On 11/4/06, Jinx wrote: > Part of a project involves using the 18F4550 as a USB peripheral > to a PC. I've now been asked to provide a second USB port to > send data to a USB memory device (eg flash drive) for datalogging > > 1) is it at all possible to bit-bang USB out of other pins ? Someone has demonstrated USB device bit-banging using an AVR, but the speed is the low speed (around 1.5mbits/s) suitable for keyboard or mouse use, but not much else. Bit banging USB host at slow speed is possible, but the software to support the host side of the USB protocol is non-trivial. But like TCP/IP, I expect open source USB stacks to start moving into the microcontroller space soon enough. I doubt your USB memory stick will operate at low speed though. They typically work on 12mbits/s (full speed) or 480mbits/s (high speed). Maybe the USB on-the-go spec covers running them at low speed? At any rate, it's a lot more work than I expect you are interested in doing. -Adam - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Moving in southeast Michigan? Buy my house: http://ubasics.com/house/ Interested in electronics? Check out the projects at http://ubasics.com Building your own house? Check out http://ubasics.com/home/ -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist