Re: Reading real-time USB data

I read "live" data from an Arduino attached to the USB port in Perl. You can see how I did it at http://www.martin-evans.me.uk/node/86. Basically I just use Win32::SerialPort. I'm sure you can do something similar in other operating systems.

Comment on Re: Reading real-time USB data

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Re^2: Reading real-time USB data by locked_user sundialsvc4 (Abbot) on Apr 12, 2011 at 20:31 UTC
It sounds to me like the requirement here is to intercept the USB data, Wireshark-style, so that the data is being read by the Perl program while it is also being read by the proprietary software. I think that it is safe to say that some “OS-specific privileged-mode high magick” will be required in order to do that. Or maybe just a piece of wire. If the data is simply coming in as a serial data stream, and it is now being sent using USB just because those connectors require a lot fewer wires (i.e. no command-and-control data going the other way), then perhaps you could electrically split the wire using some kind of a pigtail without running into impedance or voltage-drop problems.

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Re^2: Reading real-time USB data
by locked_user sundialsvc4 (Abbot) on Apr 12, 2011 at 20:31 UTC

It sounds to me like the requirement here is to intercept the USB data, Wireshark-style, so that the data is being read by the Perl program while it is also being read by the proprietary software.

I think that it is safe to say that some “OS-specific privileged-mode high magick” will be required in order to do that. Or maybe just a piece of wire. If the data is simply coming in as a serial data stream, and it is now being sent using USB just because those connectors require a lot fewer wires (i.e. no command-and-control data going the other way), then perhaps you could electrically split the wire using some kind of a pigtail without running into impedance or voltage-drop problems.