Jorge Hernandez / MMA8451Q

Modified to also return int16_t values.

Fork of MMA8451Q by Johan Kritzinger

MMA8451Q.cpp@6:2511055a5dd2, 2013-06-07 (annotated)

Committer:
jhestolano
Date:
Fri Jun 07 03:14:46 2013 +0000
Revision:
6:2511055a5dd2
Parent:
5:2d14600116fc 
Modified to return int16_t values instead of float type.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
samux 1:d2630136d51e 1 /* Copyright (c) 2010-2011 mbed.org, MIT License
samux 1:d2630136d51e 2 *
samux 1:d2630136d51e 3 * Permission is hereby granted, free of charge, to any person obtaining a copy of this software
samux 1:d2630136d51e 4 * and associated documentation files (the "Software"), to deal in the Software without
samux 1:d2630136d51e 5 * restriction, including without limitation the rights to use, copy, modify, merge, publish,
samux 1:d2630136d51e 6 * distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the
samux 1:d2630136d51e 7 * Software is furnished to do so, subject to the following conditions:
samux 1:d2630136d51e 8 *
samux 1:d2630136d51e 9 * The above copyright notice and this permission notice shall be included in all copies or
samux 1:d2630136d51e 10 * substantial portions of the Software.
samux 1:d2630136d51e 11 *
samux 1:d2630136d51e 12 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
samux 1:d2630136d51e 13 * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
samux 1:d2630136d51e 14 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
samux 1:d2630136d51e 15 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
samux 1:d2630136d51e 16 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
samux 1:d2630136d51e 17 */
samux 1:d2630136d51e 18
emilmont 0:6149091f755d 19 #include "MMA8451Q.h"
emilmont 0:6149091f755d 20
JoKer 5:2d14600116fc 21 #define INT_SOURCE 0x0C
samux 1:d2630136d51e 22 #define REG_WHO_AM_I 0x0D
JoKer 5:2d14600116fc 23 #define HP_FILTER_CUTOFF 0x0F
JoKer 5:2d14600116fc 24 #define PULSE_CFG 0x21
JoKer 5:2d14600116fc 25 #define PULSE_SRC 0x22
JoKer 5:2d14600116fc 26 #define PULSE_THSX 0x23
JoKer 5:2d14600116fc 27 #define PULSE_THSY 0x24
JoKer 5:2d14600116fc 28 #define PULSE_THSZ 0x25
JoKer 5:2d14600116fc 29 #define PULSE_TMLT 0x26
JoKer 5:2d14600116fc 30 #define PULSE_LTCY 0x27
JoKer 5:2d14600116fc 31 #define PULSE_WIND 0x28
JoKer 5:2d14600116fc 32 #define REG_CTRL_REG_1 0x2A
JoKer 5:2d14600116fc 33 #define CTRL_REG2 0x2B
JoKer 5:2d14600116fc 34 #define CTRL_REG4 0x2D
JoKer 5:2d14600116fc 35 #define CTRL_REG5 0x2E
emilmont 0:6149091f755d 36 #define REG_OUT_X_MSB 0x01
emilmont 0:6149091f755d 37 #define REG_OUT_Y_MSB 0x03
emilmont 0:6149091f755d 38 #define REG_OUT_Z_MSB 0x05
emilmont 0:6149091f755d 39
samux 1:d2630136d51e 40 #define UINT14_MAX 16383
emilmont 0:6149091f755d 41
emilmont 0:6149091f755d 42 MMA8451Q::MMA8451Q(PinName sda, PinName scl, int addr) : m_i2c(sda, scl), m_addr(addr) {
emilmont 0:6149091f755d 43 // activate the peripheral
emilmont 0:6149091f755d 44 uint8_t data[2] = {REG_CTRL_REG_1, 0x01};
samux 1:d2630136d51e 45 writeRegs(data, 2);
emilmont 0:6149091f755d 46 }
emilmont 0:6149091f755d 47
emilmont 0:6149091f755d 48 MMA8451Q::~MMA8451Q() { }
emilmont 0:6149091f755d 49
