Prototype: 28 hour watch

I am hoping to follow a 25 hour day for a month, and then a 28 hour day. So I am making a watch that allows you to adjust the length of day. This prototype allows you to set the length of day between 1 hour and 48 hours as well as normal functions of a watch like setting the minutes and hours.

I am using a spark fun serial 7 segment display which allows communication through soft serial or SPI. But you could use a normal 7 seg with shift registers instead.

Button 1 acts as a “Select” button, then 2nd is to set hours, 3rd to set minutes and fourth to choose day length (between 1-48hours) Short video of the button functioning:

Seven seg display, 4 buttons, 10k resistors. That is it. This is my code, it works, but I am a novice so feel free to clean it up and send it back to me! Post-it note schematic with SPI:

(MISO, RESET, RX are not used)

Next steps:

• hook it up to a pro mini
• small lithium battery
• add a tilt sensor so the display is not on all the time.
• Make/modify a small case  and attach a strap.

Advertisement