CD2231 Intel Corporation, CD2231 Datasheet - Page 89

• Manufacturer Part Number: CD2231
• Description: CD2231 Intelligent Two-channel Lan And Wan Communications Controller
• Manufacturer: Intel Corporation

8.2
8.2.1
Datasheet
Register Name: CMR
Register Description: Channel Mode
Default Value: x’02
Access: Byte Read/Write
RxMode
Bit 7
Option Registers
Channel Mode Register (CMR)
Bit 7
Bit 6
Bits 5:3
Bits 2:0
TxMode
Bit 6
Intelligent Two-Channel LAN and WAN Communications Controller — CD2231
Receive Transfer mode
0 – Interrupt
1 – DMA
Transmit Transfer mode
0 – Interrupt
1 – DMA
Reserved – must be ‘0’.
Protocol mode select
If these options are changed, an initialize command must be given to the CD2231
through the Channel Command register.
Bit 5
0
chmd2
C0
0
1
0
0
0
0
1
1
1
1
Bit 4
0
Channel number
Channel 0
Channel 1
chmd1
0
0
1
1
0
0
1
1
Bit 3
0
chmd0
chmd2
Bit 2
0
1
0
1
0
1
0
1
Motorola Hex Address: x’1B
chmd1
HDLC
Reserved
Async
Reserved
Async–HDLC/PPP
SLIP
MNP4/ARAP
Reserved
Bit 1
Intel Hex Address: x’18
chmd0
Bit 0
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