Hi Alexandre,

I agree with Andy.

Use a timer and you are able to build a RTC on every 8051 derivate.

If T0 and T1 already in use for other things than generating constant timer intervals, please watch, that T0 can be splitted.

And then 3 timers are on every 8051 or 4 timers on every 8052 or 5 timers on every 8052 with PCA.

This seems always enough timers to do all what you want.


I used never a dedicated external RTC device. Why I should waste hardware for things, which can be realized fully in software ?


Peter