emilmont 0:6149091f755d 50 uint8_t MMA8451Q::getWhoAmI() {
emilmont 0:6149091f755d 51 uint8_t who_am_i = 0;
samux 1:d2630136d51e 52 readRegs(REG_WHO_AM_I, &who_am_i, 1);
emilmont 0:6149091f755d 53 return who_am_i;
emilmont 0:6149091f755d 54 }
emilmont 0:6149091f755d 55
chris 3:db7126dbd63f 56 float MMA8451Q::getAccX() {
JoKer 5:2d14600116fc 57 //divide by 4096 b/c MMA output is 4096 counts per g so this f outputs accelorometer value formatted to g (gravity)
chris 3:db7126dbd63f 58 return (float(getAccAxis(REG_OUT_X_MSB))/4096.0);
emilmont 0:6149091f755d 59 }
emilmont 0:6149091f755d 60
chris 3:db7126dbd63f 61 float MMA8451Q::getAccY() {
chris 3:db7126dbd63f 62 return (float(getAccAxis(REG_OUT_Y_MSB))/4096.0);
emilmont 0:6149091f755d 63 }
emilmont 0:6149091f755d 64
chris 3:db7126dbd63f 65 float MMA8451Q::getAccZ() {
chris 3:db7126dbd63f 66 return (float(getAccAxis(REG_OUT_Z_MSB))/4096.0);
emilmont 0:6149091f755d 67 }
emilmont 0:6149091f755d 68
chris 3:db7126dbd63f 69 void MMA8451Q::getAccAllAxis(float * res) {
emilmont 0:6149091f755d 70 res[0] = getAccX();
emilmont 0:6149091f755d 71 res[1] = getAccY();
emilmont 0:6149091f755d 72 res[2] = getAccZ();
emilmont 0:6149091f755d 73 }
emilmont 0:6149091f755d 74
jhestolano 6:2511055a5dd2 75 int16_t MMA8451Q::getAccX_int() {
jhestolano 6:2511055a5dd2 76 return getAccAxis(REG_OUT_X_MSB);
jhestolano 6:2511055a5dd2 77 }
jhestolano 6:2511055a5dd2 78
jhestolano 6:2511055a5dd2 79 int16_t MMA8451Q::getAccY_int() {
jhestolano 6:2511055a5dd2 80 return getAccAxis(REG_OUT_Y_MSB);
jhestolano 6:2511055a5dd2 81 }
jhestolano 6:2511055a5dd2 82
jhestolano 6:2511055a5dd2 83 int16_t MMA8451Q::getAccZ_int() {
jhestolano 6:2511055a5dd2 84 return getAccAxis(REG_OUT_Z_MSB);
jhestolano 6:2511055a5dd2 85 }
jhestolano 6:2511055a5dd2 86
jhestolano 6:2511055a5dd2 87 void MMA8451Q::getAccAllAxis_int(int16_t* res) {
jhestolano 6:2511055a5dd2 88 res[0] = getAccX_int();
jhestolano 6:2511055a5dd2 89 res[1] = getAccY_int();
jhestolano 6:2511055a5dd2 90 res[2] = getAccZ_int();
jhestolano 6:2511055a5dd2 91 }
jhestolano 6:2511055a5dd2 92
emilmont 0:6149091f755d 93 int16_t MMA8451Q::getAccAxis(uint8_t addr) {
emilmont 0:6149091f755d 94 int16_t acc;
emilmont 0:6149091f755d 95 uint8_t res[2];
samux 1:d2630136d51e 96 readRegs(addr, res, 2);
emilmont 0:6149091f755d 97
emilmont 0:6149091f755d 98 acc = (res[0] << 6) | (res[1] >> 2);
emilmont 0:6149091f755d 99 if (acc > UINT14_MAX/2)
emilmont 0:6149091f755d 100 acc -= UINT14_MAX;
emilmont 0:6149091f755d 101
emilmont 0:6149091f755d 102 return acc;
emilmont 0:6149091f755d 103 }
emilmont 0:6149091f755d 104
JoKer 5:2d14600116fc 105 void MMA8451Q::setDoubleTap(void){
JoKer 5:2d14600116fc 106 //Implemented directly from Freescale's AN4072
JoKer 5:2d14600116fc 107 //Added to MMA8451Q lib
JoKer 5:2d14600116fc 108
JoKer 5:2d14600116fc 109 uint8_t CTRL_REG1_Data;
JoKer 5:2d14600116fc 110 // int adds;
JoKer 5:2d14600116fc 111 uint8_t data[2] = {REG_CTRL_REG_1, 0x08};
JoKer 5:2d14600116fc 112
JoKer 5:2d14600116fc 113 //400 Hz, Standby Mode
JoKer 5:2d14600116fc 114 writeRegs(data,2);
JoKer 5:2d14600116fc 115
JoKer 5:2d14600116fc 116 //Enable X, Y and Z Double Pulse with DPA = 0 no double pulse abort
