Specifications

EPC-5A Hardware & Software Reference Manual
AA
Page A-4
Coprocessor Interface:
On the EPC-5A, 486’s built-in coprocessor replaces the 80287 of PC/AT
I/O Addr Functional group Usage
0F0 Coprocessor Clear coprocessor busy
0F1 Reset coprocessor
Serial I/O (ComB) Port:
TI 16C452 emulates PC/AT chipset
I/O Addr Functional group Usage
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
Parallel I/O (LPT1) Port:
TI 16C452 emulates PC/AT chipset
I/O Addr Functional group Usage
378 LPT1 parallel port Printer data register
379 Printer status register
37A Printer control register
Serial I/O (ComA) Port:
TI 16C452 emulates PC/AT chipset
I/O Addr Functional group Usage
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
3FC Modem control register
3FD Line status register
3FE Modem status register