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On 4/25/02, Hale Landis <[EMAIL PROTECTED]> wrote: >.... >As soon as the device has status of BSY=0 DRQ=0 the command is >completed at the interface, the actual writing to the media may not >be done yet but that doesn't matter, the device is ready to receive >the next command from the host. >.... You might also want to wait for INTRQ. Some devices get unhappy if you send the next command before INTRQ has been sent. Most operating systems wait for the interrupt by default. But if you have some embedded application or low level control of the registers then it's best to wait for INTRQ ( or the bit in the host interface chip which indicates that INTRQ was received ). Actually, if the op sys doesn't already do it for you, it might be wise to check INTRQ ( either the actual interrupt or the interface chip register bit) BEFORE reading ALT STATUS to check for completion. ...Harlan
