Firmware Release Notes

This document details all firmware changes made to the DM-xx24 series drive.  At the
time of this document, interim firmware revision 1.1d is the latest change.   
                                        Changes
                                        Affected
       
       1.03 9/3/92     Auto speed reduction change at read 
                       error detection.  Auto switch operable 
                       without performing a device reset.  
                       Change Definition parameter altered to 
                       support speed change.  Mode sense page 
                       code 2 and E supposedly fixed. SCSI xfer
                       timeout reset added.
       
       1.04            Fixed minor SCSI Interrupt Handling.
       
       1.05 10/27/92    Fixed Selection anomaly.  Incorporated automatic low speed
                        to high speed switching.  Modified calculation 
                        of Lead-Out address for increased efficiency.  Fixed Read 
                        Header command anomaly. 
        
        1.06 11/18/92   Allowed drive to properly negotiate Synchronous 
                        Transfer.  Fixed a minor problem with data block size transfers smaller
                        than 2048 bytes.  Modified Spindle motor braking algorithm
                        to increase reliability during seek operations.
        
        1.08  1/26/93   This change incorporated many fixes and enhancements
                        including:
                        - Photo CD-Multi-Session Support.
                        - Limited support for Connect/Disconnect.
                        - Decreased processor initialization time.
                        - Allowed disc to recognize up to 99 audio tracks.
                        - Returned good status (pacified) for a prevent/allow media  
                          removal command.
                        - Support Read Extended (28h) with transfer length = 0.
                        - Support to play first frame of first audio track.
                        - Increased reliability of LASER optics power management.
                        - Support for Linked Command and Relative Addressing***
                        - SCSI reset detection.
                        - 1 block disconnect/reconnect temporary fix.
                        - Pre-fetch support.
                                         
        1.09   2/8/93   Delayed processor initialization so that drive system 
                        power could settle first.  This version fixed initial problem caused
                        by version 1.08.

        1.10   4/28/93  Again several fixes:
                        - Fixed mis-calculation of sub channel MSF data.
                        - Fixed Mode Select Page Code E. 
                        - Corrected Read Sub Channel to indicate correct audio        
                          status of 'No Audio Status to Report' vice 'Audio Paused'.
                        - Fixed anomaly with Connect/Disconnect.
                        - Fixed problem with Arbitration
                        - Support for SCSI Abort command
                        - Corrected Pointer Messages




	1.11  9/14/93  Last Firmware change fixes all outstanding issues:


			- CPU utilization decrease by 15%.
			- Fixed double UNIT ATTENTION caused by 1.1
			- Support SCSI ABORT command
			- Improvement of TOC recovery
			- Mode parameters change to default at reset
 			- Fix for several SCSI command infractions
			- Fixed problem with 3rd layer ECC	
			* This firmware does not allow L-EC to be turned off
 	 


Developer Application Notes
All firmware revisions below 1.1 need to use the Audio Control command (C9h) instead of the SCSI-2 
Mode Select/Sense Page Code (0Eh).  The Page Code (0Eh) in the previous firmware releases did not
work reliably.  This bulletin applies only for DOS specific drivers only.  Owners of multi-tasking
operating systems (OS/2, NT, UNIX, etc.,) should upgrade to firmware 1.1.  This latest firmware version
takes care of possible drive malfunction during large file transfers.  Therefore, full implementation of
Page Code E can be included without concern of previous firmware levels.

Note Concerning Firmware Revision 1.11
The DM-xx24 series drive is no longer in production.  Therefore, it is believed that this firmware revision
represents the last efforts to resolve all outstanding issues.  However, during the SQA of this firmware 
we found that the L-EC cannot not be disabled as stated in PAGE CODE (01h) of the SCSI reference manual.  The
disabling of L-EC is only needed when a CD-I type disc (MODE 2, FORM 2) is used.  This format is rarely
used and shall not be a problem for any end users.

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