HMC5983 3-Axis 3DOF Compass Magnetometer Module

HMC5983 3-Axis 3DOF Compass Magnetometer Module Documentation

Overview

The HMC5983 is a 3-axis, 3 degrees of freedom (3DOF) compass magnetometer module designed to provide accurate and reliable magnetic field measurements. This module is suitable for a wide range of applications, including robotics, navigation, and IoT devices.

Technical Specifications

Operating voltage: 3.0V to 5.5V
 Communication protocol: I2C
 Measurement range: 8.1 Gauss (x, y, z axes)
 Resolution: 14 bits (0.2 mGauss/LSB)
 Sensitivity: 1300 LSB/Gauss
 Operating temperature: -40C to 85C

Pinout

The HMC5983 module has a standard 5-pin interface:

VCC: Power supply (3.0V to 5.5V)
 GND: Ground
 SCL: I2C clock line
 SDA: I2C data line
 DRDY: Data ready interrupt pin (active low)

Code Examples

### Example 1: Basic I2C Communication using Arduino

This example demonstrates how to read the magnetic field values from the HMC5983 module using an Arduino board.
```c
#include <Wire.h>

#define HMC5983_ADDRESS 0x1E // default I2C address

void setup() {
  Wire.begin();
  Serial.begin(9600);
}

void loop() {
  uint8_t xData, yData, zData;

// Read magnetic field values
  Wire.beginTransmission(HMC5983_ADDRESS);
  Wire.write(0x03); // Register address for magnetic field values
  Wire.endTransmission();
  Wire.requestFrom(HMC5983_ADDRESS, 6);

xData = Wire.read() << 8;
  xData |= Wire.read();
  yData = Wire.read() << 8;
  yData |= Wire.read();
  zData = Wire.read() << 8;
  zData |= Wire.read();

// Print magnetic field values
  Serial.print("X: ");
  Serial.print(xData, DEC);
  Serial.print(" uT, Y: ");
  Serial.print(yData, DEC);
  Serial.print(" uT, Z: ");
  Serial.print(zData, DEC);
  Serial.println(" uT");

delay(500);
}
```
### Example 2: Calculating Heading using Python and Raspberry Pi

This example demonstrates how to calculate the heading angle from the magnetic field values using a Raspberry Pi and Python.
```python
import smbus
import math

# Define I2C bus and HMC5983 address
bus = smbus.SMBus(1)
address = 0x1E

def read_mag_data():
    # Read magnetic field values
    data = bus.read_i2c_block_data(address, 0x03, 6)
    x = (data[0] << 8) | data[1]
    y = (data[2] << 8) | data[3]
    z = (data[4] << 8) | data[5]
    return x, y, z

def calculate_heading(x, y, z):
    # Calculate heading angle in radians
    heading_rad = math.atan2(y, x)
    # Convert to degrees
    heading_deg = math.degrees(heading_rad)
    return heading_deg

while True:
    x, y, z = read_mag_data()
    heading = calculate_heading(x, y, z)
    print("Heading: {:.2f} degrees".format(heading))
    time.sleep(0.5)
```
### Example 3: Using the HMC5983 with ESP32 and MicroPython

This example demonstrates how to read the magnetic field values from the HMC5983 module using an ESP32 board and MicroPython.
```python
import machine
import utime

# Define I2C pins and HMC5983 address
i2c = machine.I2C(scl=machine.Pin(22), sda=machine.Pin(21))
address = 0x1E

def read_mag_data():
    # Read magnetic field values
    data = i2c.readfrom_mem(address, 0x03, 6)
    x = (data[0] << 8) | data[1]
    y = (data[2] << 8) | data[3]
    z = (data[4] << 8) | data[5]
    return x, y, z

while True:
    x, y, z = read_mag_data()
    print("X: {}, Y: {}, Z: {}".format(x, y, z))
    utime.sleep_ms(500)
```
These code examples demonstrate the basic I2C communication and magnetic field value reading from the HMC5983 module. You can modify and extend these examples to suit your specific application requirements.