10)The device shall latch the host's CRC data from DD (15:0) on the negating edge of DMACK-.

11)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).

12)The device shall release DSTROBE within tIORDYZ after the host negates DMACK-.

13)The host shall not negate STOP no assert HDMARDY- until at least tACK after negating DMACK-.

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

b)Host terminating an Ultra DMA data in burst

The following steps shall occur in the order they are listed unless otherwise specifically allowed (see 5.6.3.6 and 5.6.3.2 for specific timing requirements):

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

2)The host shall initiate Ultra DMA burst termination by negating HDMARDY-. The host shall continue to negate HDMARDY- until the Ultra DMA burst is terminated.

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 assert STOP no sooner than tRP after negating HDMARDY-. The host shall not negate STOP again until after the Ultra DMA burst is terminated.

6)The device shall negate DMARQ within tLI after the host has asserted STOP. The device shall not assert DMARQ again until after the Ultra DMA burst is terminated.

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

9)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).

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Fujitsu MPD3XXXAT manual