2 the data in transfer, 3 pausing an ultra dma data in burst – FUJITSU MPC3065AH User Manual

Page 136

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C141-E056-01EN

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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

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 5.6.4.3 and 5.6.4.2):

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 no
more 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 5.6.4.4 and 5.6.4.2 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.

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

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.

2)

The host shall pause an Ultra DMA burst by negating HDMARDY-.

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