Not an expresssion of disgust because I added a photo to my profile I hope. :D rather Yet Another CDrom Question.
I have managed to get a CDrom player to play audio CDs (Not MP3) thanks to all the examples pointed to by people on this forum, including Ken Wilson's (Pic), YAMMP3 and others. I'm having a bit of bother with the Fast forward and Fast rewind command which does not work. I seem to remember that it is an optional feature so not all player may support it, but I have tried it on 3 different players and the command always comes back with a sense key of 05 and an ASC of 20 which means that it is an illegal command. YAMMP3 seems to do it by simply skipping 10 seconds of play every 100ms and issuing continuous play command in order to achieve the above. I'm a doing something wrong with the command? Is there something I'm overlooking? I'm attaching the relevant piece of code in the hope that someone can H.E.L.P! By the way he MSF value is only a few ms old when it gets sent to the command and the AtaPacket is cleared after sending the packet out .
ldi r16,0x10 ;Bit 4 of byte 1 set indicates
sts AtaPacket+1,r16 ;backward scanning
;Byte 1=0 for forward
ldi r16,0xba ;ATA Command
lds r16,TrackCurrentMSF_M ;Start scanning from current location
sts AtaPacket+3,r16 ;Set minutes in r16
sts AtaPacket+4,r16 ;Set seconds in r16
sts AtaPacket+5,r16 ;Set frame in r16
ldi r16,0x40 ;(0100 0000) AMIN, ASEC and AFRAME
sts AtaPacket+9,r16 ;format