Documentation

// ESP32-C3 - Connect to Wi-Fi and print IP
// Install: Boards Manager -> "esp32" by Espressif Systems
// Select Board: "ESP32C3 Dev Module"

#include <WiFi.h>

const char* ssid     = "YOUR_SSID";
const char* password = "YOUR_PASSWORD";

void setup() {
  Serial.begin(115200);
  delay(1000);

  Serial.print("Connecting to ");
  Serial.println(ssid);

  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }

  Serial.println();
  Serial.print("Connected! IP address: ");
  Serial.println(WiFi.localIP());
  Serial.print("RSSI: ");
  Serial.print(WiFi.RSSI());
  Serial.println(" dBm");
}

void loop() {
  delay(10000);
  Serial.print("Still connected? ");
  Serial.println(WiFi.status() == WL_CONNECTED ? "yes" : "no");
}

// ESP32-C3 - Read a 10k potentiometer on A0 (GPIO0)
// Wire: pot ends to 3V3 and GND, wiper to GPIO0

const int potPin = 0;  // A0 = GPIO0

void setup() {
  Serial.begin(115200);
  analogReadResolution(12);  // 0 - 4095
}

void loop() {
  int raw = analogRead(potPin);
  float voltage = raw * 3.3 / 4095.0;
  Serial.printf("Raw: %4d   Voltage: %.2f V\n", raw, voltage);
  delay(200);
}

# ESP32-C3 - Scan the I2C bus for devices (MicroPython)
# Flash MicroPython for ESP32-C3 from micropython.org

from machine import I2C, Pin
import time

i2c = I2C(0, sda=Pin(8), scl=Pin(9), freq=100_000)

while True:
    devices = i2c.scan()
    if devices:
        print("Found {} I2C device(s):".format(len(devices)))
        for addr in devices:
            print("  - 0x{:02X}".format(addr))
    else:
        print("No I2C devices found")
    time.sleep(2)

# ESP32-C3 - Minimal BLE peripheral with one read characteristic
# Discoverable as "ESP32C3-Hello"

import bluetooth
import time
from micropython import const

_FLAG_READ = const(0x0002)
_SVC_UUID  = bluetooth.UUID(0x180A)            # Device Information
_CHR_UUID  = bluetooth.UUID(0x2A29)            # Manufacturer Name

ble = bluetooth.BLE()
ble.active(True)

((handle,),) = ble.gatts_register_services(((_SVC_UUID, ((_CHR_UUID, _FLAG_READ),)),))
ble.gatts_write(handle, b"ShillehTek")

# Build advertising payload
name = b"ESP32C3-Hello"
adv = bytearray()
adv += bytes((2, 0x01, 0x06))                  # flags
adv += bytes((len(name) + 1, 0x09)) + name     # complete name

ble.gap_advertise(100_000, adv)
print("Advertising as 'ESP32C3-Hello' - connect with nRF Connect")

while True:
    time.sleep(1)