Step 1: Flash Firmware
Connect your CYD via USB, then click the button:
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Step 2: Wire Your PulseSensor
Connect to the CYD's P3 and CN1 connectors:
| PulseSensor Wire |
CYD Pin |
| RED (+V) |
3.3V (CN1) |
| BLACK (GND) |
GND (P3 or CN1) |
| PURPLE (Signal) |
GPIO 35 (P3) |
⚠️ Use 3.3V, not 5V!
The CYD's CN1 provides 3.3V. The signal quality is best at this voltage.
Step 3: See Your Heartbeat
Place your finger on the PulseSensor. You'll see:
- BPM — Your heart rate
- Waveform — Scrolling pulse wave
- IBI — Time between beats
- RGB LED — Flashes red with each beat