Specifications

EPC-33/34 Hardware Reference
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I/O Address Maps
The following defines the I/O addresses decoded by the EPC-33/34.
Chipset Registers:
PicoPower PC/AT 1 and 2 chips
I/O Addr Functional group Usage
024 Chipset Programming Index Register
026 Data Register
061 Port B Misc. functions
070 Port 70 Real time clock
092 Port 92 Misc. functions
Keyboard Controller:
S82C42PE chip
060 Keyboard Data port
064 Command/status port
Ethernet Port:
AT/LANTIC chip
I/O Addr Functional group Usage
280-28F Ethernet Various
Serial I/O (COM1:) Port:
SMC 37C665 emulates 8250 of PC/AT
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