ESP32

A feature-rich, dual-core MCU equipped with Wi-Fi and dual-mode Bluetooth, ideal for IoT applications.

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ESP32 Dev Module

The ESP32 is a low-cost, low-power system on a chip (SoC) microcontroller with integrated Wi-Fi and dual-mode Bluetooth. Developed by Espressif Systems, it boasts a dual-core Tensilica Xtensa LX6 microprocessor and is highly favored by makers and engineers for building robust Internet of Things (IoT) devices.

BoardsMicrocontrollerIoTWi-Fi

Overview

Unlike standard 8-bit AVR Arduinos, the ESP32 is a 32-bit microcontroller that operates at 3.3V. It offers an incredible array of peripherals, including capacitive touch, ADCs, DACs, I2C, SPI, UART, and I2S interfaces. Its internal Wi-Fi stack allows you to connect to the internet, host web servers, or fetch APIs directly from the microcontroller.

CAUTION

3.3V Logic Level: The ESP32 is not 5V-tolerant. Applying 5V to any of its GPIO pins can instantly damage the chip. Always use logic level converters when interfacing with 5V components.

Pin Reference

The ESP32 has many pins with overlapping capabilities. Most pins can be assigned to different hardware functions via software.

Pin	Type	Description
3V3	power	Regulated 3.3V output.
VIN	power	Input voltage (typically 5V via USB or external supply).
GND	power	Ground pins.
EN	digital	Enable pin (Reset). Pulling this low resets the ESP32.
D0-D35	digital	General Purpose I/O pins (GPIO). Most support PWM.
VP / VN	analog	Analog inputs (ADC1). Often labeled GPIO36 (VP) and GPIO39 (VN). Note: Input only.
TX0 / RX0	digital	Hardware Serial 0 (used for USB programming/debugging).
TX2 / RX2	digital	Hardware Serial 2.

(Note: Pins D34, D35, VP(36), and VN(39) are input only and cannot be used as outputs or have internal pull-ups.)

Configurable Attributes

(Currently, microcontroller boards in the simulator do not have configurable graphical attributes. You upload code to them directly via the editor.)

Wiring Diagram (Blink Example)

A standard setup to blink an external LED using the ESP32.

Connect a 220-ohm resistor to pin D13.
Connect the other end of the resistor to the Anode of an LED.
Connect the Cathode of the LED to GND.

Wiring Diagram

Example Code (Wi-Fi Scan)

This example demonstrates one of the ESP32's primary features: scanning for nearby Wi-Fi networks.

cpp

#include "WiFi.h"

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

  // Set WiFi to station mode and disconnect from an AP if it was previously connected
  WiFi.mode(WIFI_STA);
  WiFi.disconnect();
  delay(100);

  Serial.println("Setup done");
}

void loop() {
  Serial.println("scan start");

  // WiFi.scanNetworks will return the number of networks found
  int n = WiFi.scanNetworks();
  Serial.println("scan done");
  
  if (n == 0) {
      Serial.println("no networks found");
  } else {
    Serial.print(n);
    Serial.println(" networks found");
    for (int i = 0; i < n; ++i) {
      // Print SSID and RSSI for each network found
      Serial.print(i + 1);
      Serial.print(": ");
      Serial.print(WiFi.SSID(i));
      Serial.print(" (");
      Serial.print(WiFi.RSSI(i));
      Serial.println(")");
      delay(10);
    }
  }
  Serial.println("");

  // Wait a bit before scanning again
  delay(5000);
}

Simulation Notes

In OpenHW Studio, ensure you select an "ESP32" board definition in the editor to use ESP32-specific libraries like WiFi.h.
The simulator provides a virtual Wi-Fi environment, allowing code like WiFi.scanNetworks() to function and return simulated access points.
Pay attention to the baud rate! The ESP32 standard debug baud rate is typically 115200, whereas standard Arduinos often default to 9600.

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ESP32 ​

Component Preview ​

Overview ​

Pin Reference ​

Configurable Attributes ​

Wiring Diagram (Blink Example) ​

Example Code (Wi-Fi Scan) ​

Simulation Notes ​