Countdown timer with OLED

Im hoping to make a countdown timer... with oled display, and a single button that selects 5/10/10 minutes etc, then autostarts.. making a noise at the end.

Am I being a little optimistic here ? Planning on using a nano - but not sure how accurate the timing is (doesn't need to be accurate - just repeatable.)

Advice please ?


So what is the actual question? You already know what you want. Start selecting the parts and start building :slight_smile:

Parts are on the way - just cant get my head around the timing bit...

I know in the "blink" prog, you input delays in milliseconds... but surely this is a bit clumsy when counting minutes ?