z80189 ZiLOG Semiconductor, z80189 Datasheet - Page 119

• Manufacturer Part Number: z80189
• Description: Z80180, Z8s180, Z8l180 Mpu Operation
• Manufacturer: ZiLOG Semiconductor

104
UM005003-0703
Z8018x
Family MPU User Manual
Bits 5–3
Reserved. Must be 0.
Bits 2–0
With DIM1, bit 1 of DCNTL, these bits control which request is presented
to DMA channel 1, as described below:
DMA Operation
This section discusses the three DMA operation modes for channel 0:
•
•
•
DIM1 IAR18–16 Request Routed to DMA Channel 1
0
0
0
0
0
0
0
1
1
1
1
1
1
1
Memory to/from memory
Memory to/from I/O
Memory to/from memory mapped I/O
000
001
010
011
10X
1X0
111
000
001
010
011
10X
1X0
111
DREQ1
ASCI0 Tx
ASCI1 Tx
ext CKA0/DREQ0
Reserved
Reserved
Reserved
ext DREQ1
ASCI0 Rx
ASCI1 Rx
ext CKA0/DREQ0
Reserved
Reserved
Reserved