Why I can not set CD speed?

Hi,

I have a question on setting CD speed. I have tried to get the write speed by sending GET Performance command to the drive. After that, I got the list of writting speeds. Then I use SET CD SPEED commands to set the speed of drive and monitor the real writting speed. I found a strange phenomena: Once I set the minimum speed and do some writing operation, after that even I reset it with the maximum speed, the DVD/CD drives still use the minimum speed. Why? Is there somebody ever encountered this situation.
Thanks,

Erica

What burning program are you using?

Hi garfiled, It might help if you list the CDBs you are issuing to the drive. Also, does the slow speed get fixed once you reboot?

RM

The process is like below. I just give some commands based on the source code and possible they are not the real tracing, since I do not know how to do tracing:

46 02 01 07 00 00 00 00 10 00 (Get Configuration CDB)

AC 00 00 00 00 00 00 00 00 00 03 00 (Get Performance)

or

AC 10 00 00 00 00 00 00 00 00 00 00

AC 00 00 00 00 00 00 00 00 03 03 00 (Get Performance)

or

AC 10 00 00 00 00 00 00 00 03 00 00

Here, sometimes, there are errors like the performance data length is not equal to that we got at the first time ;

54 01 00 00 00 00 00 00 00 00 (SEND OPC INFO)

Repeat begin

52 01 00 00 00 01 00 30 00 (Read Track Info)

B6 00 00 00 00 00 00 00 00 (Set Streaming)

1B 00 00 00 01 00 (Start Command)

Call Device.Write to write something ;

35 00 00 00 00 00 00 00 00 (sync cache) ;

Repeat end ;

Thanks

[QUOTE=RichMan;2237810]Hi garfiled, It might help if you list the CDBs you are issuing to the drive. Also, does the slow speed get fixed once you reboot?

RM[/QUOTE]