How to load digital signals from a USB port into memory?

Question

My friend is working on a project in which he needs to get some digital signals into a computer to display/manipulate them.

So I advised him to insert those signals into a USB port due to it's popularity (because the device (which outputs the signals) and the program used for display and manipulation should both be designed for real world usage and might be sold in the market)

The targeted platform is Windows primarily but it would be better if the software was cross-platform. And my friend has knowledge in C++, and wouldn't mind learning C as well.

Where should he start, and what are the steps to get the signals into memory?

Many Thanks

Answer 1

There is a great article here: USB hardware/software integration that describes the process in full.

Answer 2

Get a Labjack or one of the Phidgets. (I've used the former several times, not the latter) They're fairly inexpensive and both have Java driver support, among other things. (like LabView drivers)

Answer 3

There are more ports on computers, and many ports are easier than USB. USB supports 127 devices, and therefore devices have to cooperate. On the other hand, a microphone input is meant for exactly one input. You can sample it at 8 bit/22Khz or better, and typically you get HW buffering. You can also use existing drivers, and simple APIs.