I've just stumbled upon an old, experimental plug-in dissector that I wrote to dissect "raw" AT/Hayes commands in USB traces, during the process of working on another, otherwise unrelated dissector. (See https://bitbucket.org/vmlemon/usb_isi_dissector_for_wireshark/src/eec3bf16fedf/at-hayes/ for the source).

It's very rough; and I don't know what the best way to deal with displaying and manipulating strings of an unknown length is - although it nicely filled a need that I had at the time (identifying AT commands traffic amongst a proprietary protocol and other "line noise", in order to filter them out).

If there's any interest, I'd be willing to try and clean it up for potential submission into mainline Wireshark. 

Tyson.

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