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Deciphering a Serial Communications

  • Hi. I'm hoping someone can help me solve a challenging problem or direct me to somewhere that might. I purchased a LIDAR module from a company called LeddarTech. The module works and communicates over a serial link via a USB port. It employs the MODBUS protocol. I'm trying to use a utility called 'Device Monitoring Studio' to examine the interaction between an executable provided by LeddarTech and the device in the hope that I can emulate the serial interaction between their executable and the device. DMS provides the following serial dump at the onset of communications with the device, which is a query for information about the identity of the device prior to configuration and use. I know the configurable name of the device is DEFAULT NAME. I know its serial number is AH48001. And both of those are apparent in the dump. Clearly, the dump must include data transmitted both to and from the device, but it is not clear from the dump where one ends and the other starts. Perhaps there is a better serial monitoring tool for my task that can differentiate the two? Can anyone offer any advice or insight as to how to proceed? Thanks so much.

  • Lifetime Qt Champion

    @TJOnline before starting to reverse-engineer the protocol: ask the vendor company for a programming manual?

    Regarding the spy: I've tried several serial monitors, none of them reached the quality of Wireshark. And with USB-Serial, you're even more limited (you cannot intercept the serial line between PC and device).


  • @TJOnline Hi,
    A difficult case. There are software for monitoring and sniffer. I know exactly what Pro version will handle this. Alas, software is not free, but it will definitely be able to open a COM port that is already connected. And I agree with the previous speaker in USB-Serial, you're even more limited.

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