CHAPTER 2 –Hardware Installations
SPI-8450-LLVA 13
2.7 Serial Port connector: CN6 /CN9
COM1(CN6) and COM2(CN9) are use in the 10-pins box-headers, are onboard serial
ports of the CPU card SPI-8450-LLVA. The following table shows the pin assignments of
these connectors.
CN6,CN9 PIN No. RS-232C RS-422* RS-485*
1DCD TX- TX-
2RXD TX+ TX+
3TSD RX+ RX+
4DTR RX- RX-
5GND GND GND
6DST RTS- N.C
7RTS RTS+ N.C
8CTS CTS+ N.C
9RI CTS- N.C
CN6,9
1 6
5 10
10 N.C N.C N.C
* RS-422/485 assigned for COM2(CN9) connector only.
Pin assignment after conversion by attached cable (DB-9 connector)

Note:

y For RS-485, TX+(pin 2) and RX+ (pin 3) must jumper together inside the D type
connector.
y TX- (pin 1) and RX- (pin 4) is the same.