upm  1.1.0
Sensor/Actuator repository for libmraa (v1.5.1)
 All Data Structures Namespaces Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
Public Member Functions | Protected Attributes
Hmc5883l Class Reference
libupm-hmc5883l

API for the HMC5883L 3-Axis Digital Compass. More...

Detailed Description

Honeywell HMC5883L is a 3-axis digital compass. Communication with HMC5883L is simple and all done through an I2C interface. Different breakout boards are available. Typically, a 3V supply is all that is needed to power the sensor.

hmc5883l.jpeg
// Instantiate on I2C
upm::Hmc5883l* compass = new upm::Hmc5883l(0);
compass->set_declination(0.2749); // Set your declination from
// true north in radians
// Print out the coordinates, heading, and direction every second
while(true){
compass->update(); // Update the coordinates
const int16_t *pos = compass->coordinates();
fprintf(stdout, "coor: %5d %5d %5d ", pos[0], pos[1], pos[2]);
fprintf(stdout, "heading: %5.2f direction: %3.2f\n",
compass->heading(), compass->direction());
sleep(1);
}

Public Member Functions

 Hmc5883l (int bus)
 
float direction ()
 
float heading ()
 
const int16_t * coordinates ()
 
upm_result_t update ()
 
void set_declination (float dec)
 
float get_declination ()
 

Protected Attributes

hmc5883l_context m_hmc5883l
 

Constructor & Destructor Documentation

Hmc5883l ( int  bus)

Creates an Hmc5883l object. The I2C address cannot be changed, and is always 0x1e (7-bit).

Parameters
busI2C bus number

Member Function Documentation

const int16_t * coordinates ( void  )

Returns a pointer to an int[3] that contains the coordinates as ints

Returns
*int to an int[3]

Here is the call graph for this function:

upm_result_t update ( void  )

Updates the values by reading from I2C

Returns
0 if successful

Here is the call graph for this function:

void set_declination ( float  dec)

Sets the magnetic declination for better calibration

Here is the call graph for this function:

float get_declination ( )

Gets the current magnetic declination value

Returns
Magnetic declination as a floating-point value

Here is the call graph for this function:

Collaboration diagram for Hmc5883l:
Collaboration graph
[legend]
The documentation for this class was generated from the following files:
Generated on Wed Feb 15 2017 10:15:12 for upm by   doxygen 1.8.6