Shane Barton / MMA8451Q8

SB-HW-8.1

Fork of MMA8451Q8 by Stanley Cohen

MMA8451Q8b.cpp@8:31f7a3426768, 2017-03-08 (annotated)

Committer:
sbart
Date:
Wed Mar 08 04:11:07 2017 +0000
Revision:
8:31f7a3426768
SB-HW-8.1

Who changed what in which revision?

UserRevisionLine numberNew contents of line
sbart 8:31f7a3426768 1 /* Copyright (c) 2010-2011 mbed.org, MIT License
sbart 8:31f7a3426768 2 *
sbart 8:31f7a3426768 3 * Permission is hereby granted, free of charge, to any person obtaining a copy of this software
sbart 8:31f7a3426768 4 * and associated documentation files (the "Software"), to deal in the Software without
sbart 8:31f7a3426768 5 * restriction, including without limitation the rights to use, copy, modify, merge, publish,
sbart 8:31f7a3426768 6 * distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the
sbart 8:31f7a3426768 7 * Software is furnished to do so, subject to the following conditions:
sbart 8:31f7a3426768 8 *
sbart 8:31f7a3426768 9 * The above copyright notice and this permission notice shall be included in all copies or
sbart 8:31f7a3426768 10 * substantial portions of the Software.
sbart 8:31f7a3426768 11 *
sbart 8:31f7a3426768 12 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
sbart 8:31f7a3426768 13 * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
sbart 8:31f7a3426768 14 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
sbart 8:31f7a3426768 15 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
sbart 8:31f7a3426768 16 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
sbart 8:31f7a3426768 17 */
sbart 8:31f7a3426768 18 // Modify to change full scale gravity range 141207 sc
sbart 8:31f7a3426768 19
sbart 8:31f7a3426768 20
sbart 8:31f7a3426768 21 #include "MMA8451Q8b.h"
sbart 8:31f7a3426768 22
sbart 8:31f7a3426768 23 #define REG_WHO_AM_I 0x0D
sbart 8:31f7a3426768 24 #define REG_CTRL_REG_1 0x2A
sbart 8:31f7a3426768 25 #define REG_OUT_X_MSB 0x01
sbart 8:31f7a3426768 26 #define REG_OUT_Y_MSB 0x03
sbart 8:31f7a3426768 27 #define REG_OUT_Z_MSB 0x05
sbart 8:31f7a3426768 28 #define XYZ_DATA_CFG 0x0E
sbart 8:31f7a3426768 29
sbart 8:31f7a3426768 30 #define UINT14_MAX 16383
sbart 8:31f7a3426768 31
sbart 8:31f7a3426768 32 #define MAX_2G 0x00
sbart 8:31f7a3426768 33 #define MAX_4G 0x01
sbart 8:31f7a3426768 34 #define MAX_8G 0x02
sbart 8:31f7a3426768 35
sbart 8:31f7a3426768 36 #define NUM_DATA 2
sbart 8:31f7a3426768 37 #define GSCALING 1024.0
sbart 8:31f7a3426768 38 #define ADDRESS_INDEX 0
sbart 8:31f7a3426768 39 #define DATA_INDEX 1
sbart 8:31f7a3426768 40
sbart 8:31f7a3426768 41 float gScaling[3] = {4095.0, 2048.0, 1024.0}; //scalin for acceleration of gravity values
sbart 8:31f7a3426768 42
sbart 8:31f7a3426768 43 MMA8451Q::MMA8451Q(PinName sda, PinName scl, int addr) : m_i2c(sda, scl), m_addr(addr) {
sbart 8:31f7a3426768 44 // activate the peripheral
sbart 8:31f7a3426768 45 uint8_t data[2] = {REG_CTRL_REG_1, 0x01};
sbart 8:31f7a3426768 46 writeRegs(data, 2);
sbart 8:31f7a3426768 47 }
sbart 8:31f7a3426768 48
sbart 8:31f7a3426768 49 MMA8451Q::~MMA8451Q() { }
sbart 8:31f7a3426768 50
sbart 8:31f7a3426768 51 uint8_t MMA8451Q::getWhoAmI() {
sbart 8:31f7a3426768 52 uint8_t who_am_i = 0;
sbart 8:31f7a3426768 53 readRegs(REG_WHO_AM_I, &who_am_i, 1);
sbart 8:31f7a3426768 54 return who_am_i;
