noodlesuk
Member
Hi! I have also started to mess around with arduino and I was wondering if there's a reason you don't use real time clock (RTC)?
Just to add, yes agree with zozo, it's another overhead that you have to manage with power, both processer and energy. For most simple delay projects, the internal timer suffices.
If you use an external crystal on the ATTINY microcontroller (most arduino's have these built in) rather than the internal clock, you might find it keeps time better.The moment the microcontroller gets turned on it turns on the LEDs and it starts counting down and does this with the very same milliseconds and clock speed as it would run the RTC. There would be no difference, in this case, an RTC has no added value. If there would be a 15-minute time shift in a month time then a hard reset would be enough to start over again with a fresh count. This actually will happen anyway since it runs on battery and this will need to be replaced. If my calculations are correct about every 45 days