Communication through MAX with serial device

[CorrAtm]

I am using a RS 232 to USB converter to communicate with a gas analyzer. I want to communicate using C-link protocol to communcate with the analyzer but I'm having trouble doing that through Labview and MAX. In the manual for the machine it says that the commands to the device have to begin with the ASCII character code for 128 plus its instrument id, which in my case is 43, meaning the command must start with ASCII character code 171. Each statement then has to end with a carriage return. I've tried multiple different ways to send these commands but in MAX I get an error about timeout for the VISA Serial Communicater and in Labview I get an error on the property node(I used the Basic Serial Write Read vi provided).

Can anyone help me on? I'm just not really sure how to send these commands properly to the analyzers.

[Dennis_Knutson]

You can use either technique below to send decimal 171.

There are thousands and thousands of posts related to RS232 communication. Searching the boards with the proper terms is almost certain to find an answer.

Also, I don't know how you can get an error with the property node. Show what you have done.

[CorrAtm]

Dennis,

I tried the method you recommended and the modified Basic Serial Write and Read to get the following code. Also I wanted to note that I don't need to just pass 171, I need to pass that followed by a command and then a carriage return. The VI I have now runs without an error but I get no response. Through other posts I've figured out that this is not necessarily a good thing. Any help on getting this to work?

As far as the property node is concerned I figured out why I was getting that error message.

[CorrAtm]

Oops. This is the code

[Dennis_Knutson · Accepted solution]

You are sending the characters 'C' and 'R'. That is not at all the same as the CR control code. You could have used the typecast to send hex 0D, you could use the CR constant on the String palette, you could set the string constant for hex display and send 0D, you could use the string constant set for '\' Codes Display and send \r.

[CorrAtm]

Figured it out. It was the carriage return.

Thanks for the help!