I agree with you. For simplicity and cost, it really seems worthwhile to just use an external RTC chip. Most of them seem to be I2C, but I like SPI better (faster, simpler, etc.). There are some RTC "chips" that have the crystal and temperature compensation on board. You can really accurate that way. Harold -- FCC Rules Updated Daily at http://www.hallikainen.com - Advertising opportunities available! -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist