Oskar Lopez de Gamboa / HMC5883L

HMC5883 Digital compass Library

Dependents:   sensor Cansat_program Cansat_program2 compass_cal ... more

Fork of HMC5883L by Tyler Weaver

HMC5883L.cpp@5:c9ce1eeaf001, 2013-12-10 (annotated)

Committer:
xeta05
Date:
Tue Dec 10 10:58:28 2013 +0000
Revision:
5:c9ce1eeaf001
Parent:
4:bc4e1201e092 
*Corrected the XZY order instead of the previous XYZ to match the datasheet.;  *  Added Declination compensation by a define

Who changed what in which revision?

UserRevisionLine numberNew contents of line
tylerjw 0:8b84d61cee94 1 /*
tylerjw 0:8b84d61cee94 2 * @file HMC5883L.cpp
xeta05 5:c9ce1eeaf001 3 * @author Oskar Lopez de Gamboa
tylerjw 0:8b84d61cee94 4 *
tylerjw 0:8b84d61cee94 5 * @section LICENSE
tylerjw 0:8b84d61cee94 6 *
tylerjw 0:8b84d61cee94 7 * Permission is hereby granted, free of charge, to any person obtaining a copy of this software
tylerjw 0:8b84d61cee94 8 * and associated documentation files (the "Software"), to deal in the Software without restriction,
tylerjw 0:8b84d61cee94 9 * including without limitation the rights to use, copy, modify, merge, publish, distribute,
tylerjw 0:8b84d61cee94 10 * sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
tylerjw 0:8b84d61cee94 11 * furnished to do so, subject to the following conditions:
tylerjw 0:8b84d61cee94 12 *
tylerjw 0:8b84d61cee94 13 * The above copyright notice and this permission notice shall be included in all copies or
tylerjw 0:8b84d61cee94 14 * substantial portions of the Software.
tylerjw 0:8b84d61cee94 15 *
tylerjw 0:8b84d61cee94 16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
tylerjw 0:8b84d61cee94 17 * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
tylerjw 0:8b84d61cee94 18 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
tylerjw 0:8b84d61cee94 19 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
tylerjw 0:8b84d61cee94 20 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
tylerjw 0:8b84d61cee94 21 *
tylerjw 0:8b84d61cee94 22 * @section DESCRIPTION
tylerjw 0:8b84d61cee94 23 *
tylerjw 0:8b84d61cee94 24 * HMC5883L 3-Axis Digital Compas IC
xeta05 5:c9ce1eeaf001 25 * The library done by Tyler Weaver with:
tylerjw 0:8b84d61cee94 26 *
xeta05 5:c9ce1eeaf001 27 * *Corrected the XZY order instead of the previous XYZ to match the datasheet.
xeta05 5:c9ce1eeaf001 28 * *Added Declination compensation by a define
xeta05 5:c9ce1eeaf001 29 *
tylerjw 0:8b84d61cee94 30 */
tylerjw 0:8b84d61cee94 31
tylerjw 0:8b84d61cee94 32 #include "HMC5883L.h"
tylerjw 0:8b84d61cee94 33 #include <new>
tylerjw 0:8b84d61cee94 34
tylerjw 0:8b84d61cee94 35 HMC5883L::HMC5883L(PinName sda, PinName scl) : i2c_(*reinterpret_cast<I2C*>(i2cRaw))
tylerjw 0:8b84d61cee94 36 {
tylerjw 0:8b84d61cee94 37 // Placement new to avoid additional heap memory allocation.
