The library for the HMC5883L, which allows you to receive directional information from this library.
Dependents: Seeed_Grove_Digital_Compass_Example
Fork of HMC5883L by
HMC5883L.h
- Committer:
- tylerjw
- Date:
- 2012-11-06
- Revision:
- 3:14d274e0f9de
- Parent:
- 2:8eb755577f83
File content as of revision 3:14d274e0f9de:
/* * @file HMC5883L.h * @author Tyler Weaver * * @section LICENSE * * Permission is hereby granted, free of charge, to any person obtaining a copy of this software * and associated documentation files (the "Software"), to deal in the Software without restriction, * including without limitation the rights to use, copy, modify, merge, publish, distribute, * sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in all copies or * substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. * * @section DESCRIPTION * * HMC5883L 3-Axis Digital Compas IC * For use with the Sparkfun 9 Degrees of Freedom - Sensor Stick * * Datasheet: * * http://dlnmh9ip6v2uc.cloudfront.net/datasheets/Sensors/Magneto/HMC5883L-FDS.pdf */ #ifndef HMC5883L_H #define HMC5883L_H #include "mbed.h" /* * Defines */ //----------- // Registers //----------- #define CONFIG_A_REG 0x00 #define CONFIG_B_REG 0x01 #define MODE_REG 0x02 #define OUTPUT_REG 0x03 #define STATUS_REG 0x09 // configuration register a #define AVG1_SAMPLES 0x00 #define AVG2_SAMPLES 0x20 #define AVG4_SAMPLES 0x80 #define AVG8_SAMPLES 0xC0 #define OUTPUT_RATE_0_75 0x00 #define OUTPUT_RATE_1_5 0x04 #define OUTPUT_RATE_3 0x08 #define OUTPUT_RATE_7_5 0x0C #define OUTPUT_RATE_15 0x10 #define OUTPUT_RATE_30 0x14 #define OUTPUT_RATE_75 0x18 #define NORMAL_MEASUREMENT 0x00 #define POSITIVE_BIAS 0x01 #define NEGATIVE_BIAS 0x02 // mode register #define CONTINUOUS_MODE 0x00 #define SINGLE_MODE 0x01 #define IDLE_MODE 0x02 // status register #define STATUS_LOCK 0x02 #define STATUS_READY 0x01 // Utility #ifndef M_PI #define M_PI 3.1415926535897932384626433832795 #endif #define PI2 (2*M_PI) #define RAD_TO_DEG (180.0/M_PI) #define DEG_TO_RAD (M_PI/180.0) /** * The HMC5883L 3-Axis Digital Compass IC */ class HMC5883L { public: /** * The I2C address that can be passed directly to i2c object (it's already shifted 1 bit left). */ static const int I2C_ADDRESS = 0x3D; /** * Constructor. * * Calls init function * * @param sda - mbed pin to use for the SDA I2C line. * @param scl - mbed pin to use for the SCL I2C line. */ HMC5883L(PinName sda, PinName scl); /** * Constructor that accepts external i2c interface object. * * Calls init function * * @param i2c The I2C interface object to use. */ HMC5883L(I2C &i2c) : i2c_(i2c) { init(); } ~HMC5883L(); /** * Initalize function called by all constructors. * * Place startup code in here. */ void init(); /** * Function for setting configuration register A * * Defined constants should be ored together to create value. * Defualt is 0x10 - 1 Sample per output, 15Hz Data output rate, normal measurement mode * * Refer to datasheet for instructions for setting Configuration Register A. * * @param config the value to place in Configuration Register A */ void setConfigurationA(char); /** * Function for retrieving the contents of configuration register A * * @returns Configuration Register A */ char getConfigurationA(); /** * Function for setting configuration register B * * Configuration Register B is for setting the device gain. * Default value is 0x20 * * Refer to datasheet for instructions for setting Configuration Register B * * @param config the value to place in Configuration Register B */ void setConfigurationB(char); /** * Function for retrieving the contents of configuration register B * * @returns Configuration Register B */ char getConfigurationB(); /** * Funciton for setting the mode register * * Constants: CONTINUOUS_MODE, SINGLE_MODE, IDLE_MODE * * When you send a the Single-Measurement Mode instruction to the mode register * a single measurement is made, the RDY bit is set in the status register, * and the mode is placed in idle mode. * * When in Continous-Measurement Mode the device continuously performs measurements * and places the results in teh data register. After being placed in this mode * it takes two periods at the rate set in the data output rate before the first * sample is avaliable. * * Refer to datasheet for more detailed instructions for setting the mode register. * * @param mode the value for setting in the Mode Register */ void setMode(char); /** * Function for retrieving the contents of mode register * * @returns mode register */ char getMode(); /** * Function for retriaval of the raw data * * @param output buffer that is atleast 3 in length */ void getXYZ(int16_t raw[3]); /** * Function for retrieving the contents of status register * * Bit1: LOCK, Bit0: RDY * * @returns status register */ char getStatus(); /** * Function for getting radian heading using 2-dimensional calculation. * * Compass must be held flat and away from an magnetic field generating * devices such as cell phones and speakers. * * TODO: declenation angle compensation * * @returns heading in radians */ double getHeadingXY(); /** * Function for getting degree heading using 2-dimensional calculation. * * Compass must be held flat and away from an magnetic field generating * devices such as cell phones and speakers. * * TODO: declenation angle compensation * * @returns heading in degrees */ double getHeadingXYDeg() { return (getHeadingXY() * RAD_TO_DEG); } private: I2C &i2c_; /** * The raw buffer for allocating I2C object in its own without heap memory. */ char i2cRaw[sizeof(I2C)]; }; #endif // HMC5883L