Fujitsu MPD3043AT, Руководство по эксплуатации продукта

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C141-E069-02EN 5 - 77
3) The device shall stop generating DSTROBE edges within t
RFS
of the host negating
HDMARDY-.
4) If the host negates HDMARDY- within t
SR
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 t
SR
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 t
RFS
timing for the device.
5) The host shall resume an Ultra DMA burst by asserting HDMARDY-.
5.5.3.4 Terminating 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 t
SS
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 t
AZ
after negating DMARQ.
4) The host shall assert STOP within t
LI
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 t
LI
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.
6) The host shall drive DD (15:0) no sooner than t
ZAH
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):
7) If DSTROBE is negated, the device shall assert DSTROBE within t
LI
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) If the host has not placed the result of its CRC calculation on DD (15:0) since first
driving DD (15:0) during (6), the host shall place the result of its CRC calculation on
DD (15:0) (see 5.5.5).
9) The host shall negate DMACK- no sooner than t
MLI
after the device has asserted
DSTROBE and negated DMARQ and the host has asserted STOP and negated
HDMARDY-, and no sooner than t
DVS
after the host places the result of its CRC
calculation on DD (15:0).