Arduino LED Matrix Clock

thingiverse

This is a simple Desk Clock made from five 8x8 LED matrices and an Arduino Nano / Pro Mini This clock uses a DS3231 RTC IC, which is not only quite accurate, but does also provide a temperature reading (which isn't as accurate but good enough). In order to switch between the normal Time-Display to the Date / Temperature Reading, a touch sensor (TTP223) or button can be used. The matrices (with MAX7219 driver), RTC and touch sensor can all be bought via e-Bay or Aliexpress. Unfortunately the LEDs and / or their driver chip becomes quite warm which is obliviously a problem when trying to acquire an accurate temperature reading of the environment. Therefore I decided to use a DHT11 sensor which is placed further away, on the end of the power cable. One of the former data lines in an old USB cable can be used to communicate with the sensor. Since I²C uses two wires for communication, it would be possible to place the RTC on the end of the cable too. I decided to use the heat-spreader of an old Intel Pentium 4 as the touch button on the top. This large chunk of metal does increase the trigger-distance quite significantly, which made it impossible for me to mount the clock on the wall. The sensitivity of the touch-sensor can be tweaked! (See last image) In addition to the 3D-printable model I have provided the necessary Arduino-Code here: https://github.com/wilhelmzeuschner/arduino_led_matrix_clock <h3>If you build this project and want to give me something back in return, I'd be extremely happy to see a post under "Makes"! :)</h3>