Friends: Does someone know of a PIC chip circuit that will monitor the 220 VAC mains and use them to run, but that can automatically switch to a battery power when the mains fails? I need to make an alarm for when the power fails. Thanks in advance, Miguel Reznicek mreznicek@pretensa.com -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist