I found the project idea in Makezine: https://makezine.com/projects/make-29/beating-hear...
It is a wearable device with LED heart that flashes to the beating of your heart ❤
Step 1: Materials and Tools
- Arduino LilyPad
- Pulse Sensor Arduino
- 8x8 LED Matrix with MAX7219
- Li-Pol battery 25*23*23mm 3.7V 110 mAh
- TP4056 Battery Charger
- Ear clip
- Some wires
- Needle and thread
- Soldering iron
Step 2: Make Ear Clip
I used plastic clip for headphones and drill some holes for sensor and wires. Finaly i fixed it all together by epoxy glue
Step 3: LED Matrix to Arduino
I use the Arduino code from this tutorial
The wiring (u can use anothes pins):
- MAX7219 VCC pin > Arduino 5V pin
- MAX7219 GND pin > Arduino GND pin
- MAX7219 DIN pin > Arduino pin 3
- MAX7219 CS pin > Arduino pin 5
- MAX7219 CLOCK pin > Arduino pin 6
I use this Arduino sketch for test my Led. It is not using any library so this is also good to understand how to directly drive the MAX7219 chip through registers.
Step 4: Test Circuit and Code
Step 5: Install the Battery
Connect battery with charger
Step 6: Sew and Connect All Parts
Sew the band. You also can use conductive thread for connecting arduino,sensor, led matrix and battery. I used wires cause i have not any conductive thread.
Step 7: Done
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