ESP32-C3: Pin mapping

[JanPetterMG]

🔧 ESP32-C3: Pin Tips & Gotchas

🎉 Feel free to share your insights, questions, or setups below!

💡 This thread is for beginners and experienced users alike. Whether you're figuring out your first build or have clever tricks to share, you're welcome to join in.

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⏰ RTC Pins

GPIO 0, 1, 3–5 can wake the ESP32-C3 from deep sleep. Useful for:

• Power button PIN_SW1
• Mode button PIN_SW2
• Interrupts like PIN_INT from a real-time clock

🎙️ Analog Input

GPIO 0, 1, 3, 4 are usable as analog inputs. For example:

• PIN_LDR for photocell signals
• PIN_MIC for microphone signals

⚠️ Avoid Strapping Pins

GPIO 2, 8, 9 have bootstrapping functions. Avoid connecting these to inputs that may float or pull them during boot.

📄 Reference

ESP32-C3 Datasheet (PDF)

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💬 Add your own:

• Board name
• Pinout overview
• Tips or pitfalls you encountered
• Questions or confusions you had as a beginner

Feel free to include your SPI, PWM, I2C, or other digital pin setups too—this thread is meant to cover practical pin mapping across different ESP32-C3 boards.

Let’s make this a helpful resource together!

[JanPetterMG]

Seeed Studio XIAO ESP32C3

📍 Pinout Diagram

Hardware overview

// IKEA Frekvens
#define PIN_MIC 3   // D1  U3 pin 7
#define PIN_SW1 4   // D2  SW1
#define PIN_SW2 5   // D3  SW
#define PIN_OE 6    // D4  EN
#define PIN_CS 7    // D5  LAK
#define PIN_SCLK 8  // D8  CLK
#define PIN_MOSI 10 // D10 DA

// IKEA Obegränsad
#define PIN_SW2 3   // D1  SW
#define PIN_OE 4    // D2  EN
#define PIN_CS 5    // D3  CLA
#define PIN_SCLK 8  // D8  CLK
#define PIN_MOSI 10 // D10 DI

⚡ Power Notes

• VUSB: Power input pin, supports 1.5 V to 6.0 V
• GND: Ground reference
• 3V3: Logic-level power output for peripherals (e.g. level shifters)