to 91h blocks following
Position retry due to OFF_TRACK. This assures that the next splice
will not track across the potentially bad splice.

S/V-160: Disconnect no reconnect after a failure a subsequent write
attempt disconnects with no reconnect.

- Adjusted 8200C write tracking operations.  

S/V-332: After mode select write delay, 64K written and drive
powered off, read of 64k gets blank check or media error.

- Addition to write delay flush operations. Added a I_RELEASE
before the flush is complete.

CODE ENHANCEMENTS:

- Enhanced Data recovery operations. Read.

- Added test operations for formatting a partitioned tape .

CUSTOMER UNIQUE ENHANCEMENTS:

- Modified Customer Unique Configuration for MC_GOBACK command
operations.  


07/31/92  85C-045K  KC01045K/KS020670
=====================================

CARS ADDRESSED:

S/V-320: Drive got Servo software error after power cycle.




- While performing a rewind/unload, disregard a primary status
change, and wait for the command complete. (the unload button was
pressed while simultaneously loading a cartridge). 

CODE ENHANCEMENTS:

- Enhanced Read pack loaded interrupt operations to perform
i_chkdone.  


07/29/92  8CC-045J  CC01045J/KS020650
======================================

CARS ADDRESSED:

S/V-102: Eeprom in 8200 (SCSI 1) image. Inquiry command issued is
not compliant with 8200 IUM.

- Disable access to EVPD in inquiry data when SCSI-1.  

S/V-107: Drive T/O during a write.

- Adjusted logic for reconnect message performing logical read
operations.  

S/V-156: DVT Regression - Host issued a series of write commands
with transfer length of X3E80. 8200C density.

- Adjusted suspend threshold for 8200C write operations preventing
a suspend condition.  

S/V-321: FSC(95) in 8200C mode. Position to write failed after
retries.

- The CLEAN ATM was being issued at a incorrect position.

C-240: FSC 02 running test in 8200C mode. Positioned at BOT side of
a long filemark but also at the EOT side of a short filemark.

- Adjustment for Switch Read to Write operations.  

C-242: Read hang running test in 8200 mode.
C-244: Read hang running test in 8200 mode.
C-245: Read hang running test in 8200C mode.

- Adjusted the signal for an illegal length read operation, to
suspend while more data is put in the buffer.  

C-268: Drive received Software hang when Host issued an Abort
message during a Write.

C-2150: Hangs after aborting Verify command. 


- Adjusted locate repositioning after an abort. (compression only)

C-2089: Clean cycle different from 8500 to 8200 for Customer
unique. 

- Even if the _NAL is set, perform a rewind/unload on an UNLOAD.  

C-2125: FSC D9 on Write in fixed mode.

- Removed test that checks for 160 blocks in 8200 mode read/write. 

C-2137: Write to PEOT leaves incorrect residual count at PEOT.

- Adjusted logical block operations.  

C-2142: Read hang in data-in phase.

- Increment Lblk ID in read abort processing so locate operations
can find the last block successfully read.  

C-2143: Hang during a write filemark operation.

- Added 45 seconds to the CLEAN ATM command.  

CODE ENHANCEMENTS:

- Enhanced external memory operations for diagnostic help. 

- Enhanced Send Diagnostics command operations.

- Added LOC_PARTITION command for locate processing.

- Added B_PREABT, B_POSTABT for tracing compression byte counts
when reading. -

- Enhanced EEPROM options and versions.

- Enhanced trace activity operations processing read transfers. 

- Enhanced partition and locate processing.

- Disabled bad read back check operations.

- Enhanced diagnostic code to read suspend processing.   


CUSTOMER UNIQUE CODE ENHANCEMENTS:

- Modified customer unique Unit Attention operations.  







07/24/92  8CC-045G  CC01045G/KS020640 
          85C-045H  KC01045H/KS020640
======================================
       
C-2140: Hang on a backspace operation.

- Added clarity I_LOC_DONE for 8500 mode abort processing.  

C-2129: Power fail bit 7 of byte 19 on at LEOT.

- Adjusted Reset in USB0 of request sense for customer unique. 

C-2130: Test reads tape and issues rewind immediate command a
request sense command.

- Turn on EOM for Customer Unique when rewind immediate (or load
immed).  

S/V-148: LBOT write failure on a read.

- Added _XB_WAITFLUSH to XB_BITS for accurate processing.  

C-2139: Hit PEOT on a read.

- Adjusted POP/PUSH order, input special operation.


CODE ENHANCEMENTS:

- Enhanced M_SPEED for high speed search operations.

- Enhanced partition operations.  

- Enhanced MID TAPE WAKEUP operations. 


CUSTOMER UNIQUE ENHANCEMENTS:

- Modified status for Space to EOD/blank tape operations. 

- Modified _BLANKSPACE operations for customer unique option
request.

07/20/92  85C-045F  KC01045F/KS020640
=====================================

CARS ADDRESSED:

C-2112: FSC 0A - lengths did no match on a Read. Added a flag so
ILI bit is not checked until
IPORT has started by command.     




- Adjusted compression illegal length handling operations. 

CODE ENHANCEMENTS:

- Enhanced Mid tape wakeup tape format operations.


CUSTOMER UNIQUE ENHANCEMENTS:

- Adjusted Customer Unique Configuration BKGRND_CNTH and
BKGRND_CNTL for CDB processing. 

- Adjustment to full speed processing of interrupts.


8CC-045E  CC01045E/KS020640 =====================================

CARS ADDRESSED:

C-235: Write hang running Expert +W/RD in 8200C mode - B_XFE_R_DONE
but no I_WR_DONE.           

C-323: Write hang. 

- Adjusted 8200c write mode interrupts processing.  

C-241: Once a tape is written in Write Dammit mode, it's always a
write dammit tape - independent of the mode select rewrite values. 


- We now assume that the tape will be written with rewrites (i.e.
clear WRITDAMN). WRITDAMN will then be set if REWRITES is zero. 
WRITDAMN will clear if REWRITES are non zero.      

C-2111: Send Diagnostics self test 110 fails w/Sk=02, FSC=C9 (tape
required and none loaded). 

- Modified Send Diagnostics test 6. 


CODE ENHANCEMENTS:

- Enhanced Motion operations.

- Enhanced Mid Tape Wakeup for implementing the MTW function.

- Enhanced partition read/verify operations.

- Enhanced switch partition search operation.






CUSTOMER UNIQUE ENHANCEMENT:

- Eject tape on successful send diags r/w tape per IUM (customer
unique request).


07/15/92   8CC-045D  CC01045D/KS020640
=======================================

CARS ADDRESSED:

K-2926: FSC 8C during test. 

- Motion sets the broken bit and the errortype (FSC) to AC or AD. 

C-2098: Tape written on 8500 when put in compression unit returns
density code 00; it should return code 5. Inconsistencies present
in EE options.

- Modified definitions for mode select default density. Some
EEPROMS are affected. 

C-2099: FSC AC on a write; attempted to write to PEOT failed after
LEOT with an FSC AC. 
 
- For the turn write servo zones off command, allow a command
reject phase status.   

C-2107: Read hang - completed backup & verify issued rewind read
80.

- Adjusted reset for ILI detection and rewind. 

C-2110: Read in incorrect length test aborts on 4th 1K while only
1K blk written. Data written is incorrect.

- Adjusted AVL_BLKS in the event of a abort at end of the 4TH
record of a write(0C) command. 400H BLKSIZE, 8500 MD. 

C-2112: FSC 0A - lengths did not match on a read.

- Adjusted logical read operations. 


CODE ENHANCEMENTS:

- Enhanced compression illegal length operations.  

- Added DC_SWITCH_PART, and read LBOP commands to switch partition
operations. 

- Added configuration byte for vendor ID number in EEPROM.

- Enhanced compression servo search operations. 


07/09/92  8CC-045C CC01045C/KS020640
=================================

CARS ADDRESSED:

C-2093: FSC 8C - Hardware error on a write operation.

- Adjusted single AZ mode. To prevent data transfer when buffer is
full.

07/09/92  8CC-045B  CC01045B/KS020640
================================= 

CODE ENHANCEMENTS:

- Enhanced Abort operations at LBOT.

07/08/92  8CC-045A  CC01045A/KS020640
===================================== 

CARS ADDRESSED:

K-1561, FSC 9E. 

- Adjusted PLL_PID processing  Position to Write / OFF_TRACK
retries.

CODE ENHANCEMENTS:

- Enhanced read suspend processing. 

- Enhanced EBD block size for compression.

CUSTOMER UNIQUE CODE ENHANCEMENTS:

- Disabled turning off of EBD on odd block sizes option.


07/01/92 8CC-0457  CC010457/KS020640
         85C-0458  KC010458/KS020640
====================================

CARS ADDRESSED:
  
C-230: FSC 95 in 8200C mode running test.

- Adjusted slow speed search operations for Compression drives. 

C-234: Hang on send diagnostic running test.





- Modification in the event a shutdown or rejected tape received
from the rewind operations causes a message to be sent to the
diagnostics manager. (8500, and compression)


CODE ENHANCEMENTS:

- Enhancement to Unit Attention operations.

CUSTOMER UNIQUE ENHANCEMENTS:

- Adjustment to load processing (rewind/unload) commands in write
operations.

- Modification to Log Sense variables.

06/26/92  8CC-0456  CC010456/KS020640 ==========================

CARS ADDRESSED:

C-221: Software hang on Space. 

- Adjusted Search Fields operations.

C-230: FSC 95 in 8200C mode running test.

- Adjustment to illegal length read / suspend operations
(compression). 


CODE ENHANCEMENTS:

- Enhanced synchronous mode operations. 

CUSTOMER UNIQUE ENHANCEMENTS:

- Added option to mode sense /sel EEPROM control processing. 


06/24/92 8CC-0455   CC010455/KS020620
=====================================

CARS ADDRESSED:

C-2063: FSC 9B on Rewind following an aborted Write.

- Adjustment to write abort operations. 

CODE EHANCEMENTS:

- Enhanced compressed record type operations.
  


06/24/92  8CC-0453  CC010453/KS020611
          85C-0454  KC010454/KS020610
=====================================

CARS ADDRESSED:

C-0094, FSC 95: Write current left on during backhitch for write
splice.

- Added 'LASTRDY' operation when Tracking for Write Splice gets
OFF_TRACK. 

K-2906: Write hang during data phase
K-2908: Write hang during Write LBOT

- Adjusted B_REQCMD when disconnected in a write operation. (does
not effect compression drives).

06/19/92  85C-0452  KC010452/KS020611 
=====================================

CARS ADDRESSED:

C-226: Bus hang during 8200 Write.

- Adjusted write suspension operations. (preventing problem for
8200C mode.) 


CODE ENHANCEMENTS:

- Enhanced space operations for slowdown processing.

- Enhanced backhitch values. 

- Enhanced switching operations in compression mode.


06/18/92  85C-0451  KC010451/KS020610
=====================================

CARS ADDRESSED:

K-2563: Incorrect response to SCSI bus parity errors. Errors forced
by ground data line.(Customer unique).

- Adjusted ATN and Parity Error operations to occur at same time
performing a data out phase (ie, mode select).  

C-227: Software Hang (FSC 8C) while executing an 8200 Space.

- Change a hang(8C) into a LOST_IN_SPACE return status.   



C-2056: When error is forced in command phase, drive returns
message in 03. Host sends message out 06. Drive doesn't go to bus
free; it returns to command phase.

- Adjusted message processing after parity error in command phase.

C-2057: Hangs on Write when parity error is forced in data out.

- Adjusted parity error operations at the first record uncompleted.

C-176: Hit filemark on Read.

- After starting a partial write (the first write after exiting
8200C special write mode) clear the low byte of the number of
logical blocks to do.   

C-2039: Test aborts Write, rewinds and reads 1st 4K expecting good
status. Read fails with a media error - FSC 16.

- Adjusted 1K LBLK 8500 mode operations.

C-0097: SW hang trying to Space 1 block (reverse) in between
consecutive setmarks.

- Adjusted space block buffer positioning, when re-positioning a
block between setmarks.  


CODE ENHANCEMENTS:


- Replaced the MTW fault symptom code 0x5A to be a 0x5B. 

- Enhanced splice operations on the EOT side of a SETMARK.  

- Enhanced abort message processing. 

- Updated the ASC and ASCQ values for the Mid Tape Wakeup FSCs. 

- Enhanced partition measurement command operations.  


06/16/92       8CC-0449  CC010449/KS020611
               85C-0449  KC010450/KS020610
=====================================

CARS ADDRESSED:

C-2050: Hang on Write - 8500 mode wrote 637536 KBytes.
C-2051: Hang on Write - 8200 mode both LEDs on.
C-2055: Read hang running HTX with 8CC-0448.
C-2059: Hang on Write after system I/O's. Both LEDs on solid.


- Adjustment to write operations after LEOT has been detected. This
adjustment prevents positioning problems.    

K-2563: 

- Converted read abort to abort due to IDE when appropriate.  The
conversion enhances responses to host detected parity errors. 

CODE ENHANCEMENTS:

- Enhanced Mid-Tape Wakeup EEPROM processing.

- Enhanced backhitch operations.  


06/12/92  8CC-0448  CC010448/KS020611
=====================================

CARS AQDDRESSED:

C-2052: Read hang after 24127 start I/O's.

- Adjustment to read operations. 

C-2047: Write hang 8200 mode - both LEDs on.

- Adjustment to 8200C operations to stop transfer performing a
position to write. 


CODE ENHANCEMENTS:

- Added XB_REJECT_TAPE to the rewind status operations.  

- Enhanced motion status by adding M_LOAD_FAIL.  

- Enhanced autoload operations.  


06/12/92  8CC-0447  CC010447/KS020611
=====================================

CODE ENHANCEMENTS:

- Added M_LOAD_FAIL to the motion statuses.

- Enhanced block type checking routine operation. 

- Enhanced 8200C write filemark processing.


06/11/92 85C-0446 KC010446/KS020610
====================================

CARS ADDRESSED:

C-216: Space to EOD hit PEOT running SCTAPE in 8200C mode. Seed
852.

- Corrected retry mechanism for reading 8200c FM, SM, and EOD. 

CUSTOMER UNIQUE CODE ENHANCEMENTS (NO CARS ADDRESSED):

- Fixed problem in previous change. The sense of the EEPROM option
for EOM at LBOT was reversed. Now, it is fixed. 

06/10/92 8CC-0444 CC010444/KS020581 ======================== 
         85C-0445 KC010445/KS020580  

CARS ADDRESSED:

C-1026: FSC 99 on Write test 8516 writes size records. Test varies
buffer 1 block/CDB 1000 CBD's size=2561.

