This software is an implementation of the serial sniffing tool jpnevulator in Python. It aims to emulate the command line interface and the output of the original tool as much as possible:

$ jpnevulator.py --ascii --timing-print \
  --tty /dev/ttyS0:SB9600d \
  --tty "/dev/ttyUSB0:Motorola MTM800" \
  --read
2015-08-30 13:23:49.461075: SB9600d
00 00 05 3B 0D 00 00 05                         ...;....
2015-08-30 13:23:49.461113: Motorola MTM800
00 05 3B 0D 00 00 05 3B 0D                      ..;....;.
2015-08-30 13:23:49.473074: SB9600d
3B 0D 00 00 05 3B 0D                            ;....;.
2015-08-30 13:23:49.473105: Motorola MTM800
00 12 05 06 39 00 12 05 06 39 1F 00 22 80 00 0E ....9....9.."...
$ 

Not all command line parameters and their functionality are implemented so far, but the most important ones are:

• --read
• --tty NAME:ALIAS
• --timing-delta MICROSECONDS
• --timing-print
• --ascii
• --width WIDTH

One feature that is available in this Python implementation (and missing in the original tool) is controling the baudrates. This is supported by adding them to the tty device name separated by an @:

jpnevulator.py --ascii --timing-print \
  --tty /dev/ttyUSB0@9600:SENDING \
  --tty /dev/ttyUSB1@9600:RECEIVING \
  --read

Alternatively, you could also set the baudrate for all of them with the argument --baudrate BAUDRATE.

The following features were decided to be left out:

• The --alias-separator parameter will not be implemented. Getting this to work with Python's ArgumentParser would be too complicated and doesn't seem to be worth the effort.

I had problems getting the original jpnevulator to work on Mac OS X. Thus, I wrote this platform independent replacement: Python and the PySerial package this software depends on are availabe for all major operating systems.

• Philipp Klaus
  [email protected]