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The last mail was not very clean about the problem I have. Let me explain it in the details : I am doing an udmaout, and I am looking to the completion of the burst, following the sector number requested. (not to a termination or a pause during the transfer) I see that the first which detects that the transfer is finished is the device. So the device negates DDMARDY-. The next step is that my host asserts the STOP before receiving the DMARQ from the device. I would like to know if this behaviour could occur, and if the host has not to assert STOP because the device starts the termination protocol. (In this case, I have to modify the state machine of my host) According the chapter 9.14.4.2 f), you say that the host shall assert STOP within tli, AFTER the device has negated DMARQ. I think something is missing when the device and the host starts the termination protocol, changing the state of STOP and DDMARDY- at "the same time." Stephane. [EMAIL PROTECTED] wrote: > This message is from the T13 list server. > > Hi Hale, > > What exactly is it that you think is missing? Clause 6.6.2.3 in ATA/ATAPI-6 > provides an excellent overview of Ultra DMA burst termination phase rules > (even if I do say so myself). The content of this clause has been in every > A/A standard since the introduction of Ultra DMA. This clause reads: > > 1) Either a sender or a recipient may terminate an Ultra DMA burst. > 2) Ultra DMA burst termination is not the same as command completion. If an > Ultra DMA burst termination occurs before command completion, the command > shall be completed by initiation of a new Ultra DMA burst at some later time > or aborted by the host issuing a hardware or software reset or DEVICE RESET > command if implemented by the device. > 3) An Ultra DMA burst shall be paused before a recipient requests a > termination. > 4) A host requests a termination by asserting STOP. A device acknowledges a > termination request by negating DMARQ. > 5) A device requests a termination by negating DMARQ. A host acknowledges a > termination request by asserting STOP. > 6) Once a sender requests a termination, the sender shall not change the > state of STROBE until the recipient acknowledges the request. Then, if > STROBE is not in the asserted state, the sender shall return STROBE to the > asserted state. No data shall be transferred on this transition of STROBE. > 7) A sender shall return STROBE to the asserted state whenever the sender > detects a termination request from the recipient. No data shall be > transferred nor CRC calculated on this edge of DSTROBE. > 8) Once a recipient requests a termination, the responder shall not change > DMARDY from the negated state for the remainder of an Ultra DMA burst. > 9) A recipient shall ignore a STROBE edge when DMARQ is negated or STOP is > asserted. > > If this isn't sufficient, excruciating detail on exactly what is supposed to > happen in each specific case of Ultra DMA burst termination is provided in > clauses 9.13 and 10.2.4. > > If, after reading these clauses, you have any additional questions about > Ultra DMA burst termination, please feel free to call or send an email to > me. In addition, I have found that using the "find" function in Word or > Acrobat is most helpful when looking for specific details about something > like this in these documents. > > Regards, > > Mark Evans > Maxtor Corporation > 500 McCarthy Boulevard > Milpitas, CA 95035 USA > Tel: 408-894-5310 > Cell: 408-391-7805 > FAX: 408-324-7432 > email: [EMAIL PROTECTED] > > -----Original Message----- > From: Hale Landis [mailto:[EMAIL PROTECTED]] > Sent: Monday, November 26, 2001 7:51 AM > To: T13 List Server > Subject: Re: [t13] Command completion of an UDMA OUT burst ... > > This message is from the T13 list server. > > On Fri, 23 Nov 2001 18:36:46 +0100, Stephane Cattaneo wrote: > >I have a question regarding the completion of a burst in udma out. > >Who has to do the termination protocol ? The device or the host ? > > Here again is an example of something that is missing from the > ATA/ATAPI-x documents. I have lost count of the number of times this > question has been posted to the T13 list server. Anyone want to > attempt to provide the missing information? Anyone know where the > missing information should go in the document? > > *** Hale Landis *** [EMAIL PROTECTED] *** > *** Niwot, CO USA *** www.ata-atapi.com *** > > Subscribe/Unsubscribe instructions can be found at www.t13.org. > Subscribe/Unsubscribe instructions can be found at www.t13.org. Subscribe/Unsubscribe instructions can be found at www.t13.org.