- Fix to no disconnect code. Bug was discovered while debugging.

CODE ENHANCEMENTS (NO CARS ADDRESSED):

- Add another fix to previous change -- loaded and pack loaded
interrupts were not being disabled correctly and a pack
loaded interrupt was occurring.

06/09/92  CC010443/KS020581
===============================================

CARS ADDRESSED:

C-2037: Disconnect without Reconnect.  

- A Single Azimuth Write did a STOP_XFR for retry of Write EOD
failure which failed with a 95 error. The STOP_XFR condition was
never cleared so subsequently, Write did not respond. The
fix clears XC_BITS3._82C_TRACK for any Single Azimuth Fatal error.

C-2042: Running HTX, SK=04 on Read, FSC 19; Read compression
failure.

- Fix to Abort handling so it no longer destroys the link. 

K-2903: System issues a read command, drive hangs in data transfer,

- Change in Request Sense operation. Now, there is only sense for
each host. Global sense is used when there is no error. This
will prevent interactions between hosts from occuring.  

CODE ENHANCEMENTS (NO CARS ADDRESSED):

- Changed code to prevent multiple B_ABORT messages from being sent
to the command handler when SCSI is aborted multiple times.
This is done by checking to see if an abort is in progress. This
fix will make the managers simplier in the abort handling.  

06/08/92 CC010441/KS020581
         KC010442/KS020580
==============================================

CARS ADDRESSED:
              
C-1088: Read hang 512 byte blocks in compression with pattern
AA,55,00,FFB.
C-2034: Verified that hang problem in CAR C-1088 still exists in
code version CC01043U.

- Add code to fix BENC problem with flushing the last part of a
compressed data on speeds of above 2.5 MB/S.

C-218: Iport fixed to clear zero fill bit in Ben 8040 register
under certain conditions.      

- By ensuring that the zero-fill bit on BEN is off during all
regular read operations.   

C-0076: +Write/Read - failed on Read command.
C-2023: Hardware error on a Read Write pass completed - failed on
Read.

- Modified routine for putting specials in BRT in 8200 mode.
Current code would hang if special (media error) was
declared.

C-0087: Drive failed to return form a read command causing a
timeout.
C-211: SCSI bus hang running +W/Read in 8200C mode.
C-213: Hang on Write.

- Iport needed some changes to keep track of how many blocks were
being written, properly control interrupt handling, and
correctly report status to the write manager. A fix was also made 
to LEOT processing in 8200c mode.

C-216: Space to EOD hit PEOT running SCTAPE in 8200C mode.

- Changed numbering of special types so jump table in space will
work. Special BRT handling.

C-1094: Send Diagnostics self test 2 (10 07 00 00 00 00) fails with
Hardware error. Dump show 1D0000000000 - CDB issued was
1D0700000000.           

- Forced write of non-compressed no-crc data. The compression mode
will be saved and restored after the diagnostic is complete.  

C-219: Backspace block incorrectly gives FSC 32. Hit a filemark on
Space. SCTAPE in 8500 mode.     

- Removed check of XF_BUSY bit. If in write mode we now always do
a rewind without checking if a flush was in progress.  

C-2038: Hangs on Verify command using SCTAPE.

- Another fix for compression verify immediate so that when we
disconnect during a verify immediate (ie, another command to
tape) we give up the BEN for compression. 

C-215: Drive goes to sleep on Verify command running SCTAPE.

- Modifications for verify.  

C-217: SCSI Abort hang SCSI bus - running SCTAPE with seed 367.

- Fix for abort of write when the host sends commands between the
abort and the abort done. This caused a tape command to go into
data phase even though it shouldn't.


CODE ENHANCEMENTS (NO CARS ADDRESSED):

- Added ability to log certain values for diagnostic purposes.

- Moved XD_PASSES to the save area which is not cleared on a reset
so it will be preserved when the drive resets. 

- Added flags for doing the diagnostic write. 

- Fixed bug where we did not read LBOT after a Send Diagnostics
reset. This is because we checked for SD busy, not if just
headsync tape.

- Added slowdown handling for motion. This will tell Dportr that
the search speed has changed from 75x to 10x because of the
approach of a physical tape boundry. Space manager now knows
that the servo is slowing down on a HSS.  

- Fix for dump from the EVT rack. Prevents a disconnect/reconnect
loop when doing the 8200C Stop transfer while positioning to
write. 

- Changed interrupt handling to prevent breaking Verify.

- Clear the FSC if the zero after request sense option
(CF_BITS13.6) when do a GOODSTAT.

- May hang on Verify immediate. Only affects Verify immediate in
compression code. 

- Initialize log threshold data on Send Diagnostics reset.

- Changed code to give bus back to Iport if disconnect on
status/command complete and doing a verify. This allows
immediate verify to work.

- For Request Sense, report log sense threshold page/parameter # in
bytes 15-17. Otherwise, in 8 and 9.

- If broken or soft_brok, report machine sense in request sense.

- Added Log Select functionality.

CUSTOMER UNIQUE ENHANCEMENTS:

- Clear all bytes of request sense when CF_BITS13.6 option is set.

- Force UA on other units when doing a predictive UA (CF_BITS7.3
option with busy). This is to fix a customer unique UA problem
where we won't get an UA on other initiators for C1 (tape
changed).

06/03/92 8CC-0440 CC010440/KS020581
=======================================

CARS ADDRESSED:

C-2021: Filemark detected on read BEN3 non-compressed.

- While adding code to fix a problem with ILI, a bad LID had
deleted a line of code which caused the BRT pointer to point
to the wrong byte. This resulted in bad BRT type hang.

CODE ENHANCEMENTS (NO CARS ADDRESSED):

- Added code to fix a problem with reading all data before a
FM/EOD.


06/02/92 85C-043Y KC01043Y/KS020580
======================================

CARS ADDRESSED:

C-0088: Motion failed on command Space. Drive continued to try to
Space after I/O timeout.  

- Prevent reverse searches from going into an infinite loop if they
read more than 2 meg after a High Speed Search backward. The 2
Meg limit should only have been used for forward searches. 

K-2097: FSC 8C - Hang on a Read.

- After an FSC 3A, the force HSS flag was set which was causing an
8200 mode block space to go out if it was the command following
the 3A space. Now the block space will check the buffer if
FORCE_HSS is set and there is data in the buffer and will return a
MEDIA ERROR if there is no buffered data. 

C-2001: Read data miscompare caused by bad data being written from
buffer afterall aborted write caused by a forced SCSI bus
parity error.

- Forced an iport Write Abort command when a parity error occurs
even if iport has completed the write. 

CODE ENHANCEMENTS (NO CARS ADDRESSED):

- Added 130H to IPORT and 30H to M8500 in two bank compression code
to fit some fixes in. 

- Changed a couple of commands which did not assemble correctly
after some changes to another module.           

05/29/92  043V  043V/KS929570
=========================================

CARS ADDRESSED:

C-205: SW-HANG on Locate CMD running SCTAPE - FSC 8C was not
reported to the Host.

- Locate LID search position correction.

C-208: Software hang PC=2E57 when trying to reset the drive using
the eject button following a servo error.

- Fixed code to use GEN_RESET when a BENC problem occurs. The drive
needs to reset from the button under certain circumstances (such
as certain death) and we need to make sure we can tolerate a
bank switch to 0 when we do it. There is a function in FUNCTLIB
that allows this.  

C-2021: Filemark detected on read BEN3 non-compressed.

- Added code to fix a problem with bad LID and Filemark detected
prematurely. This problem could have caused CRC errors in some
cases.

K-1557: Block Space (read only) failed on Space, E034 hardware
error, FSC 8C.

- Removed use of the REVERSE bit outside of high speed search
operations since it is also used by the fill manager in using
search fields to do holemode searches.  

K-1560: Motion failed on command Space.

- Fix to abort of the fill manager before doing back space block.

K-172: Write Hang with Customer controller.

- Fix for 8200 mode space. Bid position code was leaving flag set
which can cause an 8C if a mode switch is done before the bit is
cleared by a space operation.  
             
K-2011: FSC 8C on Space EOD 8200 mode BEN3 drive.

- Fixed synchronization after search in 8200 mode. SET_ID
synchronization was being attempted when 8200 mode does not
support setmarks.  

K-2096: Sense byte 2 not correct.

- Changed criteria for using machine sense instead of saved sense
(for request sense cmd). In fix of 5/6/92, used the FSC to
determine whether or not to allow machine sense. Changed to use   
the machine sense key and only return machine sense if there is no
host error pending and if the sense key is less than 2 (ie, no
sense or recovered error). This puts it back to where it was   
before 43F (as good as it was plus a little improvement -- no UA to
the wrong host). Use an EEPROM option to clear old sense data
for a host on multiple req senses.

CODE ENHANCEMENTS (NO CARS ADDRESSED):

- Added abort messages to write filemark and rewind managers. They
still don't abort but need to know in case they were in the
process of disconnecting. 

- Added bit flags for the rewind/load/unload manager to handle it's
communications with busif correctly.  

- Added handling for delayed receipt of B_CCB_ACK so we can handle
cases where the rewind completes before busif can do it's job. 

- Added abort message handling. Still don't abort but if an abort
occurs while disconnecting we won't get discon done so we act
like the abort is a disconnect done(B_CCB_ACK in this case). 

- Added abort messages to write filemark and rewind managers. They
still don't abort but need to know in case they were in the
process of disconnecting. 

- Added abort message handling. Still don't abort but if an abort
occurs while disconnecting we won't get discon done so we act
like the abort is a disconnect done. 

- Put in code to generate EC# from the EEPROM instead of the
code itself. Now, can change 8 bytes of the EC# (the
remaining 2 must be blanks).

- Changed hard-coded constants for determining whether or not a
schedule should be put in the mail trace or not. These constants
caused SCSI interrupts to be placed in the mail trace in      
4-bank code. Now, we use the location of the operating system from
database instead. (only affects tracability, not
functionality).

- Change NO_BLOCKS timeouts to 1/8X and 1X for 8500 and Compression
HW respectively.

- NO_82BLK always clears BLKTIMER to reinitialize timeout flag for
sequential commands.

- Correct overwrite of ECC count in external memory caused by log
sense compile flag.

- Fixed problem of forezone count decrementing to -1 after pack
loaded interrupt. Also fixed LEOT processing when in 8200c
mode.  

05/29/92    8CC-043U  CC01043U/KS020571
====================================

CARS ADDRESSED:

K-2026: High rewrites and read ECC's.

- Clear flag which allows abort to complete and return status. 

K-2095: FSC 26 on a write filemark after LEOT. FSC 26 on Locate to
filemark after LEOT then Write.
 
- Fixed bug in block type checking routine so it ignores the past
LEOT flag.  

C-155: No status returned on a load command issued following a
Space command - drive not  responding the the unload button
either.

- Added trap for infinite loop. Loop destroys information needed to
catch the bug. 

CODE ENHANCEMENTS (NO CARS ADDRESSED):

- Fix to prevent Space manager from disconnecting when it is
working with another manager. This bug was introduced on the
28th with the always disconnect before buffer search fix. 

- Changed code added on 5-22 to let IPORT interrrupts loose only if
record is compressed. This  will prevent overruns when in
compressed mode but data are not compressable.

05/28/92    8CC-043S  CC01043S/KS020571  CC01043T/KS020570
================================= 

CARS ADDRESSED: 

K-2089: FSC AC on a Test Unit Ready.

- For the Search File Reverse command, allow a command complete
primary status of 0x52 (Motion,EOT,Cartridge In) in case we begin
the search at EOT. 

K-2091: FSC 33 mispositioning error.

- Fix bug with block space back to Physical beginning of tape for
8500 drives when in file 0.  

C-175: No status sent to Host on Verify command (SCTAPE).

- Moved busif so that it would fit in compression code because of
fix for BENC feature when BENC is doing verify. 


CODE ENHANCEMENTS (NO CARS ADDRESSED):

- Took out changes to SENDTRIG, REPLYTRIG, REPLYSTAT so that the
sender id must be present in SENDERSLOT.

- If SAME parameter in SENDTRIG, makes same length expansion in all
banks.

- Changed macros using SENDERSLOT to not load the slot when sending
from a module with SENDERSLOT set to 0. This allows shoe to
compile to the same size for both banks (required for hang
code).

- Added new count for number of times LBOT read

- Always disconnect before searching the buffer. Some servers have
a problem with the max time we can spend searching the buffer. 

- Changed maximum compression synchronous negotiation speed from
5Mhz to 3.33Mhz to fix possible IPORT problem. This can easily
be reversed if need be.

- Changed SENDERSLOT back to INT_START (not doing this distorted
the trace).

- Changed all occurances of SENDTRIG to have parm SAME. This makes
the macro the same length for all banks.

- Add new count for number of times LBOT read. 

- Fix 8200 Mode Underruns - Caused by previous fix.   


05/27/92    8CC-043R   CC01043R/KS020561
===================================

CARS ADDRESSED:

K-2003: Read hang during positioning test.

- Modified code which has added on 5-12-92 to fix LOCATE problem in
order to save SPACE and time.

K-2025: Customer unique driver expects the Unit Attention for tape
loaded to come before the Busy status'. 8200 gives Unit
Attention and then Busy until it comes ready.   

- Added Eeprom option (with code modifications). The code can now
be configured to report C1H Unit Attention before reporting Busy.

K-2042: Hang on Write filemark. 

- Change iport code (8500 only) so the block complete interrupt
handler only sets the BEN transfer enable bit when necessary.
Unconditionally setting it can cause problems for BUSIF code. 
   

K-2066: Write hang.
              
C-2020: After a Write operation which fails with SK=03/FSC 9E, a
Request Sense and TUR command is issued.
     
- Changed reserve/release to work even if drive is broken.


CODE ENHANCEMENTS (NO CARS ADDRESSED):

- Added new entry point for ejecting tape. This entry point was
forgotten when Compression was first implemented. The missing entry
point caused a hang if the button was pushed when a command was
in progress. 

- Added slow motion read to compression code.

- Cleared the HOLEMODE bit when the fill manager is complete; the
switch from Read to Write uses BID search which checks this
value to determine splice location to search for. This        
problem was causing FSC 0x95 errors. 

- Watchdog Timeout due to excessive EOS (End of Stripe) VRBCs due
to Uncorrectable on last block of stripe pushing the WOQ past
the EOS point before the EOS Inturrupt. Fix skips RBC if
Uncorrectable Interrupt occurs when WOQ readback pointer is at
block 7 on stripe 1 or block F on stripe 2.

