• Minimal jumper wires, 4 on a mini breadboard
  • Personalization via LED placements and leg lengths
  • Battery operated from 3V
  • Use of 32Khz clock crystal to keep time, power-down sleep mode (LPM3) takes less than 1uA power
in sleep mode

Parts list

  • 170 tie point mini breadboard
  • MSP430G2412 (or other G/F series dip 20 pin devices w/ 4k flash)
  • Lots of LEDs (1 blue, 9 green, 6 yellow, 9 red)
  • Tactile button
  • 32Khz clock crystal
  • CR2032 button cell holder (battery not included)

Application Notes

  • Single button press shows time for a few seconds, TCG returns to sleep after that
  • Long press setup time, starting with the hours, related LEDs starts to blink
  • Short press advance the hour value. Another Long press confirms the entry
  • The tenths of the minutes and the minutes are subsequently entered like the hour
  • Once the hours and minutes (tenths and singles) have been entered, TCG returns to show mode

Breadboard Layout

layout of wires



  • Follow breadboard layout and place jumper wire on mini breadboard
  • Place MSP430G2412 on breadboard
  • Place Tactile Button
  • Cut your LEDs into different lengths, *be sure to maintain one leg longer
  • Place LEDs in groups of (1..9), opposing pairs on the same pin can be swapped for effect. Ex at b0-b1 #3 and #8 can be swapped. The "+>" is the blue LED indicating 10+ hours
  • Place Battery Holder

Source code

Source code usually resides on my github repository. https://github.com/simpleavr?tab=repositories
source code not yet available. needs cleaning up.