Martin & Marc,

I just posted in the “Code Examples” area two examples of how to create easy clocks that track time in an HH:MM format. The examples do not require Real Time Clock (RTC) ICs and are based on 4MHz Crystals. They are highly accurate at < 2 sec /day error with a standard 4.000MHz crystal (with +/- 20ppm tolerance.)

Both examples use TMRO with prescalers set to 256. This method requires only about 30 lines of code to maintain accurate time.

The programs are named EZClock1.bas and EZClock2.bas. These files are mostly comment - the code is at the end.

Maybe these can help your friend -

Good Luck,
Paul Borgmeier
Salt Lake City, Utah
www.cruxanalysis.com