I cant help with the original post but I am working an what I think is an application that incorporates RTC. What i have been curious about is a definition of RTC. The app I have updates a 32 bit seconds counter via timer interrupt and the seconds counter is synced every 24 hours to a local NTP server. The civil time (GMT or WST) is then calculated every time it is needed ie when the time display is updated (every second). So I dont keep track of min,hour, day, month, year so to speak but I do keep track of the secs since the epoch. Is this considered an RTC. It also forgets the time when the power is lost (something I want to fix) and needs to resync to NTP. I cant decided if it is best to simply track the secs and calculate civil time every display update, or track civil time and update the 32 bit secs counter every 24 hours and then sync civil time from this. Is there a standard approach here. All suggestions comment welcome. Cheers Justin 2009/6/24 Alan B. Pearce > You may want to look at http://www.qwikandlow.com/ where the author > discusses using a pair of 18LF series devices. In the downloadable book he > appears to use a 32kHz crystal for a clock using the standard timers. > > -- > http://www.piclist.com PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist