RE: [t13] ATA-8 APT Teleconference

[Curtis Stevens]

Title: Re: [t13] ATA-8 APT Teleconference

Regarding the obsolescence of ATAPI overlap and queuing.  I am looking to remove as much dead wood from ATA8-ACS as I can.  At the time I had not seen nor heard of any implementation of ATAPI overlap and queuing.  I sent messages to the T13 reflector and only got encouragement to obsolete the capability.  I attended T10/MMC for 2 consecutive meetings where manufacturers of ATAPI devices actually attend.  I managed to get one confession that the capability was implemented in a device.  They then stated that the drive was in a vendor specific environment and saw no reason for the capability to be documented.  When I asked for a straw poll, everyone at the MMC meted appeared to be in favor of obsoleting the capability.   I do not want to maintain capabilities in ATA8-ACS that are no longer or have never been in use.   Regarding TCQ, I believe that the time will come to obsolete the capability from ATA, but it is my understanding that there are still drive manufacturers shipping it, and host controllers using it.  I suspect sometime, possibly in ACS-2, that it will be reasonable to obsolete this.       ------------------------------------------------- Curtis E. Stevens 20511 Lake Forest Drive #C-214D Lake Forest, California 92630 Phone: 949-672-7933 Cell: 949-307-5050 E-Mail: [EMAIL PROTECTED] Ambition is a poor excuse for not having enough sense to be lazy.   From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Mark Overby Sent: Monday, November 14, 2005 3:29 PM To: Hale Landis; forum@t13.org Subject: RE: [t13] ATA-8 APT Teleconference   As I stated in the telecon call, the draft with those changes will be available by the 21st of November. Descriptions of the feature set and IDENTIFY words are in the ATA8-ACS document. My changes are soley to the ATA8-APT document describing the parallel interface. I suggest you read the latest rev of ATA8-ACS. I believe I already noted to Curtis that the IDENTIFY words were now wrong and he was going to fix in the next rev.   We have a joint T13 / T10 meeting in January in Phoenix to go over all of the packet material to ensure that it is accurate and correct with reality.   I believe the reason it was obsoleted was to simplify ATA8-ACS for ATAPI, but you'd have to ask Curtis for his reasoning behind it - it was his motion to obsolete.   There are discussions ongoing about allowing "NCQ" like functionality for packet devices.   From: [EMAIL PROTECTED] on behalf of Hale Landis Sent: Mon 11/14/2005 1:07 PM To: forum@t13.org Subject: Re: [t13] ATA-8 APT Teleconference This message is from the T13 list server. Mark Overby wrote: > Answers inline below: [...] > *** The feature set(s) as described in clause 4.19 and 4.20  of > ATA-7. This is more than an "editorial change"... When will the marked up versions of all the changes be available? That is changes to 4.19, 4.20, IDENTIFY data words, PACKET command, SERVICE command, and protocol diagrams, etc. > *** Both are being removed. I agree that removing one made no sense > without removing the other. This was voted on at the April 05 plenary > meeting and is recorded in the minutes. Curtis Stevens sat in on an > MMC meeting in March 05 in Dana Point and there as no objection. OK. But why remove this just for ATAPI? So what if no one implements it. If this old PATA attempt at 'tagged command queuing' is OK for disk drives why is it not OK for ATAPI devices? > *** I fully disagree that the overlap and queuing feature sets have > not been implemented at the host level. I know of 3 hosts I > personally have examined that implement this feature set. Queueing > and overlap is only being removed for packet command set devices. Just curious... Why is there no 'NCQ' for ATAPI devices? Is this a continued attempt to 'force' the ATAPI people out of T13 (and SATAIO?) and make them move to other interfaces (like USB) by restricting what they can implement? Hale -- ++ Hale Landis ++ www.ata-atapi.com ++