How to Use ESP32 (30 pin): Examples, Pinouts, and Specs

The ESP32 (30 pin) is a powerful microcontroller designed for IoT (Internet of Things) applications and embedded systems. It features built-in Wi-Fi and Bluetooth capabilities, making it an excellent choice for wireless communication projects. With its 30 GPIO pins, the ESP32 offers a wide range of input/output functions, including ADC, DAC, PWM, I2C, SPI, UART, and more. Its versatility and high performance make it a popular choice among hobbyists and professionals alike.

• IoT devices and smart home automation
• Wireless sensor networks
• Wearable technology
• Robotics and automation
• Data logging and remote monitoring
• Bluetooth-enabled devices
• Prototyping and development of embedded systems

• Microcontroller: Tensilica Xtensa LX6 dual-core processor
• Clock Speed: Up to 240 MHz
• Flash Memory: 4 MB (varies by model)
• SRAM: 520 KB
• Wi-Fi: 802.11 b/g/n
• Bluetooth: v4.2 BR/EDR and BLE
• Operating Voltage: 3.3V
• Input Voltage Range: 5V (via USB) or 7-12V (via VIN pin)
• GPIO Pins: 30 pins (multipurpose)
• ADC Channels: 18 (12-bit resolution)
• DAC Channels: 2 (8-bit resolution)
• PWM Channels: 16
• Communication Protocols: UART, SPI, I2C, I2S, CAN
• Power Consumption: Ultra-low power consumption in deep sleep mode (~10 µA)

The ESP32 (30 pin) has the following pinout:

1. Powering the ESP32:

   • Use a USB cable to power the ESP32 via the micro-USB port (5V).
   • Alternatively, supply 7-12V to the VIN pin or 3.3V to the 3V3 pin.

2. Connecting Peripherals:

   • Use the GPIO pins for connecting sensors, actuators, and other peripherals.
   • Ensure the voltage levels of connected devices are compatible with the ESP32's 3.3V logic.

3. Programming the ESP32:

   • Install the ESP32 board package in the Arduino IDE or use the ESP-IDF framework.
   • Connect the ESP32 to your computer via USB and select the appropriate COM port.

4. Uploading Code:

   • Write your code in the Arduino IDE or ESP-IDF.
   • Press the "Upload" button to flash the code to the ESP32.
   • If required, hold the BOOT button during the upload process.

The following example demonstrates how to blink an LED connected to GPIO2:

// Define the GPIO pin for the LED
#define LED_PIN 2

void setup() {
  pinMode(LED_PIN, OUTPUT); // Set GPIO2 as an output pin
}

void loop() {
  digitalWrite(LED_PIN, HIGH); // Turn the LED on
  delay(1000);                 // Wait for 1 second
  digitalWrite(LED_PIN, LOW);  // Turn the LED off
  delay(1000);                 // Wait for 1 second
}

• Always use a level shifter when interfacing 5V devices with the ESP32's 3.3V GPIO pins.
• Avoid drawing excessive current from the 3V3 pin to prevent instability.
• Use decoupling capacitors near the power pins to reduce noise.
• For battery-powered applications, utilize the ESP32's deep sleep mode to conserve power.

1. ESP32 Not Detected by Computer:

   • Ensure the USB cable is functional and supports data transfer.
   • Install the correct USB-to-serial driver for your operating system.

2. Code Upload Fails:

   • Check the selected COM port in the Arduino IDE.
   • Hold the BOOT button while uploading the code.

3. Wi-Fi Connection Issues:

   • Verify the SSID and password in your code.
   • Ensure the Wi-Fi network is within range and operational.

4. GPIO Pin Not Working:

   • Confirm the pin is not being used for another function (e.g., ADC, SPI).
   • Check for short circuits or incorrect wiring.

Q: Can the ESP32 operate on 5V logic?
A: No, the ESP32 operates on 3.3V logic. Use a level shifter for 5V devices.

Q: How do I reset the ESP32?
A: Press the EN (Enable) button to reset the ESP32.

Q: Can I use the ESP32 with a LiPo battery?
A: Yes, you can connect a LiPo battery to the VIN pin, but ensure the voltage is within the acceptable range (7-12V).

Q: What is the maximum current the GPIO pins can source/sink?
A: Each GPIO pin can source/sink up to 12 mA safely.

This concludes the documentation for the ESP32 (30 pin).