Serial Tap
The Serial Tap plugin should be used together with a Serial Tap device from Tibbo Technology Inc.
The idea is to read all the lines of an ongoing serial (RS-232/RS-422/RS-485/TTL) communications using a pair of auxillary “spy” links. A pair is needed because half of lines (TX, DTR and RTS) can only be written to — so we need yet another connection to read those, as well.
The plugin itself works as follows. You select the Serial Tap connected over a USB cable. Then you specify the the baudrate at which the communication to be sniffed works. After that hit the Capture button and you shall see all the communications (including data, control line changes and status line changes) from the DTE point of view.
Note, that you can adjust the serial parameters at any time and flip the DTE/DCE roles without re-wiring, simply by adjusting the Flip DTE/DCE setting.