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Thread: RS-232 and RS-422

  1. #1
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    Default RS-232 and RS-422

    Hi,

    I have a simple Qt code which sends a string to the COM port. The code is working with RS-232 but fails for RS-422. Do I have to make any other settings to make it work for RS-422? Or the same code should be fine for both?

    Thanks

  2. #2
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    Default Re: RS-232 and RS-422

    Hi.

    It depends from your RS422 device. Because some the cheap converters is used the additional manual switching of stream direction.

    E.g. the RTS pin and so on. E.g. you should set the pin state to Hi before writing, and reset to low before reading..

    But if your RS422 device supports by hardware the automatic mode of switching of the direction - that problems shan't be.

  3. #3
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    Default Re: RS-232 and RS-422

    Hi,
    Through hyperterminal the sending is fine.

  4. #4
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    Default Re: RS-232 and RS-422

    Do you use synchronous or asynchronous mode? i.e. do you use any handshaking lines or flow control? or do you use only the data lines without hardware or software flow control?

  5. #5
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    Default Re: RS-232 and RS-422

    Hello guys I have the exact same issue. Did anyone find any solution for this ?

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