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Mark Overby wrote:
I object to removing queuing. Overlap I don't object to.
Hmmm... Just to make sure we are talking about the same thing and because there has been a long-standing confusion...
There are two versions of "overlap"... One version is when a device supports queing but the queue depth is only one - this can work on both ATA and ATAPI devices. The other version is defined only for ATAPI devices and it uses the DSC bit with "immediate" commands.
I say that all forms of queuing (including the case of queuing with a queue depth of one) for both ATA and ATAPI devices can/should be made obsolete (because I don't think anyone is currently shipping a host controller product that can support any form of queuing as defined by ATA/ATAPI-x, x=4, 5, 6 or 7). I do not think the non-queuing version of overlap (using the DSC bit on ATAPI devices) should be made obsolete.
Hale
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++ Hale Landis ++ www.ata-atapi.com ++