tylerjw 0:8b84d61cee94 38 new(i2cRaw) I2C(sda, scl);
tylerjw 0:8b84d61cee94 39
tylerjw 0:8b84d61cee94 40 init();
tylerjw 0:8b84d61cee94 41 }
tylerjw 0:8b84d61cee94 42
tylerjw 0:8b84d61cee94 43 HMC5883L::~HMC5883L()
tylerjw 0:8b84d61cee94 44 {
tylerjw 0:8b84d61cee94 45 // If the I2C object is initialized in the buffer in this object, call destructor of it.
tylerjw 0:8b84d61cee94 46 if(&i2c_ == reinterpret_cast<I2C*>(&i2cRaw))
tylerjw 0:8b84d61cee94 47 reinterpret_cast<I2C*>(&i2cRaw)->~I2C();
tylerjw 0:8b84d61cee94 48 }
tylerjw 0:8b84d61cee94 49
tylerjw 0:8b84d61cee94 50 void HMC5883L::init()
tylerjw 0:8b84d61cee94 51 {
tylerjw 0:8b84d61cee94 52 // init - configure your setup here
tylerjw 0:8b84d61cee94 53 setConfigurationA(AVG8_SAMPLES | OUTPUT_RATE_15); // 8 sample average, 15Hz, normal mode
xeta05 5:c9ce1eeaf001 54 setConfigurationB(0x20); // default gain
tylerjw 0:8b84d61cee94 55 setMode(CONTINUOUS_MODE); // continuous sample mode
xeta05 5:c9ce1eeaf001 56 wait(0.006);//wait 6ms as told in the datasheet
tylerjw 0:8b84d61cee94 57 }
tylerjw 0:8b84d61cee94 58
tylerjw 0:8b84d61cee94 59 void HMC5883L::setConfigurationA(char config)
tylerjw 0:8b84d61cee94 60 {
tylerjw 0:8b84d61cee94 61 char cmd[2];
tylerjw 0:8b84d61cee94 62 cmd[0] = CONFIG_A_REG; // register a address
tylerjw 0:8b84d61cee94 63 cmd[1] = config;
tylerjw 0:8b84d61cee94 64
tylerjw 0:8b84d61cee94 65 i2c_.write(I2C_ADDRESS, cmd, 2);
tylerjw 0:8b84d61cee94 66 }
tylerjw 0:8b84d61cee94 67
tylerjw 0:8b84d61cee94 68 void HMC5883L::setConfigurationB(char config)
tylerjw 0:8b84d61cee94 69 {
tylerjw 0:8b84d61cee94 70 char cmd[2];
tylerjw 0:8b84d61cee94 71 cmd[0] = CONFIG_B_REG; // register b address
tylerjw 0:8b84d61cee94 72 cmd[1] = config;
tylerjw 0:8b84d61cee94 73
tylerjw 0:8b84d61cee94 74 i2c_.write(I2C_ADDRESS, cmd, 2);
tylerjw 0:8b84d61cee94 75 }
tylerjw 0:8b84d61cee94 76
tylerjw 0:8b84d61cee94 77 char HMC5883L::getConfigurationA()
tylerjw 0:8b84d61cee94 78 {
tylerjw 0:8b84d61cee94 79 char cmd[2];
tylerjw 0:8b84d61cee94 80 cmd[0] = CONFIG_A_REG; // register a address
tylerjw 0:8b84d61cee94 81 i2c_.write(I2C_ADDRESS, cmd, 1, true);
tylerjw 0:8b84d61cee94 82 i2c_.read(I2C_ADDRESS, &cmd[1], 1, false);
tylerjw 0:8b84d61cee94 83 return cmd[1];
tylerjw 0:8b84d61cee94 84 }
tylerjw 0:8b84d61cee94 85
tylerjw 0:8b84d61cee94 86 char HMC5883L::getConfigurationB()
tylerjw 0:8b84d61cee94 87 {
tylerjw 0:8b84d61cee94 88 char cmd[2];
tylerjw 0:8b84d61cee94 89 cmd[0] = CONFIG_A_REG; // register b address
tylerjw 0:8b84d61cee94 90 i2c_.write(I2C_ADDRESS, cmd, 1, true);
tylerjw 0:8b84d61cee94 91 i2c_.read(I2C_ADDRESS, &cmd[1], 1, false);
tylerjw 0:8b84d61cee94 92 return cmd[1];
tylerjw 0:8b84d61cee94 93 }
tylerjw 0:8b84d61cee94 94
