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rancan's avatar
rancan
Occasional Contributor
5 years ago

Serial Port Communication

Hi,   I am trying to create a connection with port com, and I am using JavaScript. The goal is to send the HEX sequence and read the HEX back from the port.  I copied from this page https://suppo...
Scripting
  • AlexKaras's avatar
    AlexKaras
    5 years ago

    Hi,

     

    > The goal is to send the HEX sequence

    > Port.Write("1A030688");

    The above .Write() call does not write expected hex sequence, but writes the ASCII string (with relevant hex codes), which is not correct as I think.

    Try to prefix every hex with \x prefix (like in the article you've referenced) and check if it helps. I.e.:

    Port.Write("\x1A");

    Port.Write("\x03");

    Port.Write("\x06");

    Port.Write("\x88");

     

AlexKaras's avatar
AlexKaras
Champion Level 3
5 years ago

Hi,

 

> The goal is to send the HEX sequence

> Port.Write("1A030688");

The above .Write() call does not write expected hex sequence, but writes the ASCII string (with relevant hex codes), which is not correct as I think.

Try to prefix every hex with \x prefix (like in the article you've referenced) and check if it helps. I.e.:

Port.Write("\x1A");

Port.Write("\x03");

Port.Write("\x06");

Port.Write("\x88");

 

  • rancan's avatar
    rancan
    Occasional Contributor
    5 years ago

    Hi, 

     

    Thanks for the response. 

    I just tried to modify the Port.Write () as you mentioned, however, it still gave the blank reading of the port, or maybe is it because of the Port.BytesToRead? 

     

    Thanks in advance. 

    • AlexKaras's avatar
      AlexKaras
      Champion Level 3
      5 years ago

      Hi,

       

      > maybe is it because of the Port.BytesToRead?

      No, I don't think so...

      (Though I expect that you are sending correct sequence and that you know what your device must reply with.)

       

      I probably mentioned not correct code example from the article.

      Have you tried this (parameter's syntax might need to be adjusted):

      Port.Write(String.fromCharCode(1A));

      Port.Write(String.fromCharCode(03));

      Port.Write(String.fromCharCode(06));

      Port.Write(String.fromCharCode(88));

       

      P.S. One more think to check - is the given COM-port enabled in your system? (In BIOS, OS, etc.)

       

      • rancan's avatar
        rancan
        Occasional Contributor
        5 years ago

        Hi Alex, Thanks a lot for your help.

         

        I tried to do it in Python (not in TestComplete), as I am more comfortable using Python, by converting the hex sequence into bytes and sending it to the port (I apologise I didn't know that it has to be in bytes and I might make mistake in JavaScript). 

         

        I decided to import the external Python code into the TestComplete in JavaScript and run it with WScript.

        Thank you!