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I have an ATAPI DVD drive that is < 3 months old that exhibits this behavior. (Actually I have two, both from different manufacturers) Conveniently, since I have the host and interrupt controller under my chipset I can probe both lines. The INTRQ line on the ATA interface fires, the interrupt fires in the chipset, and then the status is read with BSY still asserted and the INTRQ becomes unasserted again. I'll dig out the hard drive I have that exhibits this behavior, I don't remember how old it was. -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Hale Landis Sent: Wednesday, November 17, 2004 3:27 PM To: [EMAIL PROTECTED] Subject: Re: [t13] BSY and INTRQ at end of command This message is from the T13 list server. Mark Overby wrote: >I agree with you, Hale, that if a SATA host does this while emulating >PATA, it is a non-compliant host. However, on the PATA side I have seen >multiple devices that do this. The host has to be tolerant of that >behavior and deal with it (most certainly in SW). Hmmm... I have never seen a device (even the most poorly implemented ATAPI devices) assert INTRQ *before* setting BSY=0. This would be a very badly broken device and not likely to work on very many systems. Are you talking about a device you saw 15 years ago or something more recent? And are you sure you where not seeing false INTRQ assertions detected by a host's interrupt controller due to noise on the INTRQ signal line? I've seen this. But this isn't the problem we are talking about here. Hale -- ++ Hale Landis ++ www.ata-atapi.com ++
