hey there,

i still have problems with my RTC (the PCF 8583)
the RTC works fine when nothing happens. the time and date or shown properly.

but i want to make it possible to change the time and date in my program. to do this i want to use a PC keyboard. when i use the "left" and "right" arrows, the time or date blinks (the sec, min, hour, day, month and year). to change the value of the time/date i want to use the "up" or "down" arrows. there are no problems with selecting the time or date with the left or right arrows. but when i want to change te value of the date (the time works fine).

the days only counts to 10 and then jumps back to 0. when counting down (below 0) then my program doesn't respond anymore.

the same problem is the month. and i don't what exaclty happens to the year when i want to change is. when changing the year gets every time another value (the value is irregular).

does anyone know how to solve this problem. i have already the datasheets and app notes. in the app notes are some fauts. an example of one of these faults is that they say that the binairy value 0001 0101 is the same as the hex value 16.

thanks in advance.