Fujitsu MHM2150AT Manual/User Guide - Page 180

No data shall be transferred during this, the device has negated DMARQ.

Page 180 highlights

5.5 Ultra DMA Feature Set b) Device terminating an Ultra DMA data out burst The following steps shall occur in the order they are listed unless otherwise specifically allowed (see 5.6.4.11 and 5.6.4.2 for specific timing requirements): 1) The device shall not initiate Ultra DMA burst termination until at least one data word of an Ultra DMA burst has been transferred. 2) The device shall initiate Ultra DMA burst termination by negating DDMARDY-. 3) The host shall stop generating an HSTROBE edges within tRFS of the device negating DDMARDY-. 4) If the device negates DDMARDY- within tSR after the host has generated an HSTROBE edge, then the device shall be prepared to receive zero or one additional data words. If the device negates DDMARDY- greater than tSR after the host has generated an HSTROBE edge, then the device 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 host. 5) The device shall negate DMARQ no sooner than tRP after negating DDMARDY-. The device shall not assert DMARQ again until after the Ultra DMA burst is terminated. 6) The host shall assert STOP with tLI after the device has negated DMARQ. The host shall not negate STOP again until after the Ultra DMA burst is terminated. 7) 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 of HSTROBE. HSTROBE shall remain asserted until the Ultra DMA burst is terminated. 8) 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 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). 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 DDMARDY- within tIORDYZ after the host has negated DMACK-. C141-E104-03EN 5-103

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5.5 Ultra DMA Feature Set
C141-E104-03EN
5-103
b)
Device terminating an Ultra DMA data out burst
The following steps shall occur in the order they are listed unless otherwise
specifically allowed (see 5.6.4.11 and 5.6.4.2 for specific timing
requirements):
1)
The device shall not initiate Ultra DMA burst termination until at least
one data word of an Ultra DMA burst has been transferred.
2)
The device shall initiate Ultra DMA burst termination by negating
DDMARDY-.
3)
The host shall stop generating an HSTROBE edges within t
RFS
of the
device negating DDMARDY-.
4)
If the device negates DDMARDY- within t
SR
after the host has generated
an HSTROBE edge, then the device shall be prepared to receive zero or
one additional data words.
If the device negates DDMARDY- greater
than t
SR
after the host has generated an HSTROBE edge, then the device
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 host.
5)
The device shall negate DMARQ no sooner than t
RP
after negating
DDMARDY-.
The device shall not assert DMARQ again until after the
Ultra DMA burst is terminated.
6)
The host shall assert STOP with t
LI
after the device has negated
DMARQ.
The host shall not negate STOP again until after the Ultra
DMA burst is terminated.
7)
If HSTROBE is negated, the host shall assert HSTROBE with t
LI
after
the device has negated DMARQ.
No data shall be transferred during this
assertion.
The device shall ignore this transition of HSTROBE.
HSTROBE shall remain asserted until the Ultra DMA burst is
terminated.
8)
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 host has
asserted HSTROBE and STOP and the device has negated DMARQ and
DDMARDY-, and no sooner than t
DVS
after placing the result of its CRC
calculation on DD (15:0).
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 DDMARDY- within t
IORDYZ
after the host has
negated DMACK-.