On 1/14/07, scott larson wrote: > I want to make a simple wristwatch binary clock using a 16F88 or > similar, and to save power I want to put the PIC to SLEEP and awake > during timer interrupts once a second to go about updating registers > and increment minutes and hours when necessary. > > I've never dealt with sleep mode or any of the Timers or Watchdog. > What would be recommended to use in this case, and why? > Reading the Mid-Range reference manual, I understand that Timer1 and > the Watchdog Timer can both run during sleep mode and wake the PIC up. > > Does one have advantages over the other? > > I plan to use the internal RC oscillator at a low speed (31.25 kHz). Recently I made a device which needed a reasonably accurate clock and minimum power consumption. I used a watch-crystal for timer1 (configured as counter), the internal oscillator for processing. So this is quite similar as your project. I used a PIC12F683. See for schematics and code of my 'orientation light': http://www.robh.nl/electro.php#led683. Regards, Rob. -- Rob Hamerling, Vianen NL (http://www.robh.nl/) -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist