From: [EMAIL PROTECTED] on behalf of Hale Landis
Sent: Tue 12/7/2004 4:53 PM
To: [EMAIL PROTECTED]
Subject: RE: [t13] ATAPI Overlap and Queuing
This message is from the T13 list server.
On Tue, 7
Dec 2004 15:42:21 -0800, Mark Overby wrote:
>This message is from the T13
list server.
>I can firmly state that there are at least two host
controllers on the
>market that support command queuing for ATA devices in
hardware.
OK, then I would agree that O/Q should not be removed for
either PATA
ATA or ATAPI devices.
But this is such a mess...
*
Old style O/Q maybe supported by some PATA ATA devices and maybe by
some PATA
ATAPI devices (MKE note: The PACKET command supports old
style PATA O/Q. Note
everyone: The R/W DMA QUEUED commands are the
PATA O/Q commands for for ATA
devices).
* Is old style O/Q supported by SATA for SATA ATA or SATA
ATAPI
devices? Is there any reason old style O/Q can not be made
obsolete
for SATA?
* Is new style queuing (is that NCQ?) supported for
SATA ATAPI? If
so, what changes have been made for this (new version of the
PACKET
command, or new options of the PACKET command)? Is there a
definition
of new style queuing (NCQ?) for SATA ATAPI? If not, why
not?
Hale
*** Hale Landis *** www.ata-atapi.com
***