JoKer 5:2d14600116fc 117 data[0]=PULSE_CFG;data[1]=0x2A;
JoKer 5:2d14600116fc 118 writeRegs(data,2);
JoKer 5:2d14600116fc 119
JoKer 5:2d14600116fc 120 //SetThreshold 3g on X and Y and 5g on Z
JoKer 5:2d14600116fc 121 //Note: Every step is 0.063g
JoKer 5:2d14600116fc 122 //3 g/0.063g = 48 counts
JoKer 5:2d14600116fc 123 //5g/0.063g = 79 counts
JoKer 5:2d14600116fc 124 data[0]=PULSE_THSX;data[1]=0x30;
JoKer 5:2d14600116fc 125 writeRegs(data,2);//Set X Threshold to 3g
JoKer 5:2d14600116fc 126 data[0]=PULSE_THSY;data[1]=0x30;
JoKer 5:2d14600116fc 127 writeRegs(data,2);//Set Y Threshold to 3g
JoKer 5:2d14600116fc 128 data[0]=PULSE_THSZ;data[1]=0x4F;
JoKer 5:2d14600116fc 129 writeRegs(data,2);//Set Z Threshold to 5g
JoKer 5:2d14600116fc 130
JoKer 5:2d14600116fc 131 //Set Time Limit for Tap Detection to 60 ms LP Mode
JoKer 5:2d14600116fc 132 //Note: 400 Hz ODR, Time step is 1.25 ms per step
JoKer 5:2d14600116fc 133 //60 ms/1.25 ms = 48 counts
JoKer 5:2d14600116fc 134 data[0]=PULSE_TMLT;data[1]=0x30;
JoKer 5:2d14600116fc 135 writeRegs(data,2);//60 ms
JoKer 5:2d14600116fc 136
JoKer 5:2d14600116fc 137 //Set Latency Time to 200 ms
JoKer 5:2d14600116fc 138 //Note: 400 Hz ODR LPMode, Time step is 2.5 ms per step 00 ms/2.5 ms = 80 counts
JoKer 5:2d14600116fc 139 data[0]=PULSE_LTCY;data[1]=0x50;
JoKer 5:2d14600116fc 140 writeRegs(data,2);//200 ms
JoKer 5:2d14600116fc 141
JoKer 5:2d14600116fc 142 //Set Time Window for second tap to 300 ms
JoKer 5:2d14600116fc 143 //Note: 400 Hz ODR LP Mode, Time step is 2.5 ms per step
JoKer 5:2d14600116fc 144 //300 ms/2.5 ms = 120 counts
JoKer 5:2d14600116fc 145 data[0]=PULSE_WIND;data[1]=0x78;
JoKer 5:2d14600116fc 146 writeRegs(data,2);//300 ms
JoKer 5:2d14600116fc 147
JoKer 5:2d14600116fc 148 //Route INT1 to System Interrupt
JoKer 5:2d14600116fc 149 data[0]=CTRL_REG4;data[1]=0x08;
JoKer 5:2d14600116fc 150 writeRegs(data,2);//Enable Pulse Interrupt in System CTRL_REG4
JoKer 5:2d14600116fc 151 data[0]=CTRL_REG5;data[1]=0x08;
JoKer 5:2d14600116fc 152 writeRegs(data,2);//Route Pulse Interrupt to INT1 hardware Pin CTRL_REG5
JoKer 5:2d14600116fc 153
JoKer 5:2d14600116fc 154 //Set the device to Active Mode
JoKer 5:2d14600116fc 155 readRegs(0x2A,&CTRL_REG1_Data,1);//Read out the contents of the register
JoKer 5:2d14600116fc 156 CTRL_REG1_Data |= 0x01; //Change the value in the register to Active Mode.
JoKer 5:2d14600116fc 157 data[0]=REG_CTRL_REG_1;
JoKer 5:2d14600116fc 158 data[1]=CTRL_REG1_Data;
JoKer 5:2d14600116fc 159 writeRegs(data,2);//Write in the updated value to put the device in Active Mode
JoKer 5:2d14600116fc 160 }
JoKer 5:2d14600116fc 161
JoKer 5:2d14600116fc 162
samux 1:d2630136d51e 163 void MMA8451Q::readRegs(int addr, uint8_t * data, int len) {
emilmont 0:6149091f755d 164 char t[1] = {addr};
emilmont 0:6149091f755d 165 m_i2c.write(m_addr, t, 1, true);
emilmont 0:6149091f755d 166 m_i2c.read(m_addr, (char *)data, len);
emilmont 0:6149091f755d 167 }
emilmont 0:6149091f755d 168
JoKer 5:2d14600116fc 169
JoKer 5:2d14600116fc 170
samux 1:d2630136d51e 171 void MMA8451Q::writeRegs(uint8_t * data, int len) {
emilmont 0:6149091f755d 172 m_i2c.write(m_addr, (char *)data, len);
emilmont 0:6149091f755d 173 }