
UM008101-0601 Direct Memory Access
WR4 sets mode to
Burst and sets DMA
to expect Port B
address
11 0 0
No
Interrup
t
Control
Byte
Follows
0
No
Upper
Address
1
Port B
Lower
Address
Follows
01C5
Port B address
(lower)
00 0 0 0 1 0 1 05
WR5 sets Ready
active High
10 0
No
Auto
Restart
0
No Wait
Status
1
RDY
Active
High
0108A
WR6 loads Port B
address and resets
block counter *
11 0 0 1 1 1 1 CF
WR0 sets Port A as
source *
00 0 0 0 1
B→A
0105
No Address or Block
Length Bytes
Transfer No
Search
WR6 loads Port A
address
and resets block
counter
11 0 0 1 1 1 1 CF
WR6 enables DMA
to start operation.
10 0 0 0 1 1 1 87
Table 16. Sample DMA Program (Continued)
D7 D5 D4 D3 D2 D1 D0 HEX
Comentários a estes Manuais