Michael Rigby-Jones wrote: > On a one wire bus the so-called "strong pull-up" is only applied very > briefly prior to communicating with a peripheral. It is not a > resistive pull-up as such, since nothing is expected to pull the bus > low when it's applied. Ah. Then in that case it is appropriate to drive the bus from a high PIC output during that time. Sorry for adding confusion. ******************************************************************** Embed Inc, Littleton Massachusetts, http://www.embedinc.com/products (978) 742-9014. Gold level PIC consultants since 2000. --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .