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