Interface

5.5.4.4Terminating 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 5.6.3.10 and 5.6.3.2 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 tIORDYZ after the host has negated DMACK-.

11)The host shall neither negate STOP nor negate HSTROBE until at least tACK after negating DMACK-.

12)The host shall not assert DIOW-, CS0-, CS1-, DA2, DA1, or DA0 until at least tACK after negating DMACK.

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Fujitsu MHU2100AT manual Terminating an Ultra DMA data out burst