tylerjw 0:8b84d61cee94 95 void HMC5883L::setMode(char mode = SINGLE_MODE)
tylerjw 0:8b84d61cee94 96 {
tylerjw 0:8b84d61cee94 97 char cmd[2];
tylerjw 0:8b84d61cee94 98 cmd[0] = MODE_REG; // mode register address
tylerjw 0:8b84d61cee94 99 cmd[1] = mode;
tylerjw 0:8b84d61cee94 100 i2c_.write(I2C_ADDRESS,cmd,2);
tylerjw 0:8b84d61cee94 101 }
tylerjw 0:8b84d61cee94 102
tylerjw 0:8b84d61cee94 103 char HMC5883L::getMode()
tylerjw 0:8b84d61cee94 104 {
tylerjw 0:8b84d61cee94 105 char cmd[2];
tylerjw 0:8b84d61cee94 106 cmd[0] = MODE_REG; // mode register
tylerjw 0:8b84d61cee94 107 i2c_.write(I2C_ADDRESS, cmd, 1, true);
tylerjw 0:8b84d61cee94 108 i2c_.read(I2C_ADDRESS, &cmd[1], 1, false);
tylerjw 0:8b84d61cee94 109 return cmd[1];
tylerjw 0:8b84d61cee94 110 }
tylerjw 0:8b84d61cee94 111
tylerjw 0:8b84d61cee94 112 char HMC5883L::getStatus()
tylerjw 0:8b84d61cee94 113 {
tylerjw 0:8b84d61cee94 114 char cmd[2];
tylerjw 0:8b84d61cee94 115 cmd[0] = STATUS_REG; // status register
tylerjw 0:8b84d61cee94 116 i2c_.write(I2C_ADDRESS, cmd, 1, true);
tylerjw 0:8b84d61cee94 117 i2c_.read(I2C_ADDRESS, &cmd[1], 1, false);
tylerjw 0:8b84d61cee94 118 return cmd[1];
tylerjw 0:8b84d61cee94 119 }
tylerjw 0:8b84d61cee94 120
tylerjw 3:14d274e0f9de 121 void HMC5883L::getXYZ(int16_t output[3])
tylerjw 0:8b84d61cee94 122 {
tylerjw 0:8b84d61cee94 123 char cmd[2];
tylerjw 0:8b84d61cee94 124 char data[6];
tylerjw 0:8b84d61cee94 125 cmd[0] = 0x03; // starting point for reading
tylerjw 0:8b84d61cee94 126 i2c_.write(I2C_ADDRESS, cmd, 1, true); // set the pointer to the start of x
tylerjw 0:8b84d61cee94 127 i2c_.read(I2C_ADDRESS, data, 6, false);
tylerjw 0:8b84d61cee94 128
tylerjw 0:8b84d61cee94 129 for(int i = 0; i < 3; i++) // fill the output variables
tylerjw 0:8b84d61cee94 130 output[i] = int16_t(((unsigned char)data[i*2] << 8) | (unsigned char)data[i*2+1]);
tylerjw 1:8a1357c351c6 131 }
tylerjw 1:8a1357c351c6 132
tylerjw 1:8a1357c351c6 133 double HMC5883L::getHeadingXY()
tylerjw 1:8a1357c351c6 134 {
tylerjw 4:bc4e1201e092 135 int16_t raw_data[3];
tylerjw 1:8a1357c351c6 136 getXYZ(raw_data);
xeta05 5:c9ce1eeaf001 137 //The HMC5883L gives X Z Y order
xeta05 5:c9ce1eeaf001 138 double heading = atan2(static_cast<double>(raw_data[2]), static_cast<double>(raw_data[0])); // heading = arctan(Y/X)
tylerjw 1:8a1357c351c6 139
xeta05 5:c9ce1eeaf001 140
xeta05 5:c9ce1eeaf001 141 heading += DECLINATION_ANGLE;
tylerjw 1:8a1357c351c6 142
tylerjw 1:8a1357c351c6 143 if(heading < 0.0) // fix sign
tylerjw 2:8eb755577f83 144 heading += PI2;
tylerjw 1:8a1357c351c6 145
tylerjw 2:8eb755577f83 146 if(heading > PI2) // fix overflow
tylerjw 2:8eb755577f83 147 heading -= PI2;
tylerjw 1:8a1357c351c6 148
tylerjw 1:8a1357c351c6 149 return heading;
tylerjw 0:8b84d61cee94 150 }