Serial I/O Address And Register Function - Contec IPC Series User Manual

6. Appendix

SERIAL I/O Address and Register Function

The following table lists the I/O addresses in case of SERIAL A.
Table 6.2. I/O Port Addresses
I/O address DLAB
03F8H
0
1
03F9H 1
0
03FAH X
03FBH X
03FCH X
03FDH X
03FEH X
03FFH X
DLAB (Divisor Latch Access Bit) : The value in bit 7 of the line control register.
72
Read/Write
W Transmitter holding register
R Receive buffer register
W Divisor latch register (LSB)
W Divisor latch register (MSB)
W Interrupt enable register
R Interrupt ID register
W Line control register
W Modem control register
R Line status register
R Modem status register
R/W Scratch register
Register
THR
RBR
DLL
DLM
IER
IIR
LCR
MCR
LSR
MSR
SCR
PT-956SxX Series User's manual