- Changed the MC_TRACK command for Compression, and 8500 drives. If
we are in 8200 mode, it behaves the same as 8500 mode now.

CUSTOMER UNIQUE ENHANCEMENTS:

- If bits 0 and 1 of CF_BITS6 are set, there will be a test 100 of
send diagnostics to fake a selftest if a tape is in the
drive. If there is no tape, operation is normal. The response from 
receive diags will be the same regardless of the test occuring.



05/26/92    8CC-043Q   CC01043Q/KS020551
===================================                

CARS ADDRESSED:

K-2664: Write hang.- Modified fix that was added on March 5.  

C-1094:- Fix to abort processing.  

CODE ENHANCEMENTS (NO CARS ADDRESSED):

- Changed code to perform the CLEAN ATM operation after F_Customer
Unique is done. We need to do this in 8200C mode to ensure that
the transfer is stopped before we try to track (because we need
to put the Formatter in 8200 mode).     

- Fix for 8200 mode block space back bug. Bug was only in
Compression code, where a SCHEDULE macro was used on a normal entry
point instead of a mailbox. 

- Changed counter used for request sense data extension. 

- Extended the timeouts for Compression and 8500 for servo powerup.

- Added Space manager scheduling address to fix an 8200 mode Back
Space Block bug on Compression machines. 

- Added code to fix a problem when starting a Read at the address
3FCH of the 3RD logical block. This is a BENC bug which was
fixed for LOCATE. It could also happen for read at higher
transfer speeds. The IPORT interrupts now are not disabled when in
8500 mode. This  will always let IPORT packet registers be
loaded before the prvious one finishes. This will prevent the 3RD
logical at 3FCH from happening during a Read.

- Added new compile flag around a LOGIT macro call that could not
compile because the routine LOGVALUE is not compiled when
EXT_ADR_SPACE is off. 

- Start blinking the amber LED before the UNLOAD on a hardware
error so in case the unload fails, the LED will still blink.  


CUSTOMER UNIQUE ENHANCEMENTS:

- Added trap for infinite loop from a car.  


05/22/92    8CC-043P   CC01043P/KS020551
=================================== 

CARS ADDRESSED:

K-2014:- Fix so a backward space will return hit PBOT even if the
tape is blank.  


CODE ENHANCEMENTS (NO CARS ADDRESSED):

- Modifications to support Compression code.

- Defined LOG_SENSE control bit for use in inline counter
incrementing routine.  

- Changed code to support Compression. The record size is bigger
(54E28h) and a bit is set in the control byte (ie, what to
load) to indicate Compression.

- Fixed a problem where setting the compression LED was disabling
the Formatter - Servo couldn't detect the tape.   

- Added routine for Compression code to read a byte out of any
bank.

- Temporary fix added to force data into bank 0 before doing a code
load for Compression code. 

- Put read bytes count back into 8500 code because it is used for
extend sense command. 

- Removed slow motion code from track capture. 

- Added log sense changes for new control byte and thresholding.

- Modified search algorithms that were stopping on equivalence for
PID, BID, or LID. 

- Fix check in pack loaded interrupt handler for buffer empty.  


05/21/92 85C-043N  KC01043N/KS020550
=====================================

CARS ADDRESSED:

C-0083: Hang on Write (IPORT Xfr stopped - Formatter 8200 bit set.)

- Remove setting Formatter in 8200 Mode if 'Single_Az' in Subr
'DEFUP_RDMD'. 

C-0086 and C-0173:  Write Hangs- Fix for 8200C mode problem at
LEOT. Now all available blocks are released before flush is
initiated.

C-0171: The logical Write manager does not terminate a BUSIF
transfer when the physical Write shuts down, causing a
hang in BUSIF.  

- Added new state (S-state 13h) to indicate we were requested to
disconnect when there was no disconnect privledge. This allows
drive to recover from a shutdown error when a data transfer is
inactive and we are not disconnected.  

C-2002: Hang on Read. Tape written in Write Dammit mode. Read
failed (FSC 08). Issued another Read, returned check condition
without any data transfer, issued another read then hang. 

- Added code to fix reading of "special" blocks.


C-2013: Tape written in compressed density (8C). Shows 8C after
forward space. Host issued Mode Select 8C, following Mode
Sense shows density 15.                        

- Copy the write control to the default when we reset. Fixed by not
reporting the default write density ever. Always report the
current read or write density.


CODE ENHANCEMENTS (NO CARS ADDRESSED):

- Removed SYS6EXT hardware type since it no longer exists. 

- Changed bankswitch routine address declaration so the correct
addesses are given for all machine types. 

- Rewrote segment positioning and length declarations for clarity
and added Compression declartions. 

- Added macros for mail (and other) entry points.

- Modified TIMEOUT macro for setting interrupt bank number.

- Modification so that PPOBIT2 is now the high bit of the bank so
we can select.  

- Added masks for bankswitching. 

- Removed entry point and link extern and public declarations which
are now made at the entry point in the manager file. 

- Changed the segment names to conform to the new segment naming
convention needed for 4 code bank implementation. 

- Changed entry point names. Now use macros on entry point names so
extern and public declarations are made automatically for
Compression. 

- Put the Formatter into 8200 mode for 8200C codeload and headsync
tapes so that track 2 is not FIFO'ed - this lets the Servo track
since the Block Ready Signal is now real time. 

- Added argument to TIMEOUT macro calls to automate assembly for
any bank. 

- Added a label XW_WRITE_BYPASS so the command handler can jump
directly to the write manager and avoid the scheduling overhead.
This is done to decrease the write access time. The    new label is
needed because the manager entry point, that was used by the
command handler previously, has different names depending upon
how the code is assembled and the new label avoids that problem.


- Return DCE based on tape if the READDEN option is set and we did
a read after a possible mode select. This is used to allow echo
of both the density and DCE. Now, DCE operates like density with
this option.

- Fixed non-LBOT check of DCE setting to conform with both the read
density option (ie, must be same as tape status on read) or work
the old way where DCE is based on the write density.

- Added V_KM_MNGR for expanded KM functions. 

- Redid public mail entries (with calls to banksw) to use macros
which automatically allow movement out of bank0.  

- Timer interrupts now use a byte for storing bank of interupt
routine. The old bank is stored on the stack.

- Scheduler changed so that triggers, etc where sender is
identified by high byte of calling address is changed. For
non-bank0, macro will put the high byte of the mail entry segment
(as in BUSIF for BUSIF_MAIN code) when do call. This gets rid of
code which is dependent on locations of modules (and speeds it
up too).

- Added new command for writing logical beginning of partition,
MC_WLBOP.

- Changed the primary status from 0x42 to 0x4A to include BOT for
the partition measurement command.   

- Added code to handle host initiated write aborts which were not
working due to BENC zero-fill problem.  

- Modified Mid Tape Wakeup so it will act like a Locate command and
not hit filemarks. 

- Fixed code error in the read pack loaded interrupt handler.

CUSTOMER UNIQUE CODE ENHANCEMENTS:

- Added _READDEN and _CLRREQSEN to CF_BITS13. Customer unique
requirements.

- Rewrote density selector for mode select. This was done to allow
the option of comparing the given density to the tape density,
not the write density, when not at LBOT.  

- Customer requests 0Dh, not D0h for differential card in the
inquiry data.  

- Added code to optionally clear the request sense data when
request sense is executed (without error).  

05/15/92  8CC-043M  CC01043M/KS020511
================================

CODE ENHANCEMENTS (NO CARS ADDRESSED):

- Added code to prevent disabling Deformatter before enabling it
for early EOS or RBCs.

- Fix bug in Load Trace.


05/14/92 85C-043K  KC01043K/KS020530 
         8CC-043L  CC01043L/KS020511
=====================================

CARS ADDRESSED:

C-164: FSC 8C on a Read in 8200C mode.  

- Read media problem executed an illegal thread in the code.
Illegal thread was fixed.


CODE ENHANCEMENTS (NO CARS ADDRESSED):

- Added flag to detemine if anything has been written when
switching back to read mode. - Development for setmarks.

- Added code to separate hardware failure write ABORT form Host
sending Abort message to  Abort Write operation.

- Added code to fix problem with Locate when at 3rd block and less
than two byte are left of the 3rd record.


CUSTOMER UNQIUE ENHANCEMENTS:

- Changed mode sense to allow an EEPROM option to only return pages
1, 2, F, 10, 20, 21, 22  when ask for all pages. All other
operations of mode sense and mode select are SCSI-2         
standard. It is now possible to access pages A and 11 directly.
This is to conform with the customer unqiue Engineering
Specification.  


05/12/92  8CC-043J CC01043J/KS020511
===================================

CODE ENHANCEMENTS (NO CARS ADDRESSED):

- Added flags for writing LBOP.

- Change processing so as to not reset the enable transfer bit if
it is already set.  This situation can occur if busif processing
finishes before iport gets started.  


05/11/92  8CC-043H  CC01043H/KS020511
====================================


CARS ADDRESSED:

C-167: Write hang - Aborted Write command returns wrong FSC on
subsequent request sense, and no status is returned on the
subsequent load command.

- Fixed abort so that we turn off flag which indicates DMA
transfer. Before, we entered data phase after abort of write
(sometimes). 

C-169: FSC 8C on Erase command.

- Fixed bug introduced inadvertantly in code optimization. 

C-170: FSC 8C running motion in 8500 mode Space filemark command.

- Changed location of sync variables such that thhey are not
cleared at search field initiation, but only at LBOT

C-2006: Missing reporting of the Save Data Pointers bit in Page 20.

- Added RSDP to mode sense of page 20h per customer unique request.
The mode select was there but not the mode sense.  


CODE ENHANCEMENTS (NO CARS ADDRESSED):

- Changed code so that we can abort out of a transfer from the
drive properly. 

- Added PID search for all versions of code

- Modified searches for changing partitions and LBOP search during
formatting, and PID search, and a little bit more. 

- Fix defect in Write Setmark algorithm. Increment Set Number from
SETMARK before storing into CURSN for Search Fields. 


05/08/92  8CC-043G CC01043G/KS020511
====================================

CARS ADDRESSED:

C-165: No status returned on Write command. Data transfer had
completed while trying to stop the transfer in 8200C mode,
but no status was returned to Host.

- Corrected code to send status when the transfer is complete.

C-166: FSC 8C on a Write command.

- Modified code so that 8200C stop transfer occurs before Write can
occur.

C-1095: After SCSI bus reset, TUR issued and expect a check
condition with a Unit Attention. Another TUR is issued and
expects a good status but a check condition is returned.    

- Get saved copy of tape handling flag. This byte is checked and
updated every time the primary status is changed. The byte is
preserved through reset.

CODE ENHANCEMENTS (NO CARS ADDRESSED):

- Modified code to report Write protect only when a cartridge is in
the drive (or soft write protect for a customer feature).
Before, the drive would return write protect after eject.

- Fixed reporting of RTF/WTF so it matches density returned in mode
sense when the density is the read tape format. Before, would
not match under some circumstances, such as fix 3.

- Fixed reporting of density of tape when tape is of unknown format
or blank. Before, we could get 15h density on 8200c.  Now, we
report the write density whenever there is no tape or blank tape
or unknown format tape.

- Copy default compression mode when eject tape. Before, we only
copied the basic density type. Now, all modes are retained.  

- After servo finishes its selftest, check if the drive is a
8200c. If so, don't turn off the amber LED if the drive
needs cleaned. 

- Fixed ILI problem detected during SCTape testing.

- Fixed Abort processing while in Write suspend mode.

- Development for partitions.


05/07/92  CC01043F/KS020511
============================================

CARS ADDRESSED:

C-1087: A rewind after an aborted Write posts a check condition -
FSC 9B. Status is not cleared after Abort.

- Added code to set the Logical ID, Block ID and Available Blocks
to the status prior to the aborted record.


CODE ENHANCEMENTS (NO CARS ADDRESSED):

- Development for setmarks and partitions.

- Fixed a bug in the partition measurement command. Expect a
primary status change of 0x42 instead of 0xC2.  

- Fixed true density so we default correctly on 8200c.

- Changed request sense so machine sense never returned if the FSC
is in the range of 0C0h..0F9h (ie, SCSI cmd errors).This is for
multi-host.

- Fixed Abort processing during Write to allow interrupts to
continue when Abort command is received. 

- Fixed problem with decrementing counter to FFFFH during ILI when
the record on tape is longer than the requested record.


CUSTOMER UNIQUE ENHANCEMENT:

- Changed special byte of inquiry to give value 0D0h with the
differential card.


05/06/92  CC01043E/KS020511
============================================

CARS ADDRESSED:

K-1550: Drive failure during component qualification test.

- Fixed problem in reporting Power On Self Test failure. We only
have 2 possible failures. They are ram and servo. We will return
FSC A4 for ram and FSC AD for servo. Before, we did not report
correctly.  

C-0067: Append - Failed on a command Read FSC BC

- Fix for positioning after read abort.  

C-0161: Servo error encountered on Read command results in a hang.
The error condition is not  reported to the Host. 

- Fix causes buffer positioning code to resync pointers which can
be left in an improper state by the abort.  

CODE ENHANCEMENTS (NO CARS ADDRESSED):

- Development for setmarks and partitions. 

- Set flags if an erase is issued from LBOT. This prevents trying
to read a tape that has just been erased.

- Compression drives require the character - or \ in the
codeload header. Previously (ie,last 2 months), no particular
character was required for these drives. As a result, only very   
ancient code will not be able to take the new codeload tapes and
this change is temporary until this version of code has propagated
and allows us to check for \. In summary, this is in preparation
for making sure 8500 tapes go to 8500 only.

- Modified handling of codeload fail information storage.

- Changed code to make 8200c dump servo from 2000h. This also
changes the length of the tape file for these devices. It is now
length 34628h.
==> WARNING <==.  8200C REQUIRE MANUAL LOADING OF THIS            
    CODE VIA SCSI OR MONITOR BEFORE THE CODELOAD CAN WORK.

- Fix to reposition after read abort (compression drives only).  

- Fixes for 8200C stop transfer while positioning.  

- Fix to abort code. No longer send a message to terminate the
transfer if disconnected because of buffer full.  

- Made a RSmk default to 1 for an EEPROM with 0 in the position.
This is done so that the default enables reporting of setmarks.

- Added code to report overflow of log counter when RLEC bit set.

- Fixed bug with log parameter overflow marking. 

- Clear update bit on log counters when RLEC goes from 0 to 1 on
mode sel.

- Added code to write abort processing to handle abort command
while in suspended (buffer full) mode.  

05/01/92 CC01043C/KS020511 
         KC01043D/KS020520 =====================================

CARS ADDRESSED:

K-2055: Drive reports NOT READY with tape loaded and green LED on.

