How to Use ESP32 ESPRESSIF WROVER-B: Examples, Pinouts, and Specs

The ESP32 ESPRESSIF WROVER-B, manufactured by LILYGO, is a highly versatile microcontroller designed for IoT and embedded system applications. It features a dual-core processor, integrated Wi-Fi, and Bluetooth capabilities, making it ideal for projects requiring wireless communication. With ample RAM and flash memory, the ESP32 WROVER-B is well-suited for complex applications such as smart home devices, industrial automation, and wearable technology.

• IoT devices and smart home systems
• Wireless sensor networks
• Industrial automation and control systems
• Wearable electronics
• Robotics and drones
• Real-time data monitoring and logging

The ESP32 ESPRESSIF WROVER-B is packed with advanced features and capabilities. Below are its key technical specifications:

The ESP32 WROVER-B module has a total of 38 pins. Below is a table describing the key pins:

The ESP32 WROVER-B is easy to integrate into a variety of projects. Below are the steps and best practices for using this module.

1. Power Supply: Provide a stable 3.3V power supply to the 3V3 pin. Ensure the current rating of the power source is sufficient for the module's operation.
2. Boot Mode: To upload code, connect GPIO0 to GND and reset the module. After uploading, disconnect GPIO0 from GND.
3. Connections: Use the GPIO pins for interfacing with sensors, actuators, and other peripherals. Refer to the pin configuration table for specific pin functions.
4. Programming: The ESP32 can be programmed using the Arduino IDE or the ESP-IDF framework. Install the necessary drivers and libraries before programming.

• Use level shifters if interfacing with 5V logic devices, as the ESP32 operates at 3.3V logic levels.
• Avoid powering the module directly from USB without a voltage regulator, as it may cause instability.
• Use decoupling capacitors near the power pins to reduce noise and ensure stable operation.
• Ensure proper grounding to avoid communication issues or erratic behavior.

Below is an example of how to use the ESP32 WROVER-B with the Arduino IDE to blink an LED:

// Example: Blink an LED using ESP32 WROVER-B
// Connect an LED to GPIO2 with a 220-ohm resistor

#define LED_PIN 2  // GPIO2 is connected to the LED

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
}

1. Module Not Responding:

   • Ensure the power supply is stable and provides sufficient current.
   • Check the connections, especially the EN and GND pins.
   • Verify that the correct COM port is selected in the Arduino IDE or ESP-IDF.

2. Code Upload Fails:

   • Ensure GPIO0 is connected to GND during the upload process.
   • Check the USB cable and port for proper functionality.
   • Install the correct USB-to-serial driver for your operating system.

3. Wi-Fi or Bluetooth Not Working:

   • Verify that the antenna is not obstructed or damaged.
   • Ensure the correct SSID and password are used for Wi-Fi connections.
   • Check the Bluetooth pairing process and ensure the device is discoverable.

Q: Can the ESP32 WROVER-B operate on 5V?
A: No, the ESP32 operates at 3.3V. Use a voltage regulator or level shifter for 5V systems.

Q: How do I reset the module?
A: Press the EN pin or connect it momentarily to GND to reset the module.

Q: Can I use the ESP32 with batteries?
A: Yes, you can use a 3.7V LiPo battery with a voltage regulator to provide a stable 3.3V supply.

Q: What is the maximum range of Wi-Fi?
A: The Wi-Fi range depends on environmental factors but typically extends up to 100 meters in open space.