At 01:59 PM 2/10/02 -0800, rad0 wrote: >let me give this a try - thanks If you have a pair of output pins, you can do a bridge drive, but be careful. You want to take both pins to the same state, before taking them to opposite states. 00,01,11,10,00... rather than 10,01,10... The reason is that with the second sequence, you make a capacitive voltage doubler, and are sinking large current pulses into the protection diodes, risking CMOS latchup. -- Dave's Engineering Page: http://www.dvanhorn.org Got a need to read Bar codes? http://www.barcodechip.com Bi-directional read of UPC-A, UPC-E, EAN-8, EAN-13, JAN, and Bookland, with two or five digit supplemental codes, in an 8 pin chip, with NO external parts. -- http://www.piclist.com hint: To leave the PICList mailto:piclist-unsubscribe-request@mitvma.mit.edu