Specifications

Chapter 4: Programming Interface
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8A Channel 7 page register
8B Channel 5 page register
8F Refresh page register
A0 Interrupt controller 2 Port 0
Port Functional group Usage
A1 Port 1
C0 DMA Channel 4 address
C2 Channel 4 count
C4 Channel 5 address
C6 Channel 5 count
C8 Channel 6 address
CA Channel 6 count
CC Channel 7 address
CE Channel 7 count
D0 Command/status
D2 DMA request
D4 Command register (R)
Single-bit DMA req mask(W)
D6 Mode
D8 Set byte pointer (R)
Clear byte pointer (W)
DA Temporary register (R)
Master clear (W)
DC Clear mode reg counter (R)
Clear all DMA req mask (W)
DE All DMA request mask
F0 Coprocessor Clear coprocessor busy
F1 Reset coprocessor
2F8 COM2 serial port Receiver/transmitter buffer
Baud rate divisor latch (LSB)
2F9 Interrupt enable register
Baud rate divisor latch (MSB)
2FA Interrupt ID register
2FB Line control register
2FC Modem control register
2FD Line status register
2FE Modem status register
378 LPT1 parallel port Printer data register
379 Printer status register
37A Printer control register
3F8 COM1 serial port Receiver/transmitter buffer
Baud rate divisor latch (LSB)
3F9 Interrupt enable register
Baud rate divisor latch (MSB)
3FA Interrupt ID register
3FB Line control register
Port Functional group Usage