How to Use Olimex ESP32-EVB: Examples, Pinouts, and Specs

The Olimex ESP32-EVB is a versatile development board that harnesses the power of the ESP32 microcontroller. This board is designed for a wide range of applications, from IoT devices to complex networking projects, thanks to its built-in Wi-Fi and Bluetooth capabilities. It is an excellent choice for both hobbyists and professionals looking to develop prototypes or final products with wireless connectivity and a multitude of GPIO options.

• Internet of Things (IoT) devices
• Home automation systems
• Wireless sensor networks
• Bluetooth-enabled products
• Rapid prototyping for embedded systems

• Microcontroller: ESP32
• Operating Voltage: 3.3V
• Input Voltage: 5V via micro USB or PoE
• Digital I/O Pins: 40
• Analog Input Pins: 12 (VP, VN, 32, 33, 34, 35, 36, 39)
• Analog Output Pins: 2 (DAC1, DAC2)
• Flash Memory: 4MB
• SRAM: 520 KB
• Clock Speed: 240 MHz
• Wi-Fi: 802.11 b/g/n
• Bluetooth: v4.2 BR/EDR and BLE
• Ethernet: 100Mb interface with PoE capability

1. Powering the Board:

   • Connect a 5V power supply to the micro USB port or use the PoE feature if available.

2. Programming the Board:

   • Install the necessary drivers and the Arduino IDE or ESP-IDF.
   • Select the correct board and port in your development environment.
   • Use a micro USB cable to connect the board to your computer for programming.

3. Interfacing with External Components:

   • Use the GPIO pins to connect sensors, actuators, or other peripherals.
   • Ensure that the voltage levels are compatible with the board's 3.3V logic.

4. Wireless Connectivity:

   • Utilize the Wi-Fi and Bluetooth functionalities by including the appropriate libraries in your code.

• Always ensure that the power supply is within the specified range to prevent damage.
• When interfacing with 5V components, use level shifters to avoid damaging the 3.3V logic pins.
• Use decoupling capacitors close to the power pins to minimize noise and voltage spikes.
• Avoid drawing more than 12 mA from any GPIO pin.
• For Wi-Fi and Bluetooth applications, ensure that the antenna area is not obstructed to maintain signal integrity.

• Board Not Recognized by Computer:

  • Check the USB cable and port.
  • Ensure that the correct drivers are installed.

• Wi-Fi or Bluetooth Not Working:

  • Verify that the antenna is not obstructed.
  • Check your code for proper initialization of wireless functionalities.

• GPIO Pin Not Functioning:

  • Ensure that the pin is not being used by another peripheral (e.g., SD card or USB).
  • Check for soldering issues or shorts on the board.

• Always start with a simple blink program to ensure the board is functioning correctly.
• Use serial output to debug and track down issues in your code.
• Consult the Olimex ESP32-EVB forums and community for help with specific problems.

• Q: Can I power the board through the GPIO pins?

  • A: It is not recommended to power the board through GPIO pins. Use the designated power input methods.

• Q: How do I enable PoE on the board?

  • A: To enable PoE, you need a PoE-compliant router or injector and ensure that the board's PoE option is configured correctly.

• Q: What is the maximum range of the Wi-Fi and Bluetooth signals?

  • A: The range depends on environmental factors, but typically Wi-Fi can reach up to 50 meters indoors, and Bluetooth has a range of about 10 meters.

// Basic Wi-Fi connection example for the Olimex ESP32-EVB

#include <WiFi.h>

// Replace with your network credentials
const char* ssid = "your_SSID";
const char* password = "your_PASSWORD";

void setup() {
  Serial.begin(115200);
  
  // Connect to Wi-Fi
  WiFi.begin(ssid, password);
  
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.println("Connecting to WiFi...");
  }
  
  Serial.println("Connected to WiFi");
}

void loop() {
  // Put your main code here, to run repeatedly:
}

Remember to replace your_SSID and your_PASSWORD with your actual Wi-Fi network credentials. This code will connect your Olimex ESP32-EVB to your Wi-Fi network and print a confirmation message to the serial monitor.