Fujitsu MPG3XXXAT Manuale Utente
C141-E110-02EN
5 - 85
11) The device shall drive the first word of the data transfer onto DD (15:0). This step may occur
when the device first drives DD (15:0) in step (10).
12) To transfer the first word of data the device shall negate DSTROBE within t
FS
after the host
has negated STOP and asserted HDMARDY-. The device shall negate DSTROBE no sooner
than t
than t
DVS
after driving the first word of data onto DD (15:0).
5.5.3.2 The data in transfer
The following steps shall occur in the order they are listed unless otherwise specifically allowed
(see 5.6.3.3 and 5.6.3.2 for specific timing requirements):
(see 5.6.3.3 and 5.6.3.2 for specific timing requirements):
1) The device shall drive a data word onto DD (15:0).
2) The device shall generate a DSTROBE edge to latch the new word no sooner than t
DVS
after
changing the state of DD (15:0). The device shall generate a DSTROBE edge more
frequently than t
frequently than t
CYC
for the selected Ultra DMA Mode. The device shall not generate two
rising or two falling DSTROBE edges more frequently than 2t
CYC
for the selected Ultra DMA
mode.
3) The device shall not change the state of DD (15:0) until at least t
DVH
after generating a
DSTROBE edge to latch the data.
4) The device shall repeat steps (1), (2) and (3) until the data transfer is complete or an Ultra
DMA burst is paused, whichever occurs first.
5.5.3.3 Pausing an Ultra DMA data in burst
The following steps shall occur in the order they are listed unless otherwise specifically allowed
(see 5.6.3.4 and 5.6.3.2 for specific timing requirements).
(see 5.6.3.4 and 5.6.3.2 for specific timing requirements).
a) Device pausing an Ultra DMA data in burst
1)
The device shall not pause an Ultra DMA burst until at least one data word of an Ultra
DMA burst has been transferred.
DMA burst has been transferred.
2)
The device shall pause an Ultra DMA burst by not generating DSTROBE edges.
NOTE - The host shall not immediately assert STOP to initiate Ultra DMA burst
termination when the device stops generating STROBE edges. If the device does not
negate DMARQ, in order to initiate ULTRA DMA burst termination, the host shall
negate HDMARDY- and wait t
termination when the device stops generating STROBE edges. If the device does not
negate DMARQ, in order to initiate ULTRA DMA burst termination, the host shall
negate HDMARDY- and wait t
RP
before asserting STOP.
3)
The device shall resume an Ultra DMA burst by generating a DSTROBE edge.
b) Host pausing an Ultra DMA data in burst
1)
The host shall not pause an Ultra DMA burst until at least one data word of an Ultra
DMA burst has been transferred.
DMA burst has been transferred.
2)
The host shall pause an Ultra DMA burst by negating HDMARDY-.