The B-L475E-IOT01A is a development board manufactured by STM32, designed to simplify the development of Internet of Things (IoT) applications. It is powered by the STM32L475 microcontroller, which is optimized for low-power operation. The board integrates a wide range of sensors, connectivity options (Wi-Fi, Bluetooth, NFC), and expansion interfaces, making it a versatile platform for prototyping and deploying IoT solutions.
Feature | Specification |
---|---|
Microcontroller | STM32L475VG (ARM Cortex-M4, 80 MHz, 1 MB Flash, 128 KB RAM) |
Connectivity | Wi-Fi (ISM43362), Bluetooth Low Energy (BLE), NFC (ST25DV04K) |
Sensors | Temperature, humidity, pressure, magnetometer, gyroscope, accelerometer, |
microphone, and Time-of-Flight (ToF) distance sensor | |
Power Supply | USB (5V) or external battery (3.3V to 5V) |
Operating Voltage | 3.3V |
Expansion Interfaces | Arduino Uno V3-compatible headers, STMod+ connector |
Debugging | Integrated ST-LINK/V2-1 debugger/programmer |
Dimensions | 95 mm x 50 mm |
The B-L475E-IOT01A features Arduino Uno V3-compatible headers for easy prototyping. Below is the pinout for the Arduino header:
Pin Name | Function | Description |
---|---|---|
A0-A5 | Analog Input | 6 analog input pins for sensors or other devices |
D0-D13 | Digital I/O | 14 digital I/O pins (PWM available on some pins) |
3.3V | Power Output | 3.3V power supply for external components |
5V | Power Output | 5V power supply for external components |
GND | Ground | Common ground |
VIN | Power Input | External power input (3.3V to 5V) |
SDA/SCL | I2C Communication | I2C data and clock lines |
TX/RX | UART Communication | Serial communication pins |
Pin Name | Function | Description |
---|---|---|
1-2 | Power Supply | 3.3V and GND |
3-4 | UART | TX and RX for serial communication |
5-6 | I2C | SDA and SCL for I2C communication |
7-8 | GPIO | General-purpose input/output pins |
Powering the Board:
Connecting Sensors and Peripherals:
Programming the Board:
Using Built-in Sensors:
The following example demonstrates how to read temperature data from the onboard HTS221 sensor and print it to the serial monitor.
#include <Wire.h>
#include <HTS221Sensor.h> // Include the library for the HTS221 sensor
// Define I2C address for the HTS221 sensor
#define HTS221_I2C_ADDRESS 0x5F
// Create an instance of the HTS221 sensor
HTS221Sensor hts221(&Wire);
void setup() {
Serial.begin(9600); // Initialize serial communication
Wire.begin(); // Initialize I2C communication
// Initialize the HTS221 sensor
if (hts221.begin(HTS221_I2C_ADDRESS)) {
Serial.println("HTS221 sensor initialized successfully.");
} else {
Serial.println("Failed to initialize HTS221 sensor.");
while (1); // Halt execution if initialization fails
}
}
void loop() {
float temperature;
// Read temperature from the HTS221 sensor
if (hts221.getTemperature(&temperature)) {
Serial.print("Temperature: ");
Serial.print(temperature);
Serial.println(" °C");
} else {
Serial.println("Failed to read temperature.");
}
delay(1000); // Wait for 1 second before the next reading
}
Board Not Detected by IDE:
Sensors Not Responding:
Wi-Fi or Bluetooth Not Connecting:
High Power Consumption:
Q: Can I use the B-L475E-IOT01A with the Arduino IDE?
A: Yes, the board is compatible with the Arduino IDE. Install the STM32 core for Arduino to get started.
Q: How do I update the firmware on the board?
A: Use the STM32CubeProgrammer tool to update the firmware via the USB interface.
Q: What is the range of the onboard Wi-Fi module?
A: The range depends on environmental factors but typically covers 30-50 meters indoors.
Q: Can I power the board with a battery?
A: Yes, the board can be powered using an external battery connected to the VIN pin (3.3V to 5V).