Michael Rigby-Jones wrote: > I have probably missed something here, but the USART will also > generate an interrupt when it receives a character in asynchronous > mode. Yes, but that requires the clock running, so can not be used to wake the processor from sleep. Some of the newer UARTS do have a wakeup capability. ******************************************************************** 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 .