I'm a computer hardware engineer.I've several years experiences about interfacing IBM compqtible PCs.Usually I used serial port or parallel port to communicate with digital boards which I designed.But I decided to use USB port for this purpose.But USB is complicated.I found a really excelent book about USB.It's time to get off from old interfaces like RS_232 and use a high express train,mean USB.and one of the best choices to learn USB,cab be "USB COMPLETE",by Jan Axelson.
It's useful for both,beginners and experts,as a basic USB course or a USB indepth reference.
After reading "USB COMPLETE",I'm so brave to leave my old spool and jump into a really deep lake.
M Reza AsAdi