- Force broken state on servo timeout so when servo dies on
power-up, we know about it and tell the host.  


CODE ENHANCEMENTS (NO CARS ADDRESSED):

- Added flag in external memory for logical write 8200c processing
of buffer full. 

- Added flags to resolve BEN conflict. The flags are used during
buffer full processing and when the STOP TRANSFER and RESUME
TRANSFER messages are received from the logical write manager.

- Development for Mid Tape Wakeup.

- Removed test code for missed ATM problem. 

- Fixes for 8200C stop transfer while positioning, and restart of
transfer after suspension for buffer full. 

- Fix to partitioned LBOT.

- Corrected overwrite of Accumulator during erased gap processing. 

- Corrected setmark search command to retrieve desired setmark.

- Corrected SPACE verification of search field partition which was
overwritting on chip memory.
 
- Added LBOT processing for partitions.

- Added verification searchs don't change partition.

- Modifications to facilitate assembling of code. 

- If we get a "needs cleaning" interrupt from servo and it's a
standard 8200C drive, flash the amber LED.  

- Modification for 8200c mode to detect if buffer is full (need to
suspend write) while writing the last block of a write command.


04/23/92  85C-043B  KC01043B/KS020490
==================================

CARS ADDRESSED:

C-156: Motion test - 8200 mode - read command hangs following space
command due to infinite loop.   

- Changed code to insure that all types of filemarks are detectable
at all times and that filemark detected status is properly
returned to the manager.   


CODE ENHANCEMENTS (NO CARS ADDRESSED):

- Added a new flag for Fatal Error Codes.

- Added bit definition for set number. 

- Deleted some unused mail messages.

- Added Set_Id offset definition in BRT.

- Changed Mid Tape Wakeup fault symptom code definitions. 

- Numerous fixes for 8200C BEN stop transfer problems. 

- Allow length of 32768H for read/write buffer.  

- Fixed page A of mode sense to return length of 6 (was 8).  

- Enhanced log sense/select implementation. All counters returned
by log sense will return 0 until the updates for the counters
are changed. 

- Added special request sense to return number of physical bytes
read. This is cleared on reset, by log select, and by clear
counters bit of request sense.

- Added page A to mode select/sense of compression drives. This is
used to enable the log sense comparisons. This will affect
anyone who uses page 3F (all pages) for mode sense. 

- Fixed problem in Write Setmark algorithm.

- Enhanced LBOT processing for tracking errors.

- Fixed a problem so now if prevent media removal is set and an
UNLOAD command is issued, or a Servo Error occurs which would
normally cause reject, the tape will not eject.  

- Added code to force selection of compression densities via page
F, not by the block descriptor (current method).  


CUSTOMER UNIQUE ENHANCEMENTS:

- Customer unique amber LED handling for a servo hardware error.  


04/17/92  KC010439/KS020471 ==================================
          CC01043A/KS020472

CARS ADDRESSED:

K-1535: Drive failed on a command Space. 

- Modified processing of window of reverse ATM search and timing
out on hitting it during a block space operation. 

K-2018: When a command is not queued, the drive will return status
back on checks.

- Changed the resulting FSC, ASC, ASCQ set to report not ready but
becomming ready if the drive will be ready. This is done when a
command is not queued either because there is already a queued
cmd, action cmd, or queueing is not allowed and should report not
ready.  

K-2024: The load command doesn't clear a check condition, but
unload, rewind, etc. will.

- Clear flag for media error when doing a load command, assuming
there are no errors in the CDB. This will clear errors such as
9E and allow the drive to run again. 

C-153: SCSI bus hang running Write/Read test with new Ben.

- Corrected check of number of blocks in buffer. The check is made
in the 8500 read interrupt handler (pack-loaded).  

C-1075: 8500 doesn't report a unit attention on load in the same
fashion as an 8200.

- Modified routine to check for tape available. Now, we return a
status on whether or not the SCSI command given requires a tape
for operation.  

C-1076: Synchronous Negotiation problem.

- Changed the code to allow message reject msg (07h) after target
initiated synchronous negotiations. If this occurs, we
will go back to asynchronous mode.  


CODE ENHANCEMENTS (NO CARS ADDRESSED):

- Added messages to IPORT to stop and resume transfer of data. Also
added status response to stop transfer message. 

- Added Mid Tape Wakeup support.

- Added temporary trace table for 8200 missed ATM problem. 

- Added code for the 8200C position to write tracking problem. 

- Added flag to indicate that a stop transfer message was received
and drive is waiting to abort data flow.

- Added support for log select.  

- Add handling for Stop/Restart transfer message flow for Single
Azimuth Position for Write Tracking. 

- Added clean up after LSI tests that corrupted the interrupt
control registers.    

- Added jump table entry for monitor so it can make a tape with
only EEPROM which is  generated by the monitor.  

- Modified the criteria for clearing the flag for Space/Locate
operations on tapes containing setmarks. 

- Changed flags to defer sending STATUS and setting Formatter to
8200 mode (for SA Track-ing). Instead, send Trigger to cause
transfer to stop. 

- Changed physical write command parser to wait to change Formatter
to 8200 mode.  

- Added changes to fix SCSI hang and prevent conflict between IPORT
and DPORT for access to IPORT registers. 

- Development for setmarks. 

CUSTOMER UNIQUE ENHANCEMENTS:

- Fixed problem with asserting ATN during information transfer to
host in synchronous mode. This caused the problem with a customer
unique mode sense. Now, raising ATN will not cause the drive to
hang.


04/13/92  8CC-0438  CC010438/KS020422 ============================

CODE ENHANCEMENTS (NO CARS ADDRESSED):

- Added definitions for the future implementation of log
sense/select with full implementation of the commands. 

- Added support for the sense buffer command (also for single
azimuth).

- Mid tape wakeup development.

- Setmark and partition development.

- Fixed overflow condition in a byte counter.


CUSTOMER CODE ENHANCEMENTS:

- Changed code so that when a customer unique bit is set in the
customer unique mode select, density code 90H is illegal in mode
select and DCC is ignored if the current write mode is 14h or 15h
(ie, non-compressed).  

- Changed code so that if customer unique mode select is choosen
and the eeprom flag ALLOW_RAW is off, the DDE bit is ignored and
always returns 1.  


04/09/92  85C-0437  KC010437/KS020430
=====================================

CODE ENHANCEMENTS (NO CARS ADDRESSED):

- Added a variable for Mid Tape Wakeup to the image area of the
EEPROM to allow accurate reporting when the EEPROMs lifetime has
been used up. 

- Added Partition development.  

- Corrected FSC 8C caused by an incorrect indexing during ECC count
correction processing. 

- Mid Tape Wakeup development.


04/08/92  85C-0435  KC010435/KS020410
                    CC010436/KS020422
====================================          
CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Development for Setmarks.

- Added code to detect and move us over valid erase gaps and retry
on head clogs.   

- Changed holemode mailing so it will not send the trigger after
the status.

- Fixed bug in writing Set Number to Buffer. Caused 8C on WFM.

- Fixed bug in parsing block types when filling the WOQ. Any
compression write got 8C.

- Added code to fix a problem with missing data packets (BRTS)
during a Read operation. This resulted in CRC failures for the
Compression units. And ILI, Read hangs for 8500 and 8200.


04/07/92    85C-0434   KC010434/KS020410
================================          
CARS ADDRESSED:

K-1526: Failed on command Space (blk space).

- While trying to track, declare a servo software error if we don't
get motion, tracking, cartridge in or motion, tracking, eot,
cartridge in. Error is not corrected, it is only reported sooner. 

K-1528: Failed on command Write. 

- With as FSC 8C, the timer is in use by MOTION when DPORTW
attempts to time LOAD Interrupts. This problem is caused by a
deficiency in the Bad Splice handling of servo off track errors.


C-13: Mode Select data compression enable (DDE) bit off a variable
read resulted in a hung bus.

- Changed Test Unit Ready to report FSC C9 instead of FSC C4 when
ejecting due to a button press.  


CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Changed flag so that setmarks are always part of compression
code.

- Fixed assembly errors.

- Modified code so that if we are doing an UNLOAD with single
azimuth and if the No Auto Load bit is set, we check the LOADED
bit by doing a show status byte 03. 


04/06/92 85C-0433 KC010433/KS020400
========================================

CARS ADDRESSED:

C-139: FSC 99 on a Write test 8516. Writing in 8200 mode size=2561
1BLK/CDB 1000 CDBS.              
- Fixed for no disconnect mode in 8200 mode on compression drives
which caused the drive to think the buffer was full when it was
not. When the drive attempted to flush the empty buffer it caused
a FSC 99 error.  


CODE ENHANCEMENTS: 

- Added more development for Setmarks and Partitions.

- Added retryable error codes.

- Added new bit flag indicating motion busy while performing a
backhitch.

- Added variable for storing failure point of mode select (the byte
number) so we can return that instead of the FSC when an error
occurs.

- Added logic to stop additional motion commands from being issued
when read recovery recovers blocks close to EOD. This was causing
an FSC 0x8C.

- Fixed code so that if EEPROM has prevent on, any allow by a host
will clear it.

- Fixed problem with FSC EA. The ASC was not returned (was 0). Now,
it returns the correct ASC. This occurs when using compression
mode while in wrong density.

- Added a 10 sec. extension for single azimuth. It takes Single
Azimuth longer to Post.

- Added more Mid Tape Wakup development.

- For Single azimuth drives, we increased the timeout to 45 seconds
on an UNLOAD due to an error. 


03/31/92    8CC-0432   CC010432/KS020342
=============================== 

C-120: FSC 95 is reported incorrectly after a new tape is loaded.

- Clear the soft broken flag (ie, media error flag) when a tape is
loaded. This will make sure that deferred errors such as 95h are
cleared on a new tape. The 95h error will report until the new   
media is present. This is done to preserve the error but to make
sure it is cleared at the new load time.  



CODE ENHANCEMENTS (NO CARS ADDRESSED):

- Add restriction to IPORT interrupts for read mode. The
restriction was removed due to the SCSI hang problem with
BENC-1.

- Changed code to check for overflow of M_PARAMETER. Now it remains
as 0xFF.  

- Added code to fix problem with Single Azimuth Mode when it
switches to 8200 mode. This switch could result in zero filling
some Physical Blocks, and not returning an FSC-99.

CUSTOMER UNIQUE ENHANCEMENTS:

C-1067: Drive returns check condition (Not_Ready) status instead of
good status during a load operation when polled with test unit
ready.  

- Problem was detected in a customer unique version for Test Unit
Ready.  

- Changed inquiry to put 'A' or 'R' as last byte of revision level.
The rest of the revision is shifted over 1 character.

03/31/92    85C-0431   KC010431/KS020370
==================================    
CARS ADDRESSED:

K-1502: Issued mode select to set No Disconnect bit.

- Added code to check for range of thresholds. 


CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Development for setmarks and partitions. 

- Fixed bug in bad splice prevention.


03/27/92    85C-0430   KC010430/KS020360
===================================  
CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Fixed a problem with tracking retry.

- Mid tape wakeup development.


03/26/92   85C-042Z   KC01042Z/KS020340
====================================

CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Added setmark definition.

- Remove test code for read recover.

- Mid Tape Wakeup development.

- Removed timer being set when a permanent error is declared,
causing motion to "hang" due to the timer in use.

- Add track with averaging as first read recovery.


03/25/92   85C-042Y  KC01042Y/KS030320
=====================================

CARS ADDRESSED:

K-2618: Wrote large logical blocks 240K & residual count is still
too large based on 8500 buffer size.

- Modified residual value to reflect number of logical blocks
rather than physical blocks on a fatal write error.

C-1054: Write hang, disconnect no reconnect. 

- Added compression code to get BEN information when disconnecting.
This is used to trap errors where write freezes.  

K-2682: Write hang, write hang reselection.

- Added code to ACK interrupt from SCSI chip when write mode and
BEN is really accessible and not zero filling.  

K-2602, K-2628, K-2656, K-2698: FSC 15

- Modified block timeout value such that it no longer varies in
value depending upon tracking and ampsense. The previous
algorithm was suspected of positioning the tape to far into the   
ATM on short FMs.


CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Development for Setmarks and Partitions.

- Modifications for new message traffic supporting of Go Slow Servo
for reporting  timeout conditions.

- Modification to deal with the Zero Buffer flag's move to external
memory for setmark and partition implementation. 

- Mid tape wakeup development.

- Fix for bad splices. 

- Added counter for write retries. 

- Changed position for Write failure backhitch from 50h to 12h
stripes.  

- Made a minor improvement to scheduling to save a cycle or 2. 

- Added support for the new read recovery mechanism.

- Changed command to handle an 8500 drive in 8200 mode so that it
behaves the same as 8500 mode now.

- Modification to handle a new primary status change of 0xFF with
extended 40h - this tells us that the tape got stuck while going in
slow mode.

- Added new commands for SETMARK handling to command jump table.All
are invalid at this point. 

- Added new macro code at the bottom of the source code that
computes the size of IPORT. The new code indicates whether the
size is greater than the allotment (and by how much) or within   
the allotment. 


03/24/92  8CC-042X  CC01042X/KS020311
=====================================

- Fix for FSC(95) problems when trying to Append to EOD.

- Fix to abort handling of read for compression drives.  

- Added code to fix reporting of incorrect residual after a
filemark or EOD on very special cases.

- After an ILI, the read fix of several blocks did not work. The
number of records sent to the Host were one less than the number
requested.


03/23/92  85C-042W  KC01042W/KS020320 
==================================

CARS ADDRESSED:
 
K-1512: Mail decode problem. 

- There was a timing window in backspace block space code in 8200
mode where a timed backspace block movement completed at the same
time an ATM was detected. 


CODE ENHANCEMENTS (NO CARS ADDRESSED):

- Fixed FSC(95) problems when trying to Append to EOD. 

- Fixed Abort handling of read for compression drives.  

- Added code to fix reporting of incorrect residue after a filemark
or EOD on very special cases.

- Add code to correct handling of ILI after a read. The number of
blocks sent to the host were less than the number requested.


03/18/92  85C-042U  KC01042U/KS020272 
          8CC-042V  CC01042V/KS020261
==================================

CARS ADDRESSED:

K-2692: Hang on Write (8200 mode)

- Corrected a Mail message decode bug in the switch Read to Write
Manager.

CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Fix to prevent a bit from causing a bad LBOT to be written when
a non-compression drive overwrites a compression tape.

- Fix for compression to test if we are really on the EOT side of
a filemark when splicing. 

- Added code to fix Read hangs. 

- Added code to support physical block checksum for more data
integrity check. 

