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Hi all, I have difficulties with the proper spec interpretation of the "11.12.3.2 Host pausing an Ultra DMA data-in burst" chapter of ATA/ATAPI-7 V2. I question the following scenario: 1) An UDMA burst is running (more than 1 data items were strobed by the device already) 2) The host deasserts HDMARDY# to pause the burst 3) The device stops strobing 4) The host asserts HDMARDY# to resume the burst 5) The host deasserts HDMARDY# again after a very short time to pause the burst because some internal condition changed Note, that the device does not strobe any data between 4) and 5). Is the host violating the spec in 5)? The spec states "a) The host shall not pause an Ultra DMA burst until at least one data word of an Ultra DMA burst has been transferred.". I guess the word "burst" is unclear here. My understanding of "burst" is "everything starting with burst initiation until end of burst termination". If this interpretation is correct, then the host is allowed to do 5) because there was data transferred in this burst before 2). I appreciate your help. Thanks, Alex.
