The GGLABS T232 is very popular for debugging legacy RS-232 connections. In this article we will describe a few debugging tips and show how to emulate some of the common cable configurations.
T232 Pin assignments
|Dip Switch||DE-9 Pin||Name||Description|
|3||8||CTS||Clear to Send|
|4||7||RTS||Request to Send|
|5||6||DSR||Data Set Ready|
|6||4||DTR||Data Terminal Ready|
|7||1||DCD||Data Carrier Detect|
9-wire Straight (Default Configuration)
This is a 9-wire standard straight through cable. It's used to connect a host computer (DTE) to a modem or other device configured as a DCE.
3 wire straight configuration
Dip 1 and 2 on. No additional jumpers.
This configuration emulates a 3 wire (no hardware flow control) straight cable.
5 wire straight configuration
3 wire straight with handshake shorts
Minimal (3 wire) Null Modem
5 wire null modem
Full Null Modem
3 wire Null Modem with CTS/RTS shorts
3 wire Null Modem with full handshake shorts
5 wire null modem with shorts
3 wire loopback
5 wire loopback
DTE: Data Terminal Equipment (usually the computer)
DCE: Data Communication Equipment (traditionally a modem)