		Firmware Release History
		for Yamaha CDR400t, CDR400tx,
		CDR400t-NB, & CDR400AT
		CD Recorders







Changing Contents for Firmware for production of CDR400xx
Version NO.:1.0m Inquiry Date: April 13, 1998

Revised version of the standard is supported for 4x writing.

Fixing problems of the new media standard:
1) Recorded medium complying with this standard are reported
   to be unreadable with some CD-ROM drives if data is recorded
   in ISO9660 format. 

   This version of the firmware solved this problem.
	*There are no problems with the following.
	-- ISO9660 recorded in Disk-at-once mode.
	-- ISO9660 recorded in Track-at-once mode, with single 
	   session and the "Close Disc" setting
	-- Other formats such as CD-DA.

The firmware version 1.0L was not officially released.

                                
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Changing Contents for Firmware for production of CDR400xx
Version NO.:1.0k Inquiry Date: Feb.20.'98


Some audio CD players could not play back recorded CD's or could not
select tracks when played back.  
This revision corrected this problem.

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Changing Contents for Firmware for production of CDR400xx
Version NO.:1.0j Inquiry Date:Oct.27.'97

1) There was a possibility that the system could hang up and that the
tray or caddy did not eject when using the Star_stop command (Immediate=1).
The revision corrected this problem.

2) A revision was made so that the system does not hang up even when
the buffer underrun occurs during the DAO (Disc At Once) / SA) (Session
At Once) writing.

3) A revision was made so that the system does not hang up when a series
of DAO/SAO test mode writing is executed in a row.

4) A revision ws made to give the correct value for the ISRC code when reading.



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Changing Contents for Firmware for production of CDR400xx
Version NO.:1.0i Inquiry Date:Oct.27.'97

1) Disc eject operation is improved.
When the Eject button was pressed while the Tray open/close command was
being executed, occasionally
the tray would not eject. This problem has been fixed.
2) When recording was started by the Write command and OPC (Optimum
Power Control) was about to
be executed, the SCSI bus would not disconnect.
This problem has been fixed.
3) In order to avoid any problem that could occur on Power Macintosh 4400 or
Performa 6410.
4) We have fixed the problem which had caused the system to freeze in DAO
(Disc At Once) or SAO
(Session At Once) recording modes when the Sync Cache Command was
executed in an attempt to record
a small amount of data in the range of 300 blocks (632 Kbytes).
5) The problem of the system freezing can be fixed as follows. In the Windows 95
My Computer, execute
the Media command Eject, and simultaneously press the "EJECT" button of the
CD-recordable drive to
eject the tray. Then load the tray manually.


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Version No.: 1.0g Inquiry Date: August 6, 1997

Changing Contents from the previous version.

1) Bug Fix
1-1) Some bugs of the following commands were fixed. Read Disc Information
command, Read CD Recorded Capacity command, Read TOC information
command, Mode Select Write Parameter mode page, and Read CD command.
1-2) Load/Eject command operation occasionally caused the hanging up of drive.
1-3) In case of only Session At Once (including Disc At Once ), the recording
quality may not have been the best if the actual write process was just after the test
mode write process. The results may vary depending on the media. The bug of
version 1.0e and 1.0f for CDR400/CDR200 is related to this bug. In the case of
these firmware versions, no data was recorded if the actual write process was just
after the test mode write process at SAO.
1-4) CDR200 only. The audio track which was recorded by CDR200 at Track
At Once had a problem to play-back on CD Player.

2) Improvement
2-1) Buffer Empty Ratio was changed to improve the performance of recording. (
The setting, 92% is changed to 40% )


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Changing Contents for ROM for production of CDR400xx

Version No.: 1.0d Inquiry Date:Apr.30.'97

Changing Contents from the previous version.

1) Solved reselection Problem on SCSI bus.
2) Solved reselection Problem on disc insert check time .
3) More than 2MB of "packet CD" capacity which originally has as basic function.


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Changing Contents for ROM for production of CDR400xx

Version No.: 1.0c Inquiry Date:Mar.12.'97

Changing Contents from the previous version.

1) Common firmware for caddy and tray models.


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Changing Contents for ROM for production of CDR400xx

Version No.: 1.0b Inquiry Date: Feb.21 '97

Changing Contents from the previous version.

1) The Win95 eject command is now supported. (Right mouse button)
2) Abort during DAO test mode is now supported.
3) The problem that occurred when the packet size exceeded the buffer size
during packet recording has
been fixed.
4) Measures were taken regarding the inability of the host to recognize the
CDR400 when the host is
rebooted under Win95 or NT with a disc present in the CDR400.
5) For a SCSI write command which receives data from the host, disconnect was
not performed in some
cases. This has been fixed.
6) An Eject Sense Command is now supported to detect when the front panel
eject request switch is
pressed while medium removal is disabled.
7) A bug in which the disk ID was not recorded during packet recording has been
fixed, so that this data
is now recorded.
8) The bug which caused errors to occur when reading packet recorded data has
been fixed.
9) A problem with buffer under-run processing has been fixed.
10) Measures have been taken regarding a problem which slowed down CDDA
reading.

 

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First Shipping Firmware Release ROM for production of CDR400xx

Version No.: 1.0a - First Production Shipping version.