Timer showing seconds | 5 digits | Possible?????

Hi Guys, :slight_smile:

I’m totally new here.

I’m trying to build a timer which has following characteristics.

  1. Should display only seconds.
  2. Should have digital display
  3. Should be able to display 5 digits
  4. Should run backwards (ie, if I set 86400 and set it off, it must go like 86399, 86398, 86397…)
  5. Should have a portable size (a size of a pocket watch)

even if the size part is not possible, any help in terms of building it would be helpful. :slight_smile:

your every suggestions would be valuable to me. please feel free to share whats on your mind.

Thank you… :slight_smile: :slight_smile:


OK, that is certainly possible with any Arduino. Getting the size down to pocket-watch will be the hardest part but the Arduino Pro Mini is probably small enough to do it. Start with one of the bigger Arduinos, like the UNO, to test your code.

Some things to think about first:
6)How is it powered? Battery? Do you need a rechargeable battery and a charge controller inside the device?
7)Does it light up or is it an LCD like a watch? Lighting can take a lot of power from a battery so you probably only want it to light up when a button is pushed.
8)How are you going to set it? Maybe a run/set switch and some up/down buttons to input the starting time? Does it reset automatically or does it stop at zero?
9)How accurate? Does it have to be checked against a real watch or can a 1% error be tolerated?
10)What else does it do? An alarm at zero? Send an SMS message?