title: Modbus sniffing using python
body: <p>I have 2 devices communicating with each other using Modbus and I would like to sniff this communication line using Python for logging purposes. I have connected my computer to the communication bus via a Modbus dongle, but I don't know how I can actually read the data. </p>
  
  <p>I have used Pymodbus before, but I don't think that would work in this case since it only allows for master or slave devices (as far as I know)</p>
  
  <p>Are there any other libraries that I can use for my purpose? Would it be possible for me to implement something like a read only socket on the COM port that doesn't interfere with existing communication on the bus? </p>
  
  <p>Thank you!</p>