What Russell said for starters, especially regarding the accuracy being=20 *setpoint*. Best bet: contact some people well trained in voo-doo and call back Jim=20 Williams from the next realm; this is exactly the sort of stuff he=20 excelled in. Top it off with a dash of Bob Pease while you are at it. Seriously, this is pretty tough beans. If you do it, please enlighten=20 us on results! --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .