3)The device shall stop generating DSTROBE edges within tRFS of the host negating HDMARDY-.

4)If the host negates HDMARDY- within tSR after the device has generated a DSTROBE edge, then the host shall be prepared to receive zero or one additional data words. If the

host negates HDMARDY- greater than tSR after the device has generated a DSTROBE edge, then the host 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 device.

5)The host shall resume an Ultra DMA burst by asserting HDMARDY-.

5.5.3.4Terminating an Ultra DMA data in burst

a)Device terminating an Ultra DMA data in burst

The following steps shall occur in the order they are listed unless otherwise specifically allowed (see 5.6.3.5 and 5.6.3.2 for specific timing requirements):

1)The device shall initiate termination of an Ultra DMA burst by not generating DSTROBE edges.

2)The device shall negate DMARQ no sooner than tSS after generating the last DSTROBE edge. The device shall not assert DMARQ again until after the Ultra DMA burst is terminated.

3)The device shall release DD (15:0) no later than tAZ after negating DMARQ.

4)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.

5)The host shall negate HDMARDY- within tLI after the device has negated DMARQ. The host shall continue to negate HDMARDY- until the Ultra DMA burst is terminated. Steps (4) and (5) may occur at the same time.

6)The host shall drive DD (15:0) no sooner than tZAH after the device has negated DMARQ. For this step, the host may first drive DD (15:0) with the result of its CRC calculation (see 5.5.5):

7)If DSTROBE is negated, the device shall assert DSTROBE within tLI after the host has asserted STOP. No data shall be transferred during this assertion. The host shall ignore this transition on DSTROBE. DSTROBE shall remain asserted until the Ultra DMA burst is terminated.

8)If the host has not placed the result of its CRC calculation on DD (15:0) since first driving DD (15:0) during (6), 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 device has asserted DSTROBE and negated DMARQ and the host has asserted STOP and negated

HDMARDY-, and no sooner than tDVS after the host places the result of its CRC calculation on DD (15:0).

C141-E116-01EN

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Fujitsu MPG3XXXAH-E manual Terminating an Ultra DMA data in burst