- Removed some looping to speed up Write functionality.

- Added code to fix ILI problem with new BENC-2 which caused a CRC
error when the record on tape was longer than the one requested
by the Host.


03/18/92  8CC-042S  CC01042S/KS020261
=======================================
          85C-042T  KC01042T/KS020271

CODE ENHANCEMENTS:

- Removed all of special code for 8200 mode for old BENC-2 and add
code to support new BENC-3. 

- Add code to fix a problem with special block handling.

- Add code to fix the hang problem due to sending 0 status. The
8200 mode of operation from this version on will not support
8200 mode for old BENC-2. It will support all modes for new BENC-3.


03/16/92  85C-042R  KC01042R/KS020261
=====================================

CARS ADDRESSED:

K-2684, K-2685 & K-1509: Drive failed on FSC 8C on a write
filemark. 

- 8C caused by failure to store error code correctly when bad block
type was detected in RBC.


CODE ENHANCEMENTS (NO CARS ADDRESSED):

- Added a command for instructing the space module to perform a
space operation for mid tape wakeup.

- Modified code to prevent reading invalid headsync and codeload
tapes.   

- Added code to set the Servo configuration upon completion of a
LOAD or REWIND.

- Modified backhitch handling - single azimuth Servo will do the
long backhitch to perform write adaption.

- Modified handling when doing a Read 1 LBOT.

- Fixed yet another abort bug. Link was corrupted causing a hang
when the abort done was sent. 

- Correct read LBOT logic pertaining to NON8500 bit used by single
azimuth found in LBOT header.

- Mid tape wakeup sleep/wakeup command development.

- Set the tracking offset to 0xFFFFC3 for single azimuth in
8200/8200C modes.


03/14/92  85C-042Q  KC01042Q/KS020271
=====================================

Servo Change - Corrected a counter to track reel motion failure.


03/12/92  8CC-042P  CC01042P/KS020261
======================================

CODE ENHANCEMENTS (NO CARS ADDRESSED):

- Mid tape wakeup development.


03/12/92  85C-042N  KC01042N/KS020270
=====================================

CARS ADDRESSED:

C-1036: SCSI-2 compliance issue.

- Changed code to allow variable read/write to occur if the logical
block size is >0. This overrides the fixed size and causes a
variable operation.

C-1041: Hang on Read.

- Added code to fix a problem with sending multiple statuses in
8200 mode.

CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Development for setmarks and partitions.  


03/11/92  8CC-042M  CC01042M/KS020270
====================================

CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Mid tape wakeup development.

- Fixed an Abort problem.  


03/11/92  8CC-042L  CC01042L/KS020261
=====================================

CARS ADDRESSED:

K-2640: Request Sense bytes 26 and 27 are not cleared when the
drive has a mode switch from a Read to a Write and vice versa.

- Added code to clear the tracking retry counter, read retry
counter, and write retry counter on a switch from read to write
or from write to read.  

K-2660 : FSC 8C on a backspace filemark

- Change FSC 0x8C reported on reading BAD EOD to FSC 0x16.

K- 2674:FSC 8C on a back space block

- Clear "don't corrupt BR" bit when command aborted.

K-2675, 2679: Software hang on a Read

- Clear byte containing bit flags on an abort.

C-112, 114: FSC 8C on a Space

- Set "ALIGNED" flag when read enters a holemode retry to prevent
fast alignment during hole-mode which corrupts the BRT. 

C-1024: Write hang in variable 8200 mode

- Prevented the transfer done from sending status. Now the manager
will wait to send status. 

CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Fixed a problem with splicing for compression. 

- Development for setmarks and partitions.

- Fixed problem where mode sense length 4 gave error.

- Took out temporary code which defaulted EBD to off in compression
drives. 

- Took out error checking for page number for mode sense. 

- Changed mode sense to use different way of determining which
pages to send.  

- Added new page code (x11) for compression drives.  


03/06/92  85C-042J  KC01042J/KS020270
======================================

CODE ENHANCEMENTS (NO CARS ADDRESSED):

- Added flags for 8200 LBOT single azimuth processing.

- Increased timeout for tape load from 90 seconds to 3 minutes.

- Added code to sense and eject media (Hi-8 and ME).


03/05/92  85C-042G KC01042G/KS020270
====================================

CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Development for setmarks and partitions.

- Added flag for parity error ignore when dumping bytes in info
command data out phase (ie, when ignoring bytes of a mode
select).  

- Added support for 8200 mode space to eod. 

- Optimized pointer used in mode select data trace. Also, added end
marker (EE) after last byte transferred.  

- Fixed bug where parity error on byte after bad byte in mode
select data would cause problems.  
- Modified request sense calculation of read/write retry counter
for read. 

- Clear the parity error flag and parity ignore flags when start
new info command. Fix for parity error problem when the drive
gets a parity error on byte in mode select after an incorrect byte.


- Added new error code to the error tables.  


03/04/92  8CC-042F  CC01042F/KS020270
=====================================

CARS ADDRESSED:

K-2624: Drum motion failure

- Added a timeout of 11.5 seconds for the blank sense command.  

K-2638: Inquiry commands with non 0 LUNs in identify message
respond incorrectly

- Added flag into the control byte of the CDB to indicate that
there was a LUN error. This is used to tell inquiry to return
the correct byte value in byte 0. This fixes reporting of device
type on illegal LUN for the inquiry command.  

K-2664: Hang on Write 

- Fix where disconnect was sent before terminate data transfer had
completed. This occurs during LEOT handling after the release of
all data in buffer to physical write. Now the disconnect is   
delayed until the terminate data transfer is received. 

K-2585: FSC 36 on Space Block

- 0B Error on Read due to failure to overwrite old data. Add test
for nonmatching non-gap block types for all corrected RBC'd
blocks having matching PIDs. Matching means WOQ value = Header
value. Permanent Write Error (FSC 9B - F_LD_TER) will result from
mismatch. 

C-0111: SCSI Bus Hang

- Add code to reset all Write flags after switching to Write mode.

C-0113: FSC 8C 
        
- Add code to stop transfer after the 1st CRC error during Read. 


CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Deleted Fatal Error Codes.

- Added Fatal Error Code for Overwrite Error (1B). 

- Added a family of branch macros which can jump arbitrary
distances. These macros allow the specification of logic at a
higher level of abstraction, which improves readability. 

- Took out conditional assembly flags around code which clears
various read compression flags before LBOT read. This insures
the flags are cleared if an 8C tape was in an 8500 drive and   
then a 15 tape is inserted. 

- Added support for 8200 mode space to eod.

- Added a comment prefix system to show which flags are in effect
at that point in the file. This makes it a lot easier to tell
which code is in which bank or on which hardware. 

- Uncommented "removal" of setmark in search field validation in
preparation of set marks.

- Modified calculation and handling of read retry count return via
SCSI.

- LOG SENSE correct byte count in compressed mode.

- Removed verifiction of non-8500 bit in LBOT. Tape format
acceptablility and hardware set up were moved. 

- Installed trap to catch the WRITE ENABLE not set.

- Allow a change in primary status from 0x42 to 0x02 and 0x46 to
0x02. This is when we are searching to EOD and then we stop.  

- Added code to set the 25th bit BLK_ID to 0 when reseting BENC
IPORT.

02/28/92  8CC-042D CC01042D/KS020155
======================================

CARS ADDRESSED:

K-2662: Request Sense does not update sense byte 19 bits 0 & 1 as
stated in the User's Manual.  
- Modified code so that the TNP and LBOT in USB0 (byte 18 of
request sense) are always current (reflecting active state).


K-2664: Hang on Write

- Defined special Save Data Pointer modes with CF_BITS13 bits 2 and
3. Added feature to force save pointers on any data transfer or
to force save pointers when they terminate a transfer due    to
LEOT.

C-0028: SCSI bus hang on 8200 density Write

- Removed fix for C-0028. The correction to the write density
problem amplified the Write enable 4K boundary SCSI problem
(corrected in the next turn of BENC). 

C-0042: Unexpected timeout doing a fixed Verify command

- If an occurs ILI during a Read or/Verify with small logical
blocks and a buffer empty condition, the IPORT transfer
was disabled. For BENC to calculate the correct residual and    
complete the current record action, the transfer must be enabled.

C-1028: Unexpected status on Read operation

- Fix problem with incorrect LID in filemark block type after the
Write command was stopped due to the detection of LEOT.

CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Added new commands for spacing to EOD.

- Added variables for storing state of mode select. These are
needed for partitions since mode select must work differently to
support them.

- Added compression flags around PUBLIC/EXTERN for motion's POST
ALERT.

- Added code to ignore the Mode Select density and just do it in
8200C format if making a headsync or codeload tape in a 8200C.

- Added a path for mid tape wakeup when doing an autoload which
stops this manager before actually reloading the tape (since MTW
left the tape already loaded).


CUSTOMER UNIQUE ENHANCEMENTS:

- Only allow switching the compression LED from green to amber or
vice versa, if not customer unique.

- Added abort handling for low speed search.

- Added code to handle the drive needs cleaning interrupt from
servo on power up.  


02/25/92  8CC-042B  CC01042B/KS020155
====================================

CAR ADDRESSED:

C-1013, 1023: Hang on Write

- In certain cases, BENC is not idle but the BYTE-COUNT-0 interrupt
has occured. Add code to handle this case.

C-1019: Incorrect residual on read.

- Modified code which generates partial EEIMAGE to give 1Eh bytes
instead of 16h bytes. This copies all EEIMAGE data in the mode
select part up to but not including CF_BITS0. Before, copied
bytes 1C to 31h. NOTE: This Affects both compression and
non-compression drives (the non-compression drives get more mode
selectable data copied over than before).

C-1027: Read hang.

- Added code for problem with read pause in 8200 mode. This problem
resulted due to out of sequence loaded and pack loaded interrupts
occuring before transfer was active in the main read task.

- Also added code for a problem with not completing a write
command. 


CODE ENHANCEMENTS (NO CARS ADDRESSED):

- Repaired some FATAL ERROR HANDLER logic that caused a servo fatal
error to be reported    with the incorrect FSC (0xc0). This could
have caused reaching LEOT to be reported as a software hang. 

- Additional fixes for Test Unit Ready. When Queuing is set for
Busy mode, we return busy if the drive is working on a command
or ready and it is not idle. We cannot get Not Ready from Test
Unit Ready when Queuing is in Busy mode unless the drive is idle
and the tape is not loaded.

- Increase the backhitch distance by 5 tracks if a Compression deck
until the Servo tracking  Acquisition is improved (tracking timeout
also increased by 5 tracks).




02/14/92
KC010428/KS020220===============================================

Added more midtape wakeup code.

Fixed a compression ILI problem.

Fixed a problem introduced in the last version of code where we were always
backhitching 0x0a tracks on tracking retries.  (We should be backhitching 9
tracks initially and then 5 further each retry.  An added JBC_G instruction
was clobbering the ACC, so I saved and then restored the ACC.

CARS:

C-0022 FSC(x95) errors which occur during an 8200C append type operation. 
This fix will get us through the erase gap and retry the positioning operation
on a SA tape.

K-1020 HANG in SA when a BAD ATM detected Fixed problem for 8200C mode where
BADDTM message hung because of a test that checked if the drive was in 8500
mode.  The BADDTM message is not legal in 8500 mode but it is in 8200C which
has the 8500MODE flag on as well as the SINGLE_AZ flag. The test now checks
for SA 

02/1292
KC010427/KS020210===============================================

OPTIMIZED mainline code for LBOT retries and special in the BRT handling.

Added initial midtape wakeup support to SCSI

Added option to allow No Op (instead of error) of threshold data sent by
log sense command.  

When configured in EEPROM, will update TNP, LBOT for every request sense
command (these bits in USB0).  This makes sure they are live.

Added code to clear the _TRKPLL bit when getting on track and also when
updating the tracking retry counter.  Inadvertently, this bit was left on and
we declared M_NOT_TRACKPLL when it should have been M_NOT_TRACKING.

Fixed backzone measurement routine so it will handle SPECIAL BRTs.  This is a
problem when the only thing in the buffer is a SPECIAL because of a media
error.

Fixed problem sending message to wrong task for compression.

CARS:

K-1461,C-0008,C-0019,C-0023:  Enhanced recovery during reading of SA erased
gaps.  The enhancement is to force a reread attempt before declaring a media
error (FSC 0X16).

C-1017: Host Timeout (Compression) - Partial Fix Mode stuck in endless
POSITION FOR WRITE retry loop when OVERSHOOT was detected on first PID read
for the search. The fix re-includes this case in the retry count which, at
overflow, will cause a 95 error so the real cause of the mis-position will be
in the trace if the problem reoccurs.

02/11/92
KC010425/KS020210================================================

Added several mid tape wakeup inhancements. These improvements implement a
more descriptive interface between midtape wakeup and motion.

Added new motion error for not tracking due to the drum losing lock.

To support new configurations:
Added config bit to control starting in 8200 mode and later changing Added
config bit if TRUE, TND and LBOT in USB0 are updated even if the sense is saved
because the last command created a check condition.

Compression 
Fix for checking if the drive is compression. If so, we control the compression 
LED's color.  Also, clear color when switching to 8200 mode.

Changed customer unique LEDs to turn on amber LED when a bad codeload tape
is  inserted (I had turned it off).

Added SCSI support for Host notification  of unsupported media. Added FSC C5,
ASC 30, ASCQ 0.

Change of plan:  When tape is ejecting or idle, we cannot be busy. Therefore,
if we are not ready, we are not ready.  This solves problems associated with
NAL and PREVENT.  Fix superceeds previous Test Unit Ready changes.

Added code to return not ready instead of busy when PREVENT on (as well as
NAL [aka No AutoLoad]) when tape is not loading, ejecting and in the drive.

Added code to the TRACK command to check if we are not getting on track due
to the drum losing lock.

Changed the ASCQ of FSC 1C from 00 to 01. This indicates that it is the format
of the data on the tape, not the physical tape, that is the problem (ie, format
incompatible and not recognized by the drive).  This FSC occurs on reads of
8500C tapes on 8500 (for example).

Added FSC B0 (Sense Key 3, ASC 9, ASCQ 0).  Same actions as FSC AE but is used
to indicate a different kind of tracking error (Phase Lock Loop not tracking).

Allow a change in primary status from 0x42 (extended 0) to 0x42 (extended 1 or
2) in the primary status change table for losing drum lock when trying to track.

CARS:

K-1489 - 8C due to Watch Dog Timer while in WRITE ERROR processing.  Bypass
counting rewrites for Sense and Log Select when forcing them during WRITE
RECOVERY or WRITE ERROR SHUTDOWN.  This shortens the code path and also
results in a better reporting of rewrites.

