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RS-232/COM debugging


I need to use USB port for client communication and trying to use COM3 as debugging port.
I am wondering what kind of RS-232 cable I need as I don’t find pin layout of COM3 on the development board.
Is it crossover or straight?


There are two types of rs-232 pin configurations; DCE and DTE.

DCE, which means data communications equipment, is usually devices such as a modems.

DTE, which means data terminal equipment, is usually on a terminal type device. PCs, when they have a RS-232 connector, are usually DTEs.

I assume the ChixWorkX dev board is a DTE, but I am not sure. You can check the schematic to verify.

The following URL will help with determining the pin configurations of DTE and DCE.

If you connect a DCE to a DTE a straight through cable is used.

If you connect a DCE to a DCE, or a DTE to a DTE, you need a crossover cable.


Thanks Mike.
My hardware engineers are kind enough to make me both straight and crossover cable.
I am able to debug using RS-R232 by using crossover cable.

For the benefit of others who are in the same boat as I, here is what I did

In the application code I have added following

        if(Configuration.DebugInterface.GetCurrent() != Configuration.DebugInterface.Port.COM3)
        Configuration.DebugInterface.Set(Configuration.DebugInterface.Port.COM3, Configuration.DebugInterface.Port.COM3);

I have set visual studio project settings to use Serial as Transport and device as COMx.

Now I can use RS-232 for debugging the app.
By the way, My cable has just transmit, receive and ground pins connected.