AMD Geode SC1201 User Manual
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AMD Geode™ SC1200/SC1201 Processor Data Book
Core Logic Module - ISA Legacy Register Space
32579B
I/O Port 0D2h
Software DMA Request Register, Channels 7:4 (W)
Note:
Channels 5, 6, and 7 are not supported.
7:3
Reserved. Must be set to 0.
2
Request Type.
0: Reset.
1: Set.
1:0
Channel Number Request Select.
00: Illegal.
01: Channel 5.
10: Channel 6.
11: Channel 7.
I/O Port 0D4h
DMA Channel Mask Register, Channels 7:4 (WO)
Note:
Channels 5, 6, and 7 are not supported.
7:3
Reserved. Must be set to 0.
2
Channel Mask.
0: Not masked.
1: Masked.
1:0
Channel Number Mask Select.
00: Channel 4.
01: Channel 5.
10: Channel 6.
11: Channel 7.
I/O Port 0D6h
DMA Channel Mode Register, Channels 7:4 (WO)
Note:
Channels 5, 6, and 7 are not supported.
7:6
Transfer Mode.
00: Demand.
01: Single.
10: Block.
11: Cascade.
5
Address Direction.
0: Increment.
1: Decrement.
4
Auto-initialize.
0: Disabled
1: Enable
3:2
Transfer Type.
00: Verify.
01: Write transfer (I/O to memory).
10: Read transfer (memory to I/O).
11: Reserved.
1:0
Channel Number Mode Select.
00: Channel 4.
01: Channel 5.
10: Channel 6.
11: Channel 7.
Channel 4 must be programmed in cascade mode. This mode is not the default.
I/O Port 0D8h
DMA Clear Byte Pointer Command, Channels 7:4 (W)
Note:
Channels 5, 6, and 7 are not supported.
I/O Port 0DAh
DMA Master Clear Command, Channels 7:4 (W)
Note:
Channels 5, 6, and 7 are not supported.
I/O Port 0DCh
DMA Clear Mask Register Command, Channels 7:4 (W)
Note:
Channels 5, 6, and 7 are not supported.
Table 6-43. DMA Channel Control Registers (Continued)
Bit
Description