sbart 8:31f7a3426768 55 }
sbart 8:31f7a3426768 56
sbart 8:31f7a3426768 57 void MMA8451Q::setStandbyMode() {
sbart 8:31f7a3426768 58 #define ACTIVEMASK 0x01
sbart 8:31f7a3426768 59 uint8_t registerData[1];
sbart 8:31f7a3426768 60 uint8_t data[NUM_DATA] = {REG_CTRL_REG_1, 0x00};
sbart 8:31f7a3426768 61
sbart 8:31f7a3426768 62 readRegs(REG_CTRL_REG_1, registerData, 1);
sbart 8:31f7a3426768 63 data[1] = registerData[0] & ~ACTIVEMASK;
sbart 8:31f7a3426768 64 writeRegs(data, NUM_DATA); //put in standby
sbart 8:31f7a3426768 65 }
sbart 8:31f7a3426768 66
sbart 8:31f7a3426768 67 void MMA8451Q::setActiveMode(){
sbart 8:31f7a3426768 68 #define ACTIVEMASK 0x01
sbart 8:31f7a3426768 69 uint8_t registerData[1];
sbart 8:31f7a3426768 70 uint8_t data[NUM_DATA] = {REG_CTRL_REG_1, 0x00};
sbart 8:31f7a3426768 71
sbart 8:31f7a3426768 72 readRegs(REG_CTRL_REG_1, registerData, 1);
sbart 8:31f7a3426768 73 data[1] = registerData[0] | ACTIVEMASK;
sbart 8:31f7a3426768 74 writeRegs(data, NUM_DATA); //put in standby
sbart 8:31f7a3426768 75 }
sbart 8:31f7a3426768 76
sbart 8:31f7a3426768 77 void MMA8451Q::setGLimit(int gSelect) {
sbart 8:31f7a3426768 78 uint8_t data[NUM_DATA] = {REG_CTRL_REG_1, 0x00};
sbart 8:31f7a3426768 79 gChosen = gSelect;
sbart 8:31f7a3426768 80 setStandbyMode();
sbart 8:31f7a3426768 81 data[ADDRESS_INDEX] = XYZ_DATA_CFG;
sbart 8:31f7a3426768 82 data[DATA_INDEX] = gChosen;
sbart 8:31f7a3426768 83 writeRegs(data, 2);// change g limit
sbart 8:31f7a3426768 84 setActiveMode();
sbart 8:31f7a3426768 85 }
sbart 8:31f7a3426768 86
sbart 8:31f7a3426768 87 float MMA8451Q::getAccX() {
sbart 8:31f7a3426768 88 return (float(getAccAxis(REG_OUT_X_MSB))/GSCALING);
sbart 8:31f7a3426768 89 }
sbart 8:31f7a3426768 90
sbart 8:31f7a3426768 91 float MMA8451Q::getAccY() {
sbart 8:31f7a3426768 92 return (float(getAccAxis(REG_OUT_Y_MSB))/GSCALING);
sbart 8:31f7a3426768 93 }
sbart 8:31f7a3426768 94
sbart 8:31f7a3426768 95 float MMA8451Q::getAccZ() {
sbart 8:31f7a3426768 96 return (float(getAccAxis(REG_OUT_Z_MSB))/GSCALING);
sbart 8:31f7a3426768 97 }
sbart 8:31f7a3426768 98
sbart 8:31f7a3426768 99 void MMA8451Q::getAccAllAxis(float * res) {
sbart 8:31f7a3426768 100 res[0] = getAccX();
sbart 8:31f7a3426768 101 res[1] = getAccY();
sbart 8:31f7a3426768 102 res[2] = getAccZ();
sbart 8:31f7a3426768 103 }
sbart 8:31f7a3426768 104
sbart 8:31f7a3426768 105 int16_t MMA8451Q::getAccAxis(uint8_t addr) {
sbart 8:31f7a3426768 106 int16_t acc;
sbart 8:31f7a3426768 107 uint8_t res[2];
sbart 8:31f7a3426768 108 readRegs(addr, res, 2);
sbart 8:31f7a3426768 109
sbart 8:31f7a3426768 110 acc = (res[0] << 6) | (res[1] >> 2);
sbart 8:31f7a3426768 111 if (acc > UINT14_MAX/2)
sbart 8:31f7a3426768 112 acc -= UINT14_MAX;
sbart 8:31f7a3426768 113
sbart 8:31f7a3426768 114 return acc;
sbart 8:31f7a3426768 115 }
sbart 8:31f7a3426768 116
sbart 8:31f7a3426768 117 void MMA8451Q::readRegs(int addr, uint8_t * data, int len) {
sbart 8:31f7a3426768 118 char t[1] = {addr};
sbart 8:31f7a3426768 119 m_i2c.write(m_addr, t, 1, true);
sbart 8:31f7a3426768 120 m_i2c.read(m_addr, (char *)data, len);
sbart 8:31f7a3426768 121 }
sbart 8:31f7a3426768 122
sbart 8:31f7a3426768 123 void MMA8451Q::writeRegs(uint8_t * data, int len) {
sbart 8:31f7a3426768 124 m_i2c.write(m_addr, (char *)data, len);
sbart 8:31f7a3426768 125 }