This message is from the T13 list server.
On Fri, 24 May 2002 14:36:49 -0600, Pat LaVarre wrote: >This message is from the T13 list server. >Hale L: >For the ignorant (lazy?) like me, can you easily/quickly >confirm/deny in English ... > >Technically the published protocol requires a UDma receiver to >tolerate a sender that sends a CRC for every two-byte "word" it >sends. Where do you see that? In the state diagrams when you get to states DMA1 or DPD4 you are at the point where the host DMA engine and the device are going to transfer some number of DMA data bursts. The DMA bursts follow the appropriate DMA protocols and timings. >And the published protocol requires a UDma sender to tolerate a >receiver that asks for a CRC with every two-byte "word" it >receives, except that the sender has some freedom, rising with >burst rate, to send some extra "word"s included in the CRC before >the CRC. A UltraDMA burst might have only one word. Most UltraDMA bursts are going to have many more words. >(Might be nice if I knew what STOP meant. I might know more if >we hadn't chosen to rename the pins every so often. That history >has meant that the bus traces I see in passing use any of a >number of different names to discuss each pin & bit & byte.) STOP is a state within the UltraDMA protocols. *** Hale Landis *** www.ata-atapi.com ***
