Figure 8-17 shows the timing when the DMAC is activated by level-sensitive low
DREQ
input in
normal mode.
Figure 8-17 Timing of DMAC Activation by Low
DREQ
Level in Normal Mode
DREQ
RD
HWR
ø
LWR
,
T
2
T
1
T
2
T
1
T
2
T
d
T
1
T
2
T
1
T
2
T
1
T
2
T
1
T
2
T
1
CPU cycle
DMAC cycle
CPU cycle
Minimum 4 states
Next sampling point
Address
bus
229
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