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Dear all, CFA feature set implemented ATA device may support 8-bit data transfer. Through SET FEATURES command, 8/16-bit data transfer mode is switched. Therefore, 8-bit mode may be used by CFA WRITE MULTIPLE WITHOUT ERASE and CFA WRITE SECTORS WITHOUT ERASE commands. When a CFA feature set supported ATA device has 8-bit data transfer enabled, do all PIO data-in/out commands use only DD[7:0] for data transfer or all commands still use 16-bit data bus except for CFA commands (the 5 ATA defined CFA commands and CFA command codes B8h to BFh)? For example, is 8-bit or 16-bit bus used for data transfer of the READ DMA command when 8-bit mode is enabled? Best regards, Kepler
