[Lazarus] Decoding USB sniff data

[Henry Vermaak]

On 4 June 2010 00:11, Mark Morgan Lloyd <markMLl.lazarus at telemetry.co.uk> wrote:
> Henry Vermaak wrote:
>
>> You can use some kind of usb snooping software to reverse engineer all
>> the transfers.  I've used this approach with success.  It's important
>> for you to familiarise yourself with the usb protocol, though.
>
> The thing one has to be careful of here is when the same pid:vid can refer
> to several different implementations. The Windows software knows how to pick
> up a private submodel number, somebody reverse-engineering the transfer
> doesn't.

I don't really know what you mean.  Do you mean that the software can
do a control transfer to query the model number, then have different
communications methods depending on that?  Either way you'll always be
able to see all the messages on the bus, so I don't see how this is a
problem.

>> Note that there aren't any fpc bindings for libusb 1 (that I know of),
>> but that should be easy to generate.
>
> http://wiki.lazarus.freepascal.org/Hardware_Access#libusb

No, these bindings are for the old (0.1) libusb.

Henry