- OMEGA High Speed 8-Channel Thermocouple Interface Card User Guide

TCIC User’s Manual

6. USB, RS232 & RS485

In addition to USB, The TCIC has an option for both full-duplex

RS232 and half-duplex RS485 interfaces. These are brought out on

CONN6, a 9 way ‘D’ type connector. The pin-out is as follows:

CONN6 PIN FUNCTION

1 RS485-

2 RS232 TX (out of TCIC)

3 RS232 RX (into TCIC)

4 NC

5 SIGNAL GROUND

6 RS485+

7 NC

8 NC

9 NC

I.e., for RS232 use pins 2,3 & 5 and for RS485 use pins 1,5 & 6

For RS232 connection, a standard direct (straight through) wired 9D

M-F cable can be used for direct connection to a standard 9 way ‘D’

type PC COM port.

RS485 line termination – placing a jumper across the two leftmost

pins of LK2 puts a 120 Ohm (ac coupled) impedance across the

RS485 data lines. This should be used in single TCIC RS485

applications. In applications where multiple TCIC boards reside on

one RS485 bus, the termination impedance should only be added

on the last board on the bus.

COMMUNICATION PARAMETERS

For both the full-duplex RS232 and half-duplex RS485 interfaces the

communications parameters are fixed as follows:

Baud Rate 115,200 baud

Data 8 bits

Parity None

Stop Bits 1

► This is generally referred to as “8,N,1”.