Lee Kai Xuan / mbed-os

mbed-os

Fork of mbed-os by erkin yucel

features/unsupported/tests/peripherals/MMA8451Q/MMA8451Q.cpp@0:f269e3021894, 2016-10-23 (annotated)

Committer:
elessair
Date:
Sun Oct 23 15:10:02 2016 +0000
Revision:
0:f269e3021894
Initial commit

Who changed what in which revision?

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elessair 0:f269e3021894 1 /* Copyright (c) 2010-2011 mbed.org, MIT License
elessair 0:f269e3021894 2 *
elessair 0:f269e3021894 3 * Permission is hereby granted, free of charge, to any person obtaining a copy of this software
elessair 0:f269e3021894 4 * and associated documentation files (the "Software"), to deal in the Software without
elessair 0:f269e3021894 5 * restriction, including without limitation the rights to use, copy, modify, merge, publish,
elessair 0:f269e3021894 6 * distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the
elessair 0:f269e3021894 7 * Software is furnished to do so, subject to the following conditions:
elessair 0:f269e3021894 8 *
elessair 0:f269e3021894 9 * The above copyright notice and this permission notice shall be included in all copies or
elessair 0:f269e3021894 10 * substantial portions of the Software.
elessair 0:f269e3021894 11 *
elessair 0:f269e3021894 12 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
elessair 0:f269e3021894 13 * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
elessair 0:f269e3021894 14 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
elessair 0:f269e3021894 15 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
elessair 0:f269e3021894 16 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
elessair 0:f269e3021894 17 */
elessair 0:f269e3021894 18
elessair 0:f269e3021894 19 #include "MMA8451Q.h"
elessair 0:f269e3021894 20
elessair 0:f269e3021894 21 #define REG_WHO_AM_I 0x0D
elessair 0:f269e3021894 22 #define REG_CTRL_REG_1 0x2A
elessair 0:f269e3021894 23 #define REG_OUT_X_MSB 0x01
elessair 0:f269e3021894 24 #define REG_OUT_Y_MSB 0x03
elessair 0:f269e3021894 25 #define REG_OUT_Z_MSB 0x05
elessair 0:f269e3021894 26
elessair 0:f269e3021894 27 #define UINT14_MAX 16383
elessair 0:f269e3021894 28
elessair 0:f269e3021894 29 MMA8451Q::MMA8451Q(PinName sda, PinName scl, int addr) : m_i2c(sda, scl), m_addr(addr) {
elessair 0:f269e3021894 30 // activate the peripheral
elessair 0:f269e3021894 31 uint8_t data[2] = {REG_CTRL_REG_1, 0x01};
elessair 0:f269e3021894 32 writeRegs(data, 2);
elessair 0:f269e3021894 33 }
elessair 0:f269e3021894 34
elessair 0:f269e3021894 35 MMA8451Q::~MMA8451Q() { }
elessair 0:f269e3021894 36
elessair 0:f269e3021894 37 uint8_t MMA8451Q::getWhoAmI() {
elessair 0:f269e3021894 38 uint8_t who_am_i = 0;
elessair 0:f269e3021894 39 readRegs(REG_WHO_AM_I, &who_am_i, 1);
elessair 0:f269e3021894 40 return who_am_i;
elessair 0:f269e3021894 41 }
elessair 0:f269e3021894 42
elessair 0:f269e3021894 43 int16_t MMA8451Q::getAccX() {
elessair 0:f269e3021894 44 return getAccAxis(REG_OUT_X_MSB);
elessair 0:f269e3021894 45 }
elessair 0:f269e3021894 46
elessair 0:f269e3021894 47 int16_t MMA8451Q::getAccY() {
elessair 0:f269e3021894 48 return getAccAxis(REG_OUT_Y_MSB);
elessair 0:f269e3021894 49 }
elessair 0:f269e3021894 50
elessair 0:f269e3021894 51 int16_t MMA8451Q::getAccZ() {
elessair 0:f269e3021894 52 return getAccAxis(REG_OUT_Z_MSB);
elessair 0:f269e3021894 53 }
elessair 0:f269e3021894 54
elessair 0:f269e3021894 55 void MMA8451Q::getAccAllAxis(int16_t * res) {
elessair 0:f269e3021894 56 res[0] = getAccX();
elessair 0:f269e3021894 57 res[1] = getAccY();
elessair 0:f269e3021894 58 res[2] = getAccZ();
elessair 0:f269e3021894 59 }
elessair 0:f269e3021894 60
elessair 0:f269e3021894 61 int16_t MMA8451Q::getAccAxis(uint8_t addr) {
elessair 0:f269e3021894 62 int16_t acc;
elessair 0:f269e3021894 63 uint8_t res[2];
elessair 0:f269e3021894 64 readRegs(addr, res, 2);
elessair 0:f269e3021894 65
elessair 0:f269e3021894 66 acc = (res[0] << 6) | (res[1] >> 2);
elessair 0:f269e3021894 67 if (acc > UINT14_MAX/2)
elessair 0:f269e3021894 68 acc -= UINT14_MAX;
elessair 0:f269e3021894 69
elessair 0:f269e3021894 70 return acc;
elessair 0:f269e3021894 71 }
elessair 0:f269e3021894 72
elessair 0:f269e3021894 73 void MMA8451Q::readRegs(int addr, uint8_t * data, int len) {
elessair 0:f269e3021894 74 char t[1] = {addr};
elessair 0:f269e3021894 75 m_i2c.write(m_addr, t, 1, true);
elessair 0:f269e3021894 76 m_i2c.read(m_addr, (char *)data, len);
elessair 0:f269e3021894 77 }
elessair 0:f269e3021894 78
elessair 0:f269e3021894 79 void MMA8451Q::writeRegs(uint8_t * data, int len) {
elessair 0:f269e3021894 80 m_i2c.write(m_addr, (char *)data, len);
elessair 0:f269e3021894 81 }