Matshita/Panasonic CW-7502

This drive will only produce useful disks with the recent firmware revision X.17. The X depends on the drive hardware revision.

Thanks to Jeroen Steenblik <jeroens@esrac.ele.tue.nl> for adapting the generic-mmc driver to the CW-7502 recorder. He spend a lot of time and wasted many CD-Rs until it was obvious that the pre-X.14 firmware does not completely comply with the SCSI-3/mmc standard.

Here are Jeroen's notes for upgrading the firmware:
The update can be found at the Plasmon technical website, http://tech.plasmon.co.uk/, choose 'Download Files' and obtain the X.17 firmware for the CDR480. This includes all instructions. One thing I might add, when downloading the two files in the sequence described in their document, my drive refused the second file. I had to reboot after downloading the first file and only then I could download the second. Quite scary stuff. Swapping the download sequence should prevent this (so I've read).

Memorex CR-622

Submitted by Bryan E. Chafy <bchafy@ccs.neu.edu>:

The drive as shipped comes with firmware that does not support DAO. The firmware lives on a PROM, it is not flashable. You need an EPROM burner, a 27c020 PLCC EPROM, and the D4.0 ROM image for the CRW-1622 (can download it from Memorex web site, the name of the image is d39e.dat).

The ROM is socketed at the rear of the drive, you will see it when you remove the top cover. Mine had a sticker on it with the numbers E07/885B.

Note, this is for the CR-622 (and its sister the CDR-622 wearnes drive), NOT the CRW-1622. The CRW-1622 drive is flash-upgradeable).

IMHO, Wearnes/Memorex should be sending us new ROM's free of charge because the box clearly states the CR-622 supports DAO.

The new firmware does not turn the CR-622 into a cd-rw capable drive. You can still only burn cd-r media.

Yamaha CDR400t, CRW4260

These drives sometimes have problems with writing at 4x speed. The resulting disk is hard read for some reason. Disks written at 1x or 2x speed are fine. Yamaha's support is aware of this problem. It might be related to the actual firmware revision. I successfully wrote CD-Rs at 4x speed with a CDR400t using firmware revision 1.0k.

HP CD-Writer+ 75XX, HP CD-Writer+ 8XXX, HP CD-Writer+ 9XXX, SONY CRX100

The firmware restricts the possible disk types in multi session mode (DAO only) to one of the following:

• Pure audio CD.
• CD-EXTRA where the 1st session contains only audio tracks and the 2nd session contains 1 data track.

Further restrictions:

• The length of the 1st track's pre-gap is restricted to a certain amount.
• Cue sheets with ISRC codes are rejected of the COPY flag is set. This might be fixed in future versions.

SONY CD-R CDU948

The firmware restricts the possible disk types in DAO mode to one of the following:

• Pure audio CD.
• Mixed mode CD where the 1st track is a data track followed by at least 1 audio track.
• CD-EXTRA where the 1st session contains only audio tracks and the 2nd session contains 1 data track.

The length of the 1st track's pre-gap is restricted to a certain amount, too. If you want to create a pure data CD you will have to append a dummy audio track to the toc-file, e.g. with:

TRACK AUDIO
PREGAP 0:2:0
SILENCE 0:4:0