I would like to make a timer.
The timer will have a 7 segment digital display and will work with a microcontroller of some sort.
I would like to be able to put in a time (e.g. anywhere between 0 - 10 minutes) and have it countdown from the input time to zero. I would like to display down to the millisecond resolution as well, but this is not crucial.
I want the timer to be relatively accurate (up to +- 1 second in ~20 minutes).
What kind of circuitry do I need? Will a 555 timer circuit be able to handle this? Need some direction to get started! Please let me know what other information is required! Thank you.
So I got:
- HS420361K-32 x2
- MAX7219 backing thingy
- 16-Key Keypad
I am assuming all of this will work together well. Am I missing anything here?
I will be fiddling with the Arduino software for a while until I figure out how I can/want to do this.
Any tips would be most welcome =)