9)The device shall assert DDMARDY- within tLI after the host has negated STOP. After asserting DMARQ and DDMARDY- the device shall not negate either signal until after the first negation of HSTROBE by the host.

10)The host shall drive the first word of the data transfer onto DD (15:0). This step may occur any time during Ultra DMA burst initiation.

11)To transfer the first word of data: the host shall negate HSTROBE no sooner than tLI after the device has asserted DDMARDY-. The host shall negate HSTROBE no sooner than tDVS after the driving the first word of data onto DD (15:0).

5.5.4.2The data out transfer

The following steps shall occur in the order they are listed unless otherwise specifically allowed (see 5.6.3.8 and 5.6.3.2 for specific timing requirements):

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

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

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

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

5.5.4.3Pausing an Ultra DMA data out burst

The following steps shall occur in the order they are listed unless otherwise specifically allowed (see 5.6.3.9 and 5.6.3.2 for specific timing requirements).

a)Host pausing an Ultra DMA data out 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 not generating an HSTROBE edge.

Note: The device shall not immediately negate DMARQ to initiate Ultra DMA burst termination when the host stops generating HSTROBE edges. If the host does not assert STOP, in order to initiate Ultra DMA burst termination, the device shall negate DDMARDY- and wait tRP before negating DMARQ.

3)The host shall resume an Ultra DMA burst by generating an HSTROBE edge.

C141-E110-02EN

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Fujitsu MPG3XXXAT manual Data out transfer, Pausing an Ultra DMA data out burst