Transcend 40-Pin IDE Flash Module
128MB ~ 8GB
Host Terminating an Ultra DMA Data-In Burst
The host terminates an Ultra DMA Data-In burst by following the steps lettered below. The timing
diagram is shown in below: Ultra DMA Data-In Burst Host Termination Timing. The timing parameters
are specified in Page 12: Ultra DMA Data Burst Timing Requirements and are described in Page 13:
Ultra DMA Data Burst Timing Descriptions.
The following steps shall occur in the order they are listed unless otherwise specifically allowed:
(a) The host shall not initiate Ultra DMA data burst termination until at least one data word of an Ultra
DMA data burst has been transferred.
(b) The host shall initiate Ultra DMA data burst termination by negating -HDMARDY. The host shall
continue to negate -HDMARDY until the Ultra DMA data burst is terminated.
(c) The device shall stop generating DSTROBE edges within tRFS of the host negating -HDMARDY
(d) While operating in Ultra DMA modes 2, 1, or 0 the host shall be prepared to receive zero, one or two
additional data words after negating -HDMARDY. While operating in Ultra DMA modes 4 or 3 the
host shall be prepared to receive zero, one, two or three additional data words. The additional data
words are a result of cable round trip delay and tRFS timing for the device.
(e) The host shall assert STOP no sooner than tRP after negating -HDMARDY. The host shall not negate
STOP again until after the Ultra DMA data burst is terminated.
(f) 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 data burst is terminated.
(g) 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 data burst is terminated.
(h) The device shall release D[15:00] no later than tAZ after negating DMARQ.
(i) The host shall drive D[15:00] no sooner than tZAH after the device has negated DMARQ. For this step,
the host may first drive D[15:00] with the result of its CRC calculation (see ATA specification Ultra DMA
CRC Calculation).
(j) If the host has not placed the result of its CRC calculation on D[15:00] since first driving D[15:00]
during (9), the host shall place the result of its CRC calculation on D[15:00] (see ATA specification
Ultra DMA CRC Calculation).
(k) The host shall negate -DMACK no sooner than tMLI after the device has asserted DSTROBE and
negated DMARQ and the host has asserted STOP and negated -HDMARDY, and no sooner than tDVS
after the host places the result of its CRC calculation on D[15:00].
(l) The device shall latch the host’s CRC data from D[15:00] on the negating edge of -DMACK.
(m) 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 data burst for any one
command, at the end of the command, the device shall report the first error that occurred (see ATA
specification Ultra DMA CRC Calculation)
(n) While operating in True IDE mode, the device shall release DSTROBE within tIORDYZ after the host
negates -DMACK.
(o) The host shall neither negate STOP nor assert -HDMARDY until at least tACK after the host has
negated -DMACK.
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Transcend Information Inc.
Ver 1.7
TRANSCEND [ TRANSCEND INFORMATION. INC. ]
