How to test the serial port on the CDP?

[JM K]

Hi,

I am trying to use the serial port ttyS2 on the CDP (Model:EV2) to communicate modbus with a PLC. I verified COMM parameters, cable were perfectly matched but am unable to get the communication started up. Is there any way that I can do a test on the serial port like a ‘loop back test’ to make sure that its working fine? Thank you and have a great day.

Best Regards,

JM

[Lonny Knudson]

Hi JM,

A simple method would be to disconnect your existing serial cable then short the TXD and RXD signals on the physical interface (of the CDP).

Next use a terminal program like minicom with flow control and local echo disabled. With local echo disabled you should still be able to see any transmitted characters echoed back to the terminal (if local echo is enabled you should see a double echo).

[Jesse Gilles]

You could also use a serial cable and connect it to your PC, run terminal software on both ends and send characters back and forth.

[JM K]

Dear Lonny and Jesse, thanks for the response. I tested the serial port. Works fine.

Best Regards,

JM

[Author]

Posts