Appendix C – Pinouts
C-3
Serial Port Connectors
There are two serial ports supported on the AHIP4+ and the AHIP5+ boards.
COM1
COM1 consists of two connectors attached to one logical port. Only one connector can
be used at a time either the RS-232 port or the RS-485 port. All termination is done out-
side the unit.
RS-232
RS-485
Pin
Signal
Pin
Signal
1A
DCD1
1B
TXD-
2A
RXD1
2B
TXD+
3A
TXD1
3B
TXD TERM -
4A
DTR1
4B
TXD TERM +
5A
GND
5B
GND
6A
DSR1
6B
RXD-
7A
RTS1
7B
RXD+
8A
CTS1
8B
RXD TERM +
9A
RI1
9B
RXD TERM -
Note
“A” denotes the lower connector (RS-232) and “B” denotes the upper
connector (RS-485).
Note
For TXD termination, connect a 150
Ω
, ½ watt resistor from pin 3B to pin
4B, with pin 1B connected to pin 3B and pin 2B connected to pin 4B. For
RXD termination, connect a 150
Ω
, ½ watt resistor from pin 8B to pin 9B,
with pin 6B connected to pin 9B and pin 7B connected to pin 8B.