K-2623 - Increment PLL_PID for the special case when the drum loses lock
while writing LBOT and PID is FFFFFFh.

C-1015 - I_release is called even when there was no previous write. Sense
there is nothing for IPORT to flush I_release never completed. Added check to
prevent code from hanging in compression mode.

02/06/92       CC010424/KS020154======================================
               ====

CARS ADDRESSED:

C-1012: FSC 99 - Write out queue fill error - buffer empty.

- Available block was not updated when flushing in 8200 mode.

CODE ENHANCEMENTS (NO CARS ADDRESSED):

- Add new flag to handle a timeout when trying to
  position prior to an 8200C CLEAN ATM operation.

01/31-02/05/92 CC01041Y/KS020150 - KC010420/KS020180 - CC010421/KS020153
               KC010422/KS020180 ==========================================

CARS ADDRESSED:

CARs #K1461, #C0008, #C0019, #C0023: Single Azimuth media errors.

- Added new DPORTR command and status for new read recovery during single 
  azimuth detection of FM and EOD.

CARs C-1008, 1005, 109: Read Media errors.

- Add code to assure sending one status at a time during CRC error
processing.

CAR K-2611: Write media error residual is incorrect.

- Fixed calculation of residual for fixed block write when fatal write error
  occurs. For fixed blocks, this calculation gives the number of blocks of
  data not written to the tape. Thus, in buffered mode, this number could
  be greater than the transfer length.  

CAR C-0021: Request Sense valid bit not set following ILI.   

- Set the valid bit on the illegal length residue for a variable length read.

CAR 1010: Read hang on 1 byte records.

- Add code to prevent sending two ILI statuses when reading a short record. 

CAR C-1011: Back space failed.

- Clear the compression flags when we switch to 8200 mode (read to write
switch).  


CODE ENHANCEMENTS (NO CARS ADDRESSED):

- Correct error caused by optimization of subroutine. Error was causing a
failure 
  to zero the reread counts. 

- Added flags to signal a return to EOT side of filemark splice code after 
  executing a subroutine to position for the splice. 

- Added bits for future feature of preventing code load tape operation.  

- Added flags for motion to time for 13 tracks instead of 9 on first attempt
  to acquire tracking.

- Added check of BRT flag byte before checking block type. This prevents 
  switch read to write from working incorrectly.

- Added code to execute subroutine to use search fields for backing up
  to position before the splice point for EOT side of filemark splices. 

- Added code to change color of LED (Steamboat/vail) depending on the
  type of tape (ie, density) we are writing.  

- For handling of multiple errors, changed order of reporting. Previously
  Unit Attention was reported, followed by the pending error. This
  caused bugs when an immediate command is aborted (by the hot+ button, 
  for example). Now, Unit Attention is reported after a pending error.  
  The complete new order is: NEXUS, RESERVATION CONFLICT, PENDING ERROR, 
  UNIT ATTN, LUN, other.

- Fix problem introduced with Log Select, 00 FSC was getting sent to the
  Fatal Error Handler due to count wiping the accumulator.

CUSTOMER UNIQUE ENHANCEMENTS:

- Changed the error light for code loads. Now, turns it off since fast blink 
  is for eject, on is for broken.  

- Added check for NAL if the following are true:
       1. Doing test unit ready with queuing option BUSY.
       2. We are not loading, unloading, ejecting, ready.
  This will insure that we report busy only if there is some hope of
  the state changing. If NAL is on and the drive is not doing anything, we 
  are not ready (cause not known, FSC C6).  

- Set most significant bit when flag indicates a fatal error. This is 
  required to set the correct FSC.  

COMPRESSION ENHANCEMENTS:

- Add code to not ignore ILI interrupt during Raw Read Mode.

01/31/92       KC01041X/KS020170=======================================
               ===

CARS ADDRESSED:

C-102: Hang on read

- Fixed a problem in the rewind manager which wasn't tracking CRC.

K-2600 - FSC 16 - media error in 8200 mode.

- Increased timeout value from 20ms to 140ms for reading 8200 DTM blocks

CODE ENHANCEMENTS (NO CARS ADDRESSED):

- Enhanced code for LOG SENSE.

COMPRESSION ENHANCEMENTS:
                                     
- Fixed problem with recovery procedure.

01/30/92       CC01041W/KS020170=========================================

Compression build.

01/30/92       KC01041V/KS020170=======================================
               ===

CARS ADDRESSED:

K-2604: Illegal request returned when reflecting Mode Select data from Mode
Sense.

- Added EEPROM bit which will allow the Host to do this (turn off errors of
illegal 
  change of density (at non-LBOT)). 

CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Added more midtape wakeup support.

- Slowed search back for write splice positioning down to 1.5x to improve
chances of tracking    at the splice point. 

- Clear the _HSS bit when issuing a high speed search stop on an abort.  

CUSTOMER UNIQUE ENHANCEMENTS:

- Added flag to tell servo that POST is complete (use for LEDs).

- Recoded Super HOT to be HOT+ unload.  

- Added code to generate a Unit Attention when the user inserts an
unsupported 
  media type.

01/29/92       CC01041U/KS020140=======================================
               ====

CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Fixed minor bug with log sense write counters.  

01/28/92       KC01041T/KS020140=======================================
               ====

CARS ADDRESSED:

C-0017: Mode sense compressed count incorrect

- add code to fix the compressed count for small logical blocks.
   
C-0018:  Request Sense information bytes are incorrect.

- In compression drives, IPORT does the residual calculations for variable 
  length read when the length is not correct. 

C-101: Hang on Space

- Fixed file search problem of 8200 mode on a compression drive where the BEN 
  IPORT was left on and loaded from a preceding read. This caused problems 
  for READ and SPACE commands since the data was from another part of the
tape.  

CAR - 1409, 2593 - Hang on Space

- Added bit to indicate some failure occurred and space should ignore the data

  in the buffer and start the search with a High Speed Search reverse.  

CAR K2587 - In Write Dammit mode write filemarks would run to PEOT.

- RBC is now ignored for WRITE DAMNIT tapes during write file marks.

CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- For Log Sense, changed the ECC value reported from 2 to 3 bytes.

- Added three counters for the SCSI Log Select command:
  Total Rewrites (LOGS_RWCNT), Total Bytes Processed (LOGS_BPCNT),and Total 
  Unrecoverable Errors (LOGS_UECNT). 

- Added generic configuration bits 
  1.  for converting operation code 1D (send diags) into a no operation.
  2.  for making operation code 3B (write buffer) illegal.

-  Mid tape WAKEUP support code - deleted the label xc_b_initdone,
   since it was declared as public/extern, but never used!

-  Fix to abort handling for read and the fill manager.

-  Added flag for space which indicates that the current buffer may be invalid. 


- Added code to read and clear the log sense values for dportw.
  These log values are returned by log sense and cleared by log select.

- added support for debug mode (TRACK CAPTURE): Change 8200 mode to ignore
  EOD block types.

- Disable read dammit during 8200 read retries

- fixed ECC reporting to correctly reflect blocks requiring ECC to be read
  from tape.

- Added a command handler to interpret a midtape wakeup command.

VERSION 41S was not released.

01/24/92       CC01041R/KS020110=======================================
               ===

Version 41R was a compression release.

01/24/92       KC01041Q/KS020110=======================================
               ===

CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Started development of midtape wakeup.

- Fixed mode select (paged mode) so that lengths 1,2, and 3 are flagged
  as mode select parameter list length errors (FSC = CC).  

- Added flags to tell Space that a soft error is being cleared by a Space or 
  Locate.

- Added flag for Low Speed Search (7.5x) which is used to position before 
  the splice point.   

- Fixed reselection timeout when we timeout on an queued command.  

- Fixed expiration of reselection tries so it aborts correctly. This can only
  occur if the MAXIMUM RESELECTION TRYS field in the EEPROM is non-zero. If
  the reselection fails, it now aborts correctly.  

- Normal EEPROMS allow the drive to attempt reselection forever. However, if
  the eeprom is set up top not allow reselection forever and an abort occurs, 
  we set a FSC. This allows the user to do a request sense and see that an 
  abort has occurred.  

- Changed abort to check first if we are doing high speed motion. If so, do a 
  high speed stop instead of a regular stop.  

COMPRESSION ENHANCEMENTS:

- Added code to fix problem with decrementing FORE_CNT to -1.

- Changed the Sense Keys for FSCs 18h and 19h from B to 4 (now hardware
error).  

01/21/92       CC01041P/KS020100=======================================
               ====

No change from 41N to 41P. 41N is generic and 41P is compression.

01/21/92       CC01041N/KS020100=======================================
               ====

CAR 2592 - Format error on a Space.

- Fixed 8200 back space block problem where the FILE_ID was incorrectly 
  causing IPORT to report a FORMAT ERROR.

CAR 2595 - Improper LUN handling.

- Fixed code to ensure clearing of LUN error flag.

CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Changed constant so that FSC DA is reported correctly.  

- Fixed code to report FSC D9 correctly. Previously reported CE.

- Fixed reporting of FSCs 1A and 1B for compression drives. 

CUSTOMER UNIQUE ENHANCEMENTS:

- Fixed reporting of FSC D0, D6, EA for mode select.  

01/17/92       KC01041M/KS020071=========================================

CARS ADDRESSED:

CAR 2512 - Hang on Read.

- Added setting of the block timeout during an overrun condition.
  Optimized data block read recovery processing for read dammit.
  Removed long and short FMs and EOD blocks from the ECC count returned
  through SCSI sense bytes as requested by manufacturing.
  Added 8200 rewrite statistic for debug.

CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Improved parity error handling in DPORTR.

- Added two mail messages (B_MTWAKEUP and XC_MTWAKEUP) which will
  coordinate communication between the BUSIF, MANAGER, and MIDTAPE
  modules. This is preliminary midtape wakeup enhancement activity.

- Optimized the manager's primary command dispatch table for commands
received
  from the BUSIF module and added one more command (XC_MTWAKEUP) for the 
  midtape wakeup function. The midtape wakeup message is preliminary work 
  only and does not change functionality.

01/17/92       CC01041L/KS030140=======================================
               ===

CARS ADDRESSED:

CAR 922 - Sense key bits not updated correctly during load.

- Added code to prevent the drive from reporting good status on repeated
test 
  unit readys and then doing a check condition on the next command. 

CAR 1393, 2525, 2573 - Motion hangs.

- When MOTION is still busy don't send any more commands.

CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Added flag to support Mid Tape Wakeup. 

- Fixed problem of permanent read errors following a filemark.       

01/14/92       CC01041K/KS030140=======================================
               ====       
CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Use routine to reset the drive following the successful use of a 
  HEAD SYNC tape. 

- Cleaned up overflow problem in code.

- Fix problem for space and switch read to write for compression drives.  

- Fixed a problem (8200 MODE) after a write Filemark. The LID and BID were not
  set to 0. Fixed a compression problem for handling small logical blocks.
   
01/14/92       KC01041J/KS020071=======================================
               ===

CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Added flag in external ram. This is used by to fix a problem with
synchronizing IPORT and    BUSIF on write buffer. 

- Added flag for future changes in the managers and MAIL to add more fault
symptom codes    for bank0 managers. This will be used as an overflow FSC
location when the returned value    is 3F.  

- Fixed bug where IPORT finished but BUSIF did not when doing WRITE BUFFER
command    and it is aborted (but may occur normally).

- Changed flag so that log sense/select is compiled for compression drives as
well as extended    address space drives. 

- Added external definition to allow access of routine in FUNCTLIB.ASM from
MAIL.ASM.     Fixes problem with send diags in C drives.  

- New development: Put changes into log sense/select which allows access and
zeroing of read    stats (log page 3).

- Fixed send diagnostics for the compression drives.

- Fixed problem of disconnect and never reconnect after writing a filemark in
8200.       

01/10/92       CC01041H/KS030050======================================
               ====

CARS ADDRESSED:

CAR 2569: 8C on a Back Space Block.

- Changed meaning of the forward index pointer back to its original meaning.

CAR 2571: Hang in Multi-Host environment.

- Fixed IPORT to not hold bus.

CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Fixed handling of buffer wrap in 8200 mode on 8500C (uses entire buffer).

- Fixed lost buffer problem when writing in 8200 Mode using BENC.                  
           

01/07/92       CC01041G/KS030050======================================
               ====

CARS ADDRESSED:

CAR 1447 - SCSI Bus hang on Read.
    2566 - Hang on Read.

- Added code to fix Read hangs.

CAR 2535 - HOST times out drive during Write at LEOT.

- Now we disconnect while emptying the buffer after crossing LEOT. 

CAR 2567 - 8C on a Forward Space Block.

- Added code to SPACE to reset IPORT for every Space command.

01/03/91       KC01041F/KS030050======================================
               ====

CARS ADDRESSED (8500):

1440 - Motion failed on command space.

- New holemode algorithm couldn't handling a read recovery within 1M of EOD 
  on a read. This occurred on short tapes and locates in area of EOD.

2561 - Hang on Read.

- Read retry count can now be any number between 00H and 0BH inclusive.

CARS ADDRESSED (8500C):

CAR 1439 - IUM conflict with MODE SELECT values. 

-  Added code to support (MODE SELECT) RED to be 01 (acts as 00). Also, 
   enforces (MODE SELECT) DDE to be 1 if ALLOW_RAW is off.

CAR 1443 - Read following LOCATE was returning incorrect logical block.

- Fixed problem with LOCATING to the current position. 

CODE ENHANCEMENTS (NO CAR ASSOCIATED):

- Added more code to support LOG SENSE.

COMPRESSION ENHANCEMENT:

- Added code to clear MODE SELECT compression flags when compression is not 
  enabled by the BOOT or by the EEPROM. This turns off compression for 
  the drive. This completes checking for compression consistency.

- Corrected a VERIFY problem.

12/31/91       KC01041E/KS030050======================================
               ====

COMPRESSION ENHANCEMENTS:

- Fixed LOCATE problem.

12/31/91       KC01041D/KS030050======================================
               ====

COMPRESSION ENHANCEMENTS:  

- Added bit that will convert a mode select density code of 0 to 8C.

- Added code to cause LED to operate correctly on 8500C. 

- Now when setting EC4 control register only touch the appropriate bits.

12/30/91       KC01041C/KS030050======================================
               ====

CARS ADDRESSED:

CAR 2518 - When a 15H Mode Select is issued, the 8200 returns a good status,
the 8500 returns and illegal request.  

- Changed mode select/sense to allow for new configuration in EEPROM 
  (Allow parameter list length to exceed actual in mode select).

