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Stealing signal

Stealing signal

Stealing signal


I have been struggling for a while now to get my webcam to work while not attached to a pc, but to a DSP. I have to do this for a project, but can't figure it out. The webcam needs some or other initialization and probably a timing signal to operate. Somehow, I have to capture the initialization procedure that the computer software uses, and simulate it on the DSP, but I have no idea how I'm gonna do that. How can I "tap" or record the signal that the PC and the webcam says to each other during initialization and operation?

The setup is: webcam connected to a USB to parallel interface IC, and onto the DSP.

I contacted Logitech, but the tech support say they are not allowed to tell me anything.

Any help appreciated!

RE: Stealing signal

I had to do this with a mouse once (I think it was Logitech too).  Although I didn't get it to work completely, I did capture the computer/mouse initialization signal.  I just wired up the computer's mouse port to a digital logic analyzer, turned on the computer, and read the signal directly.  In your case, I imagine you'd need to find/make some USB to parallel adapter that will expose each of the individual wires.  Then you can tap each of the exposed wires with a digital logic analyzer.  If you don't have a digital logic analyzer, you can maybe use a 2 oscilloscope, and measure the signal (or lack of) in all the wires individually.  Then you can chart out the combined signal on graph paper.

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