Fujitsu MHV2080AS, MHV2060AS, MHV2040AS manual Terminating an Ultra DMA data in burst, Dmarq

Interface

2)The device shall pause an Ultra DMA burst by not generating DSTROBE edges.

NOTE - The host shall not immediately assert STOP to initiate Ultra DMA burst termination when the device stops generating STROBE edges. If the device does not negate DMARQ, in order to initiate ULTRA DMA burst termination, the host shall negate HDMARDY- and wait tRP before asserting STOP.

3)The device shall resume an Ultra DMA burst by generating a DSTROBE edge.

b)Host pausing an Ultra DMA data in burst

1)The host shall not pause an Ultra DMA burst until at least one data word of an Ultra DMA burst has been transferred.

2)The host shall pause an Ultra DMA burst by negating HDMARDY-.

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.

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