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Hi all, Does anybody know why the definition of the term "DRQ data block" changed from ATA/ATAPI-7, vol 1, rev 3c 3.1.42 DRQ data block: This term describes a unit of data words transferred during a single assertion of DRQ when using PIO data transfer. A data block is transferred between the host and the device as a complete unit. For all PIO data transfer commands except READ MULTIPLE, WRITE MULTIPLE, and PACKET, a DRQ data block is one sector, 512 bytes. For READ MULTIPLE and WRITE MULTIPLE commands the DRQ data block is the number of sectors indicated in word 59 of the IDENTIFY DEVICE response. For PACKET command the DRQ data block for transfer of the command packet is the number of bytes indicated in word 0 of the IDENTIFY PACKET DEVICE response. to ATA/ATAPI-7, vol 1, rev 3d 3.1.44 DRQ data block: This term describes a unit of data words transferred during a single assertion of DRQ when using PIO data transfer. ? Given the lost sentences in ATA/ATAPI-7, rev 3d, how shall host and device determine the exact size of a DRQ data block? Since both host and device need to agree on the size of a DRQ data block, this is an essential definition. Did this information move somewhere else? Thanks, Alex.
