“This is wall LED clock. Despite to have only twenty LEDs it is full day clock showing time with 15 seconds precision. Is it really possible? May by these LEDs packs the time in so cryptic code that no ordinary human can read it. I believe the opposite is true: any person, who can read regular mechanical clock, can read it ( after some explanations and examples. of course). One year ago I have published project describing this approach in details: https://www.instructables.com/Half-Dial-Clock-or-Dialog-With-Know-it-all/ . But I believe examples (pictures an video here) would be sufficient enough to understand the principle.
Supplies:
- Atmega328p Microchip processor.
- Seven 10mm green LEDs, seven 10mm white LEDs, four 5mm white LEDs, one 10mm blue LED, one 10mm RGB LED. All LEDs are taken from adafruit.com.
- Twelve silicon diodes 1N4148 and one Schottky diode 1N5817
- One NTE3042 optoisolator.
- One super capacitor 0.5 Mcf 5.5 V.
- Six resistors 55 Ohm, two resistors 100 Ohm, seven resistors 150 Ohm, one resistor 170 Ohm, and one resistor 220 Ohm. All are 0.25 W.
- Crystal 32678 Htz frequency .
- Three mini pushbuttons.
- Syntax prototype board.
- 28 pin dip socket (for processor) and 6 pin dip socket (for optoisolator)
- 6 pin header (to make a connector between AVR ISP adapter and processor.
- Some wire.
- Wooden round 9x12 inches from Michael’s
- One foot / 3.4 inches wooden round from Home Depot.”