Guide

1/12/2018 mbed Starter Kit Experiment Guide - learn.sparkfun.com
https://learn.sparkfun.com/tutorials/mbed-starter-kit-experiment-guide/all 25/65
// Library for our MMA8452Q 3-axis accelerometer
// Based on the MMA8452Q Arduino Library by Jim Lindblom (SparkFun Electronics)
#ifndef MMA8452Q_H
#define MMA8452Q_H
#include "mbed.h"
// Register definitions
#define REG_STATUS 0x00
#define OUT_X_MSB 0x01
#define OUT_X_LSB 0x02
#define OUT_Y_MSB 0x03
#define OUT_Y_LSB 0x04
#define OUT_Z_MSB 0x05
#define OUT_Z_LSB 0x06
#define REG_WHO_AM_I 0x0D
#define REG_XYZ_DATA_CFG 0x0E
#define REG_CTRL_REG1 0x2A
// WHO_AM_I check
#define FACTORY_ID 0x2A
// Scale definitions
#define SCALE_2G 2
#define SCALE_4G 4
#define SCALE_8G 8
// Data rates
#define ODR_800HZ 0
#define ODR_400HZ 1
#define ODR_200HZ 2
#define ODR_100HZ 3
#define ODR_50HZ 4
#define ODR_12_5HZ 5
#define ODR_6_25HZ 6
#define ODR_1_56HZ 7
// Init values
#define DEFAULT_FSR SCALE_2G
#define DEFAULT_ODR ODR_800HZ
// Class declaration
class MMA8452Q
{
public:
MMA8452Q(PinName sda, PinName scl, int addr);
~MMA8452Q();
bool init();
uint8_t available();
void setScale(uint8_t fsr);
void setODR(uint8_t odr);
void standby();
void active();
float readX();
float readY();
float readZ();
uint8_t readRegister(uint8_t reg);
void writeRegister(uint8_t reg, uint8_t data);
private:
I2C m_i2c;
int m_addr;
int scale;
};
#endif
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