>I've set the 1ms VBtimer to switch on and off the DTR >line. With a scope, the latency measured was 55ms. Note that you will not be able to set a shorter time than 55mS with Win9x using the standard windows timer. You might be able to in WinNT which does use a finer timer I believe, but Win9x uses 55mS increments as a carry over from the DOS days. -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist