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configure sensors on FRDM KL46Z and send data through Serial port. Need host(PC) software to interact with. Sampling rate can vary by proper instruction
Dependencies: EventFramework mbed
Diff: MMA8451Q.cpp
- Revision:
- 0:2b49a387e831
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/MMA8451Q.cpp Sat Feb 15 07:52:46 2014 +0000 @@ -0,0 +1,185 @@ +/* Copyright (c) 2010-2011 mbed.org, MIT License +* +* Permission is hereby granted, free of charge, to any person obtaining a copy of this software +* and associated documentation files (the "Software"), to deal in the Software without +* restriction, including without limitation the rights to use, copy, modify, merge, publish, +* distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the +* Software is furnished to do so, subject to the following conditions: +* +* The above copyright notice and this permission notice shall be included in all copies or +* substantial portions of the Software. +* +* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING +* BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND +* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, +* DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. +*/ + +#include "MMA8451Q.h" + +#define INT_SOURCE 0x0C +#define REG_WHO_AM_I 0x0D +#define HP_FILTER_CUTOFF 0x0F +#define PULSE_CFG 0x21 +#define PULSE_SRC 0x22 +#define PULSE_THSX 0x23 +#define PULSE_THSY 0x24 +#define PULSE_THSZ 0x25 +#define PULSE_TMLT 0x26 +#define PULSE_LTCY 0x27 +#define PULSE_WIND 0x28 +#define REG_CTRL_REG_1 0x2A +#define CTRL_REG2 0x2B +#define CTRL_REG4 0x2D +#define CTRL_REG5 0x2E +#define REG_OUT_X_MSB 0x01 +#define REG_OUT_Y_MSB 0x03 +#define REG_OUT_Z_MSB 0x05 + +#define UINT14_MAX 16383 + +MMA8451Q::MMA8451Q(PinName sda, PinName scl, int addr) : m_i2c(sda, scl), m_addr(addr),dr(MMA8415Q_SAMPLE400) { + // activate the peripheral + uint8_t data[2] = {REG_CTRL_REG_1, 0x01}; + writeRegs(data, 2); +} + +MMA8451Q::~MMA8451Q() { } + +uint8_t MMA8451Q::getWhoAmI() { + uint8_t who_am_i = 0; + readRegs(REG_WHO_AM_I, &who_am_i, 1); + return who_am_i; +} + +float MMA8451Q::getAccX() { +//divide by 4096 b/c MMA output is 4096 counts per g so this f outputs accelorometer value formatted to g (gravity) + return (float(getAccAxis(REG_OUT_X_MSB))/4096.0); +} + +float MMA8451Q::getAccY() { + return (float(getAccAxis(REG_OUT_Y_MSB))/4096.0); +} + +float MMA8451Q::getAccZ() { + return (float(getAccAxis(REG_OUT_Z_MSB))/4096.0); +} + +void MMA8451Q::getAccAllAxis(float * res) { + res[0] = getAccX(); + res[1] = getAccY(); + res[2] = getAccZ(); +} + +int16_t MMA8451Q::getAccAxis(uint8_t addr) { + int16_t acc; + uint8_t res[2]; + readRegs(addr, res, 2); + + acc = (res[0] << 6) | (res[1] >> 2); + if (acc > UINT14_MAX/2) + acc -= UINT14_MAX; + + return acc; +} + +void MMA8451Q::setDoubleTap(void){ +//Implemented directly from Freescale's AN4072 +//Added to MMA8451Q lib + + uint8_t CTRL_REG1_Data; +// int adds; + uint8_t data[2] = {REG_CTRL_REG_1, dr}; //Sample Rate + + //400 Hz, Standby Mode + writeRegs(data,2); + