Thomas Schattat
Published

Yet another dot matrix clock

NTP synchronized dot matrix clock showing temperatures and humidity.. Optionally the time source can be GPS.

AdvancedFull instructions provided20 hours2,283
Yet another dot matrix clock

Things used in this project

Hardware components

DS18B20 Programmable Resolution 1-Wire Digital Thermometer
Maxim Integrated DS18B20 Programmable Resolution 1-Wire Digital Thermometer
×2
DHT22 Temperature Sensor
DHT22 Temperature Sensor
×1
Max7219 Quad module
×8
SparkFun Solder-able Breadboard
SparkFun Solder-able Breadboard
×1
Buck converter 3A
×1
ESP32 development board
×1
7408
×1

Software apps and online services

PlatformIO IDE
PlatformIO IDE
VS Code
Microsoft VS Code

Story

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Custom parts and enclosures

Gerber files of my PCBs

PCB for 7 LED blocks with Max7219, you need 4 pieces and will join them together if you decide not to use OTS modules

Schematics

ESP circuit

Power supply to ESP32 module, display driver 7408, temperature sensors and DHT22

LED display

How to daisy-chain the modules and to connect them to the CPU circuit

My home designed stripes with 7 Max7219 blocks

My circuit boards. I combined 4 of those in my clock

Max7219 and the matrix

Here you can see how the Max and the LED blocks are connected.

DS18B20 wiring

How to connect the temperature sensors in one-wire parasite power mode

Code

Source files for VS Code PlatformIO

C/C++
CPP source file and header files
No preview (download only).

Credits

Thomas Schattat

Thomas Schattat

1 project • 0 followers

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