Unique software for unique users


ttyUSBSpy is a serial port spy, it works on usb-serial converters. It relays on the usbmon module functionality. tcpdump captures data betwen the PC and the usb conversor chip, ttyUSBSpy filters the captured data and show the data and signals of Rs232 port. The GUI Shows the data in Hex Mode.


extract the archive and run

python DlgttyUsbSpy.py

to activate capture mode

sudo python DlgttyUsbSpy.py


as a practical approach, you would probably:

  1. Capture data:
    • with capture mode
    • using the wireshark and capturing the usb data
    • using tcpdump
    • tcpdump -i usbmon1 -w usblog.pcap
      usbmon1 is the usbmon module asociated with the USB-RS232 conversor.
      usblog.pcap is the file to store the captured data.
  2. Charge captured file
  3. ttyUSBSpy decodes the file and shows data and signals.
  4. Analise the captured file
    • Colors
    • Send bytes or signals are shown in blue
      Received bytes or signals are shown in green
      Selected bytes or signals are shown in red
    • If we have "|" simbol instead of and HEX code, it is a signal change (RTS, CTS or DTR signal has changed), left-clinking in that symbol Modem Line Status shows the result.
      • RTS(xx xx xxxxx)means that RTS signal has been activated.
      • CTS RTS(xxxx xxxxx)means that RTS and CTS signal has been activated
      • (xx xx xxxxx)means that no signal is activated, so if before that moment CTS was activated them it has been deactivated.
    • If we have a HEX code (0x58 for example) left-clicking activates T1, t1 shows the unix time where this hex code was trasmitted.
      If we right-click in other HEX code, then activates T2, t2 shows unix time that this code was transmitted. And Delta shows the t2-t1 time, this is usefull to know the time betwen to transmitted code or signals.
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