This message is from the T13 list server.
Hi Stephane, As I wrote to Hale, I think that everything about Ultra DMA that needs to be defined is in clauses 6.6, 9.13, 9.14, 9.15, and 10.2.4. However, to answer your specific question: Item (f) in 9.14.4.2 states, "The host shall assert STOP within tLI after the device has negated DMARQ. The host shall not negate STOP again until after the Ultra DMA burst is terminated." Table 69 gives the minimum value of tLI as 0 ns. Therefore, if a host asserts STOP before the device negates DMARQ, the host is in violation of the standard. I'll admit that the standard does not often specify what is to happen when a host or device violates a protocol. In most cases I would say that the results are indeterminate. Can you provide any additional details about the effect of the host asserting STOP before the device has negated DMARQ? If you have any additional questions about Ultra DMA burst termination, please feel free to call or send an email to me. Regards, Mark Evans Maxtor Corporation 500 McCarthy Boulevard Milpitas, CA 95035 USA Tel: 408-894-5310 FAX: 408-324-7432 email: [EMAIL PROTECTED] -----Original Message----- From: Stephane Cattaneo [mailto:[EMAIL PROTECTED]] Sent: Friday, November 23, 2001 9:37 AM To: T13 Subject: [t13] Command completion of an UDMA OUT burst ... This message is from the T13 list server. Folks, 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 ? Imagine that the device will start the protocol of termination, asserting DDMARDY-, then what happens if the host asserts the STOP signal before the device de-assert DMARQ ? (This is my case) Also, who has to do the termination protocol at the completion of an udma in ? (in case of either the device or the host starts, what happens ?) Thanks a lot for your help. Regards, Stephane. Subscribe/Unsubscribe instructions can be found at www.t13.org. Subscribe/Unsubscribe instructions can be found at www.t13.org.
