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2) The device shall pause an Ultra DMA burst by negating DDMARDY-. 3) The host shall stop generating HSTROBE edges within tRFS of the device negating DDMARDY-. 4) If the device negates DDMARDY- within tSR after the host has generated an HSTROBE edge, then the device shall be prepared to receive zero or one additional data words. If the device negates DDMARDY- greater than tSR after the host has generated an HSTROBE edge, then the device shall be prepared to receive zero, one or two additional data words. The additional data words are a result of cable round trip delay and tRFS timing for the host. 5) The device shall resume an Ultra DMA burst by asserting DDMARDY-. 5-86 C141-E050-02EN 5.5 Ultra DMA Feature Set 5.5.4.4 Terminating an Ultra DMA data out burst a) Host terminating an Ultra DMA data out burst The following stops shall occur in the order they are listed unless otherwise specifically allowed (see 5.6.4.10 and 5.6.4.2 for specific timing requirements): 1) The host shall initiate termination of an Ultra DMA burst by not generating HSTROBE edges. 2) The host shall assert STOP no sooner than tSS after it last generated an HSTROBE edge. The host shall not negate STOP again until after the Ultra DMA burst is terminated. 3) The device shall negate DMARQ within tLI after the host asserts STOP. The device shall not assert DMARQ again until after the Ultra DMA burst is terminated. 4) The device shall negate DDMARDY- with tLI after the host has negated STOP. The device shall not assert DDMARDY- again until after the Ultra DMA burst termination is complete. 5) If HSTROBE is negated, the host shall assert HSTROBE with tLI after the device has negated DMARQ. No data shall be transferred during this assertion. The device shall ignore this transition on HSTROBE. HSTROBE shall remain asserted until the Ultra DMA burst is terminated. 6) The host shall place the result of its CRC calculation on DD (15:0) (see 5.5.5) 7) The host shall negate DMACK- no sooner than tMLI after the host has asserted HSTROBE and STOP and the device has negated DMARQ and DDMARDY-, and no sooner than tDVS after placing the result of its CRC calculation on DD (15:0). 8) The device shall latch the host's CRC data from DD (15:0) on the negating edge of DMACK-. 9) The device shall compare the CRC data received from the host with the results of its own CRC calculation. If a miscompare error occurs during one or more Ultra DMA bursts for any one command, at the end of the command, the device shall report the first error that occurred (see 5.5.5). 10) The device shall release DDMARDY- within t after the host has IORDYZ negated DMACK-. 11) The host shall neither negate STOP nor negate HSTROBE until at least after negating DMACK-. tACK 12) The host shall not assert DIOW-, CS0-, CS1-, DA2, DA1, or DA0 until at least tACK after negating DMACK. C141-E050-02EN 5-87 Interface b) Device terminating an Ultra DMA data out burst The following steps shall occur in the order they are listed unless otherwise specifically allowed (see 5.6.4.11 and 5.6.4.2 for specific timing requirements): 1) The device shall not initiate Ultra DMA burst termination until at least one data word of an Ultra DMA burst has been transferred. 2) The device shall initiate Ultra DMA burst termination by negating DDMARDY-. 3) The host shall stop generating an HSTROBE edges within tRFS of the device negating DDMARDY-. 4) If the device negates DDMARDY- within tSR after the host has generated an HSTROBE edge, then the device shall be prepared to receive zero or one additional data words. If the device negates DDMARDY- greater than tSR after the host has generated an HSTROBE edge, then the device shall be prepared to receive zero, one or two additional data words. The additional data words are a result of cable round trip delay and tRFS timing for the host. 5) The device shall negate DMARQ no sooner than tRP after negating DDMARDY-. The device shall not assert DMARQ again until after the Ultra DMA burst is terminated. 6) The host shall assert STOP with tLI after the device has negated DMARQ. The host shall not negate STOP again until after the Ultra DMA burst is terminated. 7) If HSTROBE is negated, the host shall assert HSTROBE with tLI after the device has negated DMARQ. No data shall be transferred during this assertion. The device shall ignore this transition of HSTROBE. HSTROBE shall remain asserted until the Ultra DMA burst is terminated. 8) The host shall place the result of its CRC calculation on DD (15:0) (see 5.5.5). 9) The host shall negate DMACK- no sooner than tMLI after the host has asserted HSTROBE and STOP and the device has negated DMARQ and DDMARDY-, and no sooner than tDVS after placing the result of its CRC calculation on DD (15:0). 10) The device shall latch the host's CRC data from DD (15:0) on the negating edge of DMACK-. 11) The device shall compare the CRC data received from the host with the results of its own CRC calculation. If a miscompare error occurs during on...

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