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SO my current understanding is then besides the Device Reset command, Identify Packet Command, and Packet command, all other commands for ATAPI devices come from the SCSI / MMC group.
(notice I said commands, not protocols... PIO / DMA, SRST, Status, Error reg, etc)
Whoa.
1) Various power managing BIOS do not discriminate between ATA/ ATAPI, so ATAPI devices end up receiving the power management commands: Idle, Standby, Sleep, etc. ATA/ ATAPI Sleep in particular has no clear SCSI equivalent for the bus-specific function of floating pins.
2) ATAPI != MMC. The op x12 "INQUIRY" byte 0 mask x1F PDT ("Peripheral Device Type") is not always x05 = C/DVD = MMC. x01 = Tape, x00 = super floppy are popular. Any of x 0E 07 05 meaning super floppy are theoretically allowed, and x0E = RBC is present in 1394/ ATAPI designs. Etc.
Pat LaVarre
