Re: Is there any way to snoop on a USB port?
On Thu, 29 Apr 2021 21:12:10 -0500
"Martin McCormick" <martin.m@suddenlink.net> wrote:
> I have a Windows box that has software on it which programs
> two-way radios and it would be nice to know what the radio and
> computer are saying to each other.
>
> After trying a Windows application that reportedly can
> capture serial port traffic, I find that it doesn't appear to
> work with usb ports and unix/linux is my preferred world anyway
> so is there any sort of hardware that would pass through a USB
> connection from the Windows box to the radio and let me siphon
> off the traffic to a linux system and log it?
>
> The Windows app I tried to use has been around for a
> decade or more and probably works well with RS-232 ports but the
> traffic I need to grab comes from a usb device that creates
> /dev/ttyACM0 if plugged in to a Linux box and comm2 on the
> Windows system
>
> When I tried it today, it did nothing but complain that
> it was not connected. It finally dawned on me that it probably
> sees no serial ports at all as it is supposed to automatically
> find and log all port I/O and this is a relatively new HP
> Pavilion desktop computer which has no native RS-232 ports or
> parallel ports on it and, even if it did, the connection from the
> radio to the usb port is a usb plug with the usb hardware in it
> and a cable that plugs in to the radio that would most likely
> not be practical to tap.
That's still probably the easiest way. The USB connection will carry a
lot of USB protocol overhead, which you won't want to wade through to
find the data being carried. And serial is fairly easy to analyse with
one of those tiny 8-bit data loggers. They were about 100GBP ten years
ago, and are now under 10GBP from China. The magic search word is
'saleae', whose software is generally used. And you can be fairly
confident that what you see is what you get, where computer software
might do some interpreting.
--
Joe
--
Joe
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