- Changed mode select to allow emulation of 8200 mode when the parameter
  list length is greater than the actual bytes to be transferred. This is
  technically illegal but the 8200 did not care. This change requires
  a new EEPROM configuration for mode select/sense (value = 5). CF_BITS4,
  Bits 0-2 set to 101B in code level 41C or later.  

CAR 2448 - FSC 37 on a Forward Space Block.

- Changed read recovery algorithm to perform read retries on multiple 1K 
  blocks rather than a single block at a time. This change will decrease 
  the time to fill the drives buffer, and therefore stop the drive from 
  appearing to ignore the host for hours.

CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Fixed code so that Test Unit Ready does not return "funny" FSCs such as
  41h and 42h.  

- Fixed code to correctly handle the case where the FSC is returned as 0 
  when it shouldn't be returned (due to immediate commands).
 
- Added code to support new FSC (3D). This FSC will only allow rewind and 
  unload action commands. Changes are to prevent SPACE and LOCATE from being 
  allowed if FSC 3D has occurred.  

- Changed inquiry code to make it table driven. This change speeds up inquiry.

- Fixed abort due to SCSI parity error. Now, returns FSC E6 instead of 05. 

- Fixed code to not zero FSC on immediate commands when complete.

COMPRESSION ENHANCEMENTS:

- Added support for LOG SELECT/SENSE.  

- Fixed bug in mode select density code which did not allow for correct 
  density code selection under SCSI-I. 

- Corrected an initialization problem which occurred after a LOCATE/SPACE
command.

- Fixed IPORT bug involving 8040 REGISTER.

- Added more code to fix BENC handling of data integrity failure.

12/30/91       KC01041C/KS030050======================================
               ====

CARS ADDRESSED:

CAR 2518 - When a 15H Mode Select is issued, the 8200 returns a good status,
the 8500 returns and illegal request.  

- Changed mode select/sense to allow for new configuration in EEPROM 
  (Allow parameter list length to exceed actual in mode select).

- Changed mode select to allow emulation of 8200 mode when the parameter
  list length is greater than the actual bytes to be transferred. This is
  technically illegal but the 8200 did not care. This change requires
  a new EEPROM configuration for mode select/sense (value = 5). CF_BITS4,
  Bits 0-2 set to 101B in code level 41C or later.  

CAR 2448 - FSC 37 on a Forward Space Block.

- Changed read recovery algorithm to perform read retries on multiple 1K 
  blocks rather than a single block at a time. This change will decrease 
  the time to fill the drives buffer, and therefore stop the drive from 
  appearing to ignore the host for hours.

CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Fixed code so that Test Unit Ready does not return "funny" FSCs such as
  41h and 42h.  

- Fixed code to correctly handle the case where the FSC is returned as 0 
  when it shouldn't be returned (due to immediate commands).
 
- Added code to support new FSC (3D). This FSC will only allow rewind and 
  unload action commands. Changes are to prevent SPACE and LOCATE from being 
  allowed if FSC 3D has occurred.  

- Changed inquiry code to make it table driven. This change speeds up inquiry.

- Fixed abort due to SCSI parity error. Now, returns FSC E6 instead of 05. 

- Fixed code to not zero FSC on immediate commands when complete.

COMPRESSION ENHANCEMENTS:

- Added support for LOG SELECT/SENSE.  

- Fixed bug in mode select density code which did not allow for correct 
  density code selection under SCSI-I. 

- Corrected an initialization problem which occurred after a LOCATE/SPACE
command.

- Fixed IPORT bug involving 8040 REGISTER.

- Added more code to fix BENC handling of data integrity failure.

12/23/91       KC01041B/KS030050======================================
               ====

COMPRESSION ENHANCEMENTS:

- Add flag to handle data integrity problem.

- Fixed problem with double ABORTING IPORT.

- Fixed a flag conflict at LEOT between Read and Write Mode. 

- Added code to check for mode when not enabling IPORT interrupt. This con-
  flict caused IPORT Interrupt not to get enabled at idle loop when at LEOT.

12/19/91       KC01041A/KS030050======================================
               ====

COMPRESSION ENHANCEMENTS:

- Removed the speed throttle for the compression code. We can now go at 5.0
  MByte/sec.  

12/19/91       KC010419/KS020060======================================
               =====

CARS ADDRESSED:

CAR 2546: FSC 8C on a Test Unit Ready when POST failed. 

- Changed code to report error correctly.

CODE ENHANCEMENT (NO CARS ASSOCIATED):

- Added bit for fixing bug in parity error reporting. 

- Fixed the reporting of a parity error on Mode Select. 

CUSTOMER UNIQUE ENHANCEMENTS:

- Added bit to CF_BITS4 (bit #3). This will cause a Mode Select (and later, 
  a Log Select) to report with a FSC of E2 if a parity error occurs (instead 
  of a Restore Data Pointers).

COMPRESSION ENHANCEMENTS:

- Added code to clear compression status counters on a Rewind, Load, or Un-
  load.

- In Mode Sense, fixed the reporting of compression ratio.

- Added a test for illegal length interrupt from BENC when an IPORT suspends
  so the disconnect done message is not sent. Buffer needs to be filled so 
  the rest of the logical block in BENC can complete it's operation and free 
  up the bus.  

- Added code to return an FSC of E6 on a parity error in Mode Select. This is 
  turned on as a customer unique option if CF_BITS4, bit 3 is on. In normal 
  operation, Restore Pointers Message is sent instead.

- Added code to run IPORT at full speed during Read operations.

- Fixed timing window problem with servo.

12/16/91       KC010418/KS030050======================================
               ====

CARS ADDRESSED:

CAR 1425 - Hang on Read 8500 Density

- Compression wasn't handling Even Byte Disconnect during reads correctly. 


CAR 2550 - EE image fails to load with no indication back to HOST.

- Added FSC 67 for a code load problems. FSC can only be cleared with a power 
  on.

CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Corrected Mode Select so No Disconnect is turned off when the block size 
  is set to >28000h. 

COMPRESSION ENHANCEMENTS:

- Added code to handle Data integrity failure.

- Fixed problem with not reading all data before reaching EOD.

- Added code to indicate if logical read manager is doing a locate to 
  correctly position after a read abort.

- Added code to do a locate block when aborting a read so IPORT will 
  position correctly when using a compression BEN.  

- Changed code to default EBD off when the bit is off in EEPROM.  

- Fixed DPORTW Trace capability.

- Changed code so that long transfers will work on Adaptec (there is an 
  Adaptec bug at high speeds.)  

12/11/91       KC010417/KS020060======================================
               ====

CARS ADDRESSED:

CAR 1409 - Drive failed on a Space command.

- Added code to handle space/locate buffer searches. A new status is 
  returned and no residual calculation is done.

CAR 2523 - Wrong status posted on a failed load.

- An asynchronous error from servo wasn't handled correctly when processing 
  check conditions. Fixed code to fully process and return correct status.

CAR 2526 - FSC 8C on a Space back file command.

- Same fix as CAR 1409.

CAR 2528 - Software Hang

- Bad receipt of message or selection by WD chip. Recovery of the resulting 
  error was incorrect.

CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Holemode reverse enhancements: changed table values to support reverse 
  search using search fields in 8500 mode; changed motion to reverse search 
  rather than backhitch a set distance; removed compile flags to allow for 
  reverse search using search fields when in holemode.

- Added support for new FSC which will report a fatal media error. 

- Put the Formatter into 8500 mode when the Unload is done so that the Servo 
  correctly detects the next tape loaded.

- Fixed SUPERHOT button to override prevent media removal (as specified).   

- Default the drive into 8500 mode if an invalid or unsupported tape is 
  loaded into the drive.     

- Fixed code so if we are not at LBOT other legality tests (such as write 
  mode) will be done. 

- Added code for stopping an IPORT buffer search after 2 Meg to handle cases 
  where bad search field(s) caused High Speed Search to stop prematurely. 

- Write problems caused bad Search Fields to be written. If this occurs High 
  Speed Search is restarted. 

- Removed hang when a Not In Buffer Backward command is received after a 
  reverse search has already been done once. This can occur if a bad Search 
  field caused a reverse search to stop prematurely. 

- Make sure that the Unit Sense Bytes in request sense are set during 
  a hardware error. Before, info commands, such as Test Unit Ready, would 
  not report SSE (Byte 20, bit 1 of request sense data) if a servo hardware 
  error occurred asynchronously (ie, blocking a hole on the side of the 
  cartridge). Now, we will get SSE when the FSC is AD.

CUSTOMER UNIQUE ENHANCEMENTS:

- Added LED configuration flags.

- Added code to keep LED from blinking when a servo error occurs and the 
  unique LED configuration flag is set. 

- Changed the parameter settings for MTNSETDRV (normal is 1, and customer 
  unique settings are 2 and 4) to support new LED configurations. 

- Added code to support motion errors uniquely for customers (the amber 
  light turns and other lights aren't changed).

COMPRESSION ENHANCEMENTS:

- Removed special ILI handling which was added for old BENC.

- Added code to handle ILI for new BENC.

- Fixed problem with enabling transfer after detecting buffer empty.

- Fixed problem with extra LOADED-TO-NOT-LOADED interrupt which caused the 
  SCSI transfer to end when IPORT did not.

- Fixed problem with sending too many interrupts during a read operation 
  which caused the task queue to overflow.

- Fixed problem with Filemark detected just before a Read Command completed.

- Added code to reset IPORT after a Rewind.

- Added code to ensure that a flag is set before enabling ZERO FILL to 
  complete a partial physical block when writing a Filemark.

- Added bit in EEPROM (CF_BITS2, bit 3) for compression. 

- Changed the compression synchronous negotiation maximum speed from 5 
  MByte/Sec to 2.5 MBytes/Sec for BEN/WD chip bug which will be fixed in next
  turn of BENC. 

- Added code to reset BENC in the compression branch of BUSIF. 

11/27/91       KC010416/KS020030======================================
               ====

CARS ADDRESSED:

CAR 1395: Regression failed on test 210.

- Added flags to track drive mode. Problem was test sequence (209 then 210)
  caused a time out from the host because an immediate command was processed
  and executed before status was returned due to prior drive mode.

CAR 2515: Multi host problem.
 
- Fixed window where we could be selected while attempting to reselect and
  not do that properly. This window is < 5us long. A fix was made in
  code which removed a larger window and this bug is from K-2521 which
  comes from the same place as K-2515. The window should be closed now.

CAR 2516: Multihost problem.

- Fix to support multihosts during shutdown handling.  

CAR 2519: Customer couldn't handle early warning reported as deferred.
 
- Added EEPROM bit _LEOTNOTD in CF_BITS1.  This bit will turn off
  the deferred error condition for pending LEOT.
- Added EEPROM bit _LEDOPT in CF_BITS2.  This bit is for selecting LED
  customer unique configurations.
- Added code to allow reporting of pending LEOT (FSC 6) without the
  deferred error condition set in request sense.  

CAR 2521: Multihost problem.

- There still was a 5 micro-second window wherein incorrect processing of 
  commands could take place. Closed this window.

CODE ENHANCEMENT (NO CARS ASSOCIATED):

- Fixed bug in allowing buffered FM due to changing tape modes. 

- Clear the _STOP_HSS bit if we run into BOT or EOT on a HSS_STOP.

CUSTOMER UNIQUE ENHANCEMENTS:

- Added code and EEPROM bit to prevent media eject during a write buffer.  
- Allow button to eject tape if failure on write buffer occurs. This 
  overrides any Prevent Media Removal.

11/21/91       KC010415/KS020030======================================
               ====

CARS ADDRESSED:

CAR 2503: I/O timeout from HOST while reading a blank tape. 

- Revised logic to not test for blank tape three times. 

CAR 2507: WRITE command hangs drive in no disconnect mode.

- Fixed the shutdown manager during no disconnect.

CAR 2508: Codeload fails but there is no LED indication of failure.

- Fixed code so that it indicates failed load with correct LED sequence.

CAR 2511: Incorrect inquiry after reset. 

- Use revision level in memory during reset.

CAR 2515: Multihost command handling logic problem.

- Fixed logic to keep track of commands in Multihost environment and to pre-
  vent reselection/selection collisions.

CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Added flag for space to decide to go back to HSS.

- Added counter to count false HSS stops to forward & reverse direction.

- Added code for 20 MHz SIF card synchronous negotiation limits.

- Fixed a problem with Prevent/Allow media removal.

11/15/91       KC010414/KS020030======================================
               ====

CARS ADDRESSED:

CAR 2510: FSC 3A during Mode Space File when 8500 appends in 8200 mode to
          existing type.

- Change threshold in servo to recognize ;power amplitude ATM's.


CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Fixed write replying before disconnect done. 

- Added procedure for stopping and searching in reverse during a read/
  recovery.

- Added code to configure Readbuffer command (3Ch) as illegal.  

- Added support for 2 byte even byte disconnect.

- Fixed a HSS reverse problem for holemode backhitches.

- Fixed an abort handling problem where SCSI interface doesn't send a 
  disconnect done.

- Turned on code for ECC with flag.

- Changed the way that the servo code version label is checked. (For the 
  support of multiple Hardware/Servo from single control Code Line).

11/07/91       KC010413/KS012010=======================================
               ===

CARS ADDRESSED:

CAR 1334: 3rd party target problem.


CAR 2456: Hang on Back Space file.


CAR 2468: Hang on Rewind.


CAR 2484: Hang on Write to PEOT.

- Physical write would not abort correctly.

11/06/91       KC010412/KS012010=======================================
               ===

CARS ADDRESSED:

CAR 2473 - Multihost

- Fixed bug where motion does a shutdown when rewind is not active but re-
  wind sent an unexpected status to the command handler.


CAR 2474 - Software hang on write to PEOT

- We now check whether or not we are at PEOT buffer starting fill manager.

CAR 2489 - Incorrect ASC/ASCQ when LEOT is detected after single write.

- Changed the ASQC from 0 to 2 for an FSC of 6.

CAR 2495 - Read timeout/software hang

- Added flags and new test to both read and write for an abort problem when 
  SCSI Interface is sent a terminate and had not completed a reconnect.

CODE ENHANCEMENTS (NO CAR ASSOCIATED):

- Corrected incompatibilities in file ID and file number indicated in EOD.

- Fixed problem where the physical write manager would not abort correctly.

- Added code to support filemarks in directory area (for new 8500 Directory 
  Support.)

- During Abort, bus could hang. This was corrected by setting and clearing 
  a flag after a command that can have other commands sent within it to the  

  SCSI interface code.

