jim@jpes.com wrote: > You should still add delays in the routine where you are changing the > state of PORTB. A NOP between them should be enough to see if RMW is > a problem. No, this is incorrect advice. Read-modify-write is not a issue here. ******************************************************************** 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 .