slightly hijacking this thread a little (and I apologise) but can some bright mind confirm:- I currently have a circuit which counts teeth on a gear (with a hall effect switch). If I were to add another sensor on the same gear, but half a toot= h apart, would the output from the two sensors then be grey code? and thus al= l the above apply? --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .