Specifications

Chipset and I/O Map
EPC-100 Hardware Reference A-8
Serial I/O (COM A) Port
I/O
Addr
Functional group Usage
3F8 COM A 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
3FC Modem control register
3FD Line status register
3FE Modem status register
Interrupt Control Registers
4D0 Interrupt PIIX3 Edge/ level control - Int1
4D1 PIIX3 Edge/ level control - Int2
ECP Registers
778 ECP Data FIFO/ Config Register A
779 Data FIFO/ Config Register B
77A Extended Control Register
Watchdog Control and System Slot ID
8150 Watchdog Control and
System Slot ID
Bit Usage
0 WDTV - Watchdog Timer Value
1 WDTV
2 WDIE - Watchdog Timer Interrupt
Event
3 WDEV - Watchdog Event
4 ENEV - ENUM# Event
5 ENIE - ENUM# Interrupt Event
6 Reserved
7 Reserved