I don't know how it works for other operating systems, but with Windows (at least in the past) the device gets matched by P&P using its PID and VID to a kernel mode driver that knows how to talk to the device. The main job of the driver is to handle P&P and other aspects of the USB bus that are incidental to the higher level conceptual operation of the device. You really really don't want to deal with a USB device at the level that drivers do. Most device manufacturers wouldn't make the information available to allow you to do that in any case.

If what you will be dealing with is simply serial devices over a RS-232 to USB adapter, then your Perl code wouldn't know the difference in any case. If you are trying to develop some sort of generic test system, then you will need to write some sort of plug in code technology to handle different devices types over different interfaces.

Perl is environmentally friendly - it saves trees

In reply to Re^5: basic serial and USB access by GrandFather
in thread basic serial and USB access by apotheon

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