#	START NEW ARIX SCCS HEADER
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#	@(#) README: version 25.1 created on 11/27/91 at 14:41:29
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#	Copyright (c) 1990 by Arix Corporation
#	All Rights Reserved
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#	@(#)README	25.1	11/27/91 Copyright (c) 1990 by Arix Corporation
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#	END NEW ARIX SCCS HEADER
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This scsi's code was base on base.5.10.

BUG FIXED:(after base.5.10)

 05/10 rmt0(non_rewind tape) will cause system died.
	set timer for SPACE function in 'stp_strat.c'

 05/10 Use 'geteblk' to get buf for local reguest. And 
	each drive has their own buf and buffer.

********************* 
 05/10 temp feature: SECTOR 0 is in block number 1000.
*********************
 05/11 The xfer rate on sync mode has been changed to get
	4M bytes/sec xfer rate.

 05/15 In scsi_dbint.s(scsi_db_intr()), After return from called routine,
	it pop out parameters from stack was wrong.
	changed from mov (%sp)+, (%a1) to
	add 4, &sp;

 05/15 Define a macro in  scsi_log.h to handle log intiger type of 
       parameter.

 05/15 Allocate scsi command mailbox.
	Use constents define to set number of elements of command mailboxes.
 05/16 Start to merge old code.
 05/17 Make new release (scsi.5.17 ).
 05/17   Error recovery for unexpected disc.
 05/18   Modify all log statements to use LOG_LONG_WORD if necessary
 05/23   Timeout recovery is done.
 05/24   bug fixed : reverse cable.
 05/24   Change NCR chip register definition.
 05/25	 bug fixed : the number of scsidev entries has to be 16 instead of
 05/26   Make flaxable of initiator scsi bus id.
 05/31   parity error handler 
 06/02   add new interface routine in low level scsi driver to return error
	 message pointer.
 06/05   Multiple ioctls/opens done.
 06/12   scsiedt disk slice table compatible.
 06/19   residual count fixed on disk.
 06/26   To include "sys/ioctl.h" in high level driver.
 06/26	 temp fixed : return fixed UNIX type for all slices.
 06/26	 bug fixed : set_slice_table.
 06/26	 reject to set slice table if drive is scsi edt format.


06/26	 new release 6.26 **************************************

06/28	Reduce number of calls of timeout and untimeout for performance issue.
06/29   Nine Track Done.
07/06 	modified tape driver.
07/06 	Fixed archive tape problem.(for sometime unit attention was not set
	when changing media)
07/10	Modified cdb structure to make code readable. (add new headfiles:
	common_cdb.h, sdk_cdb.h and stp_cdb.h).
07/11   To make Exabyte work as nine track tape(change mediatype routine).
07/11	fixed edt disk access problem.(make read write access for all slices).
07/19	Made extra driver for exabyte.
07/26	Changed disk driver to support 3 1/2" IBM disk.
08/01   Fixed scsi_dequeue routine accessing address 0 problem.
08/03	Fixed read/write request across slice boundary.

08/03	new release scsi.8.3 *******************************************


08/07 Fixed bug to send abort message to wrong target
08/07 Fixed unit attention error.
08/11 Experiment: Use sel with atn command to send abort message instead of
                  using sel with atn and stop command. 
08/14 Fixed: using short filemark for exabyte and doing retry after drive
             report busy.

08/15 Fixed: makefile-- CFLAGS = -DSCSI_LOG instead of -DSCSI_LOG=YES

09/06 New disk layout done.
09/06 auto alignment slice boundary.
09/07 New DMA strategy done
09/12 Changed to new error code list
09/13 Merge exabyte source code with tape source code to one and
      generate two different object files
09/14 Fixed bug: DMA count error.
09/14 Fixed : IBM disk block count was wrong.
09/14 Fixed : format function didn't work in ioctl.
09/14 Added passthrough driver.
09/14 Change space.c makefile to fit with base.9.13.
09/14	new release scsi.9.14 *******************************************
09/15 Fixed: ioctl GET_NUM_TRACK cause system bus error on EDT format disk.
09/18 Fixed: Command timeout cause system hung! sometimes.
09/21 Setup init routine called in system startup time.
09/22 Call cache_disable routine in init routine.
09/22 Allocate command mailbox in open routine and deallocate in close routine.
09/22 Implement cm->act and cm->disc_count.
09/26 Reorgnize structure of scsi directory: 
	scsi/head is a public head directory.
	eliminate exabyte dir.
	change llvl to dsdb.
09/28 Fixed: blk_ratio field is cleared when doing close function.
10/9  Fixed: Fixed tape retention problems (system crash) causing by reorg 
	     structure.
10/17 Implement: Removeable media drive
		 open flag
10/17 Fixed: Handling scsi phase more flexable then before.
10/23	new release scsi.10.23 *******************************************


10/27	Fixed: fix problem of that mode select command does not set right.
10/27	Fixed: In open routine, if read operation does not work, set
	disk in not format status and return without error.
10/30	Fixed: Checking request queue in close routine. Doing close until
	nothing in the request queue.
11/10   system crash when access not on line tape 3 times( deallocate command
         box problem.)
11/10	Fixed: WORM drive problem, After bus reset the next selection of drive
	causes system crash.
11/13   Handle unnecessary reselect from drive(reset bus ).
 
11/13	Modify tape and disk driver to eliminate some macrois defined in
	hlvl_macro.h
11/14   Fixed : RRH case-- After sending DISC message, the phase go to 
	message out instead of bus free. Sending NOP message to fill out
	message out phase.
11/14	Fixed: If previous open get disk not formatted, then current open
	should read slice table in and verify if disk is formatted or not.
11/15	Removed some ioctl functions, such as set slice table, format,
	get num tracks , get num cylinders etc.,. Also, add get dev type.
11/15	check write protect in open routine.

11/15	Call the media init routine when open count is 0 in disk open.
	This change is to associate pass thru driver.
***** copy to /iopm/tonyw/scsi45 and ../struct *****
 12/11 Fixed Bus timeout problem: When channel is waiting for disconnect,
	and bus timeout happened; don't do untimeout for command.
12/13	includes cdrom
********* New release ************************************************
12/15   Fixed: If select timeout happened when trying to send abort message,
	untimeout command timer is not necessary.
12/15	Fixed: Raise interrupt level when issue_cmd is called by timer
	interrupt routine.
12/18	Enhenced: Add sar information in disk driver.

01/04	delete unnecessary assert in sdk_open which cause system crash.
******** relase to p6 **********************************************
01/20   Fixed 128k data xfer
01/20   Fixed: If disk drive response with recoverred error, ignore it !
01/20	Fixed: change one block r/w timer to 1 ms and BASIC timer = 10 secs
01/25   Enhenced: If getting blank check,zero out the block and return with
	no error.
01/25   Enhenced: check fuse if timeout happened.
******************

PLANES to DO:
******************
01/27	Enhenced: setup page 01 whenever bus reset or first open on device.
02/01   Support prtvtoc
