Fujitsu MPG3XXXAH manual The data in transfer, Pausing an Ultra DMA data in burst

Models: MPG3XXXAH

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11)The device shall drive the first word of the data transfer onto DD (15:0). This step may occur when the device first drives DD (15:0) in step (10).

12)To transfer the first word of data the device shall negate DSTROBE within tFS after the host has negated STOP and asserted HDMARDY-. The device shall negate DSTROBE no sooner than tDVS after driving the first word of data onto DD (15:0).

5.5.3.2The data in transfer

The following steps shall occur in the order they are listed unless otherwise specifically allowed (see 5.6.3.3 and 5.6.3.2 for specific timing requirements):

1)The device shall drive a data word onto DD (15:0).

2)The device shall generate a DSTROBE edge to latch the new word no sooner than tDVS after changing the state of DD (15:0). The device shall generate a DSTROBE edge no more frequently than tCYC for the selected Ultra DMA Mode. The device shall not generate two rising or two falling DSTROBE edges more frequently than 2tCYC for the selected Ultra DMA mode.

3)The device shall not change the state of DD (15:0) until at least tDVH after generating a DSTROBE edge to latch the data.

4)The device shall repeat steps (1), (2) and (3) until the data transfer is complete or an Ultra DMA burst is paused, whichever occurs first.

5.5.3.3Pausing an Ultra DMA data in burst

The following steps shall occur in the order they are listed unless otherwise specifically allowed (see 5.6.3.4 and 5.6.3.2 for specific timing requirements).

a)Device pausing an Ultra DMA data in burst

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

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-.

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C141-E112-01EN

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Fujitsu MPG3XXXAH manual The data in transfer, Pausing an Ultra DMA data in burst