- Added code to set flags when a servo error of AC or AD occurs. This allows 
  reporting servo errors that occur independent of host initiated commands.

CUSTOMER UNIQUE ENHANCEMENTS:

- logic change for cleaning cartridge support.

10/25/91       KC010410/KS011990========================================

CARS ADDRESSED:

CAR 2482 - Code load tape would not load.

- Fixed bug where motion does a shutdown when rewind is not active but re-
  wind sent an unexpected status to the command handler.

CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Added configuration support for accepting filemarks in directories.  

- Added support to HSS for File marks in directory area.

- Modification which no longer require a motion command to be active when 
  receiving a shutdown. 

- Removed the Synchronous negotiation GO SLOW code. No EEPROM change is 
  needed. The Western Digital FIFO offset is set to 11 (from 12) to elim-
  inate A3 errors.

- Added vendor unique page 21 for Mode Sense and moved the compression 
  status page to 22.

- Remove assumption that 8200 BBID hi is zero. Use all 10 bits.

- Added background CRC for 20 MHZ units only.

10/21/91       KC010400/KS011970=========================================

CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Fixed problem where if door closed without tape after a code load tape
  is ejected, the door would not open if button pushed. The problem was 
  corrected by clearing AUTOLOAD when ejecting the load tape. 

- Fixed problem for SUPERHOT button (enabled). The door would not open if 
  there wasn't any tape in the drive. 

- Changed Write Splice parameter from 00h to 02h for 8500 Mode.

- Added code to allow write buffer to be done in parts. When a write buffer
  is done in parts, no other commands can be processed (except Inquiry and 
  Request Sense). Only the initiator which started the write buffer opera-
  tion can send write buffer commands. FSC = EB for rejected commands. 
  Added check to see if we actually did all of the code load. When we get 
  the message that the write buffer is complete. This is needed for write 
  buffer in parts.

- Took out conditionals so Write Buffer for parts is always compiled.

- Fixed calculation of Read/Write retry counter.

- Added code to clear Write Buffer phase when an error is received on 
  return from last write buffer. Currently, abort of write buffer oper-
  ation will require reset to clear state of machine.


10/18/91       KC0103VE/KS011960=======================================
               ===

CARS ADDRESSED:

CAR 2476: Reporting of tape size is incorrect.

- Fixed cartridge sizing. 

CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Fixed reconnect threshold and No Disconnect bit compatability.

- Fixed write delay time to force it into the range of 0..3FFF. (Mode Select) 

- Added code to the Initiate Synchronous Negotiation message sequence to 
  handle abort sequences. 

- Added new EEPROM configuration bits for SCSI synchronous transfer rate 
  control and for the autosizing of tape near LEOT. 

10/14/91       KC0103VD/KS011922=========================================

CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Fixed bug where we think it is a verify by mistake.

- Added code to Mode Select to check that the logical block size is
  divisible by four (0 or variable is divisible by 4). If not divisible by
  four then Even Byte Disconnect is forced to off. This is necessary 
  because odd size blocks with Even Byte Disconnect set on can hang the 
  drive. This condition (EDB = on and odd size blocks) is illogical. 

10/14/91       KC0103VC/KS011922=========================================

CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Fixed disconnect problem where we did not disconnect in some circumstances.

10/08/91       KC0103VB/KS011921=========================================

CARS ADDRESSED:

CAR 2464: Hang during a space backward command.

- Fixed HSS logic problem when hitting Beginning Of Tape.


CODE ENHANCEMENTS (NO ASSOCIATED CARS):

- Added bit to fix load from tape bug (ejects tape).

10/07/91       KC0103VA/KS011920=========================================

CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Added variables for change to codeload from tape.

- Fix problem that causes all 8200 Logical IDs to be zero.

- Change unload procedure to not rewind first after load tape finishes.

10/04/91       KC0103V9/KS011910=======================================
               ===

CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Fixed Mode Sense to allow receive of less pages of data than requested
  (as long as each page or block descriptor is fully transferred).

- Removed the check that bytes 15&16 of search fields are zero in the 
  VALIDATE routine. This was done in preparation for a format change for 
  SETMARKS. 

- Fix Write routine for 8500 mode so the current Logical ID is not updated 
  for rewritten block.

- Skip current Logical ID update if we are in 8200 mode write.

- Skip testing Logical ID for 8200 Logical ID sequence checking subroutine
  in write.

CUSTOMER UNIQUE ENHANCEMENTS:

- Corrected vendor specific (via EEPROM) code in mode sense.

10/03/91       KC0103V8/KS011910=======================================
               ===

CARS ADDRESSED:

CAR 2128/1298 - Hang on a Read.

- Added a counter to indicate that a block read was already marked as a per-
  manent error.


CAR 2453 - Multihost hang on write filemark.

- Added code to handle changes in the disconnect privledge based upon each 
  Host's requirements.  

CAR 2455: Hang during autoload when HOST sends Test Unit Ready.

- Changed logic to address problem.

CAR 2462:  No disconnect on an 8200 mode Write Filemark command.
 
- We now disconnect. 

CAR 2463: Hang on Space

- Fixed problem wherein we hit Beginning Of Tape during 75X HSS.

CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Added new servo interfaces and commands (MTNPOSTALT, MTNOVRDATA).

- Added support for SUPER HOT BUTTON.

- Added flags for 8200 back space block problem where an ATM was detected 
  during a stop back hitch command. This forces a blank sense to get out 
  of the erased area and back to the data. This prevents the no tracking
  problem we have been seeing. 

- Removed special case for EOD on read

- Added handling to account for lost Filemarks and Logical blocks. 

- Changed how INFO BYTES are copied to save the machine state.

- Added FSC to saved state.  

- Added task reschedule entries for use by mode sense output code.

- Changed the default from Odd Byte Disconnect to Even Byte Disconnect. No
  change to EEPROM, rather the meaning of the bit was changed.

- Fixed zero return in 8200 mode of under/overrun counter in request sense.

- Added code to set the new density codes for all products. Density is also 
  sensed for these codes. Code to do mode select of page F still not 
  completed.

- Changed Mode Sense, Request Sense, read position, and read block limits
  to use table driven code. This saves code space, improves synchronous
  transfer rates for fast machines (close to 50% time saved on data trans-
  fire for these info commands), and improves readability.  

- Added SCSI interface module task reschedule entries for Mode Sense table 
  code.

- Fixed bug in write by enabling interrupts in correct subroutine.

- Change routine to get even Block ID Logical ID from Header Logical ID field 
  and to get odd Block ID Logical ID (lo) from the checksum location of BRT. 
  Checksum (not used) moved to byte 0 of BRT. (Checksum and Logical ID (lo) 
  swapped places.)

- In Write, we now mask interrupts around Buffer Index accesses to protect 
  certain variables during IPORT Interrupt accesses.

- Changed servo interface (alerts servo when POST is complete).

- Added changes to BRT format with DPORTW.

- Added CRC support.

CUSTOMER UNIQUE ENHANCEMENTS:

- Corrected bug in customer's initiate synchronous negotiation feature.  
  The negotiated values were not being converted into the WD chip's requir-
  ed format correctly.  

- Added customer unique Test Unit Ready.

- Added support for customer unique LED configuration.

09/26/91       KC0103V7/KS011910=======================================
               ===

CODE ENHANCEMENTS (NO CARS ADDRESSED):

- Added support for multi-host cleaning requirements.

- Add code to determine which read recovery pass is sucessfull in recover-
  ing a block.

- Added track counter to allow the future implementation of an algorithm 
  that bans read retries within some distance of a permanent error.

- Modified motion to servo interface.

- Added definitions for the "RRR" - Reverse Retries Required bit. The RRR 
  bit is returned to the Host in bit 5 of USB 2 via the Request Sense 
  command.

- Added support for drive needs cleaning, drive was cleaned.

- Fixed bug which caused D5 and D7 FSCs to not generate correctly. Only 
  occurs on send diags and 8200 only mode.

- We now check more unsupported bits for 0 in Mode Select.

- Fixed DCC based on hardware type.

- Changed Write to force two complete GAP stripes (Trk 1 then Trk 2) at a
  Stop-Start.

CUSTOMER UNIQUE ENHANCEMENTS:

-  Added support for cleaning to report check condition. 

09/20/91       KC0103V6/KS011900==========================================

CARS ADDRESSED:

CAR 2443: Hang on Write. 8500 never returns status after data out phase dur- 
          ing a Write.

- The flush manager link was not being updated; now we update a new message 

  for each new SCSI command sent.

CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Improved space back to LBOT efficiency. 

- Fixed a write problem involving block IDs.

- On a stop back hitch, if we find an ATM send a trigger to the space manager 
  saying we detected an ATM.

09/19/91       KC0103V5/KS011900=======================================
               ===

CARS ADDRESSED:

CAR 2426 Locate was slamming into LBOT in certain sequences. 

- Fixed logic problem to set fLAG to point at
  the brt before call of I_SET_FLID. 

CODE ENHANCEMENTS (NO CARS ADDRESSED):

- Lowered maximum time the SCSI task holds the processor when waiting to
  send an information byte. This does not affect the read path.

- Fixed P5 bit reporting in page 20 of Mode sense.

09/19/91       KC0103V4/KS011900=======================================
               ===

CARS ADDRESSED:

CAR 1327: Media error during Write Filemark.

- Added code to clear the 8500 bad pair flag when writing 8200 Filemarks.  

CAR 2420: Hang during Test Unit Ready while loading tape.

- For cleaning cartridge, the ready bit was set wrong.

CAR 2421 - Hang on Space Back

- Closed window where an ATM_DETECTED between the sending of a stop and 
  getting a stop done.  

CAR 2437 - Hang on Read

- Added fix to handle a permanent read error after a filemark.

CODE ENHANCEMENTS (NO CARS ADDRESSED):

- Fixed DPORTW for monitor reliability.

- Fixed a cleaning cartridge load problem.

- Fixed a codeload tape problem

- Changed macro to copy 8 bytes to synchronous negotiated values.

- Changed Mode Select to ignore WTF and RTF (and old reset mode) fields 
  except for the high bits of WTF and RTF (ie, we check bits 7 and 4 for 0).

- Converted internal FSC 59 to FSC 3 (can occur on Send Diag).

- Change to provide information on the quality of the read on all blocks 
  that get transferred into the BRT.  

- Improved code efficiency in DPORTW.

- Reorder Direct and Indirect DPORTW variables for Monitor readability.
  (Affects how they are initialized.)

- Fix bad block tests for data block type discovered by compression testing.

- Added support for primary status changes of 0xFF, 0x5A, 0xC6, and 0x03 in
  Motion.

CUSTOMER UNIQUE ENHANCEMENTS:

- Added support for a new unique inquiry situation. The additional sense
  length for this inquiry is 74H for a total of 121 bytes.

09/16/91       KC0103V3/KS011880=======================================
               ===

CARS ADDRESSED:

CAR 1332: Drive hangs after setting max burst in Mode Select.

- Added a new SCSI interface module bit to correct bus contention between 
  SCSI and IPORT.  

CAR 2433: Density code incorrectly reported for 8200 written tapes.

- Changed Mode select to correctly report density.

CODE ENHANCEMENTS (NO ASSOCIATED CARS):

- Fixed "switch read to write is too long" problem.

- Moved the SCSI/IPORT interlock bit from external RAM to direct RAM
  for speed considerations.  

- Put in split up write buffer

- Correctly set the FILE_ID on a wrong DTM failure.  

- Fixed queuing problem to allow commands to queue after reset or load.

- Modified EEPROM code to run time check.


CUSTOMER UNIQUE ENHANCEMENTS:

- Added code for a 5 millisecond time-out not the standard 250 millisecond 
  time-out.  

09/11/91       KC0103V2/KS011860=======================================
               ===

CODE ENHANCEMENTS (NO CARS ASSOCIATED);

- Fixed tape load sequence to allow changes in density when the tape is 
  in the drive but is not loaded.  Also fixed reporting of tape status for
  the same condition.  

- Fixed problem in mode select of density 14h when tape is not at LBOT.

- Hardwired DCC in page F (Data Compression page of Mode Sense) to 0.

- Changed Mode Select/Sense so RTF and WTF fields are larger and the reset
  mode field is eliminated. Fixed REW reporting in page 10h.  

- Fixed FSC 3A to get information bytes from the Space Manager.

- For the UNLOAD command, if the _NAL bit is set and LOADED is not set, 
  issue an unload to servo instead of a rewind and unload.

09/10/91       KC0103V0/KS011850=======================================
               ===

CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Changed ASC for FSC D4 back to 1A (was 24).

- Added tape reverse retries required feature. This feature is reported in 
  Request Sense and cleared on unload. ("RRR" bit in Request Sense)

- Closed window for Test Unit Ready to accurately report unit attention.

- Added code to ignore search fields when tape is not moving.

- Moved determination of drive state for READY to SCSI interface module. 

- Added code to support "Drive Requires Cleaning" reported in Request Sense.

09/06/91       KC0103U3/KS011840=======================================
               ===

CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Fixed a logic problem in HSS. If we aren't moving, we now return to the 
  correct routine.
                
09/05/91       KC0103U2/KS011830=======================================
               ===

CARS ADDRESSED:

CAR 2279: 8500 writes in wrong density

- Added mask for density.

- Changed mode select and mode sense for using the EEPROM defined
  density bits of 15h. We still allow 85H on mode select but 15H is
  returned for 8500 mode in mode sense. 

- Added flag to keep density mode consistent when appending or creating to an
  existing tape. 

CAR 2412: Hang on Send Diagnostics 

- Added code to save and restore the synchronous negotiated values after a 
  Send Diagnostics' "Warm" reset has occurred. The order of the initialization 
  sequences were changed to ensure that the restored values were not
reinitil-
  ized by the start-up code.

CODE ENHANCEMENTS (NO CARS ASSOCIATED):

- Fixed aborting of the fill manager. 

- Fixed send diagnostics (test 2) to write correctly (including EOD).

- Fixed writing Filemark (immediate). We now have the Filemark manager ignore 
  the completion of the physical side if we have already sent back status.

- Fixed bus hog problem by disconnecting on a read.

- Fixed a bug in the physical write manager if we shutdown and are not busy.

- Added code to maintain the tape density across an unload/load sequence.

- Added code to the Test Unit Ready command to always return BUSY when the 
  state of the servo is unknown (during post). This is to fix a window
  that can occur when the Host sends a command and servo has yet to indicate 
  whether or not there is a tape in the machine.

- Added MANAGER, SCSI interface module consistency check for links and flags 
  associated with disconnect. These modifications are associated with 
  aborting.

- Decreased maximum servo timeout for rewind from 10 minutes to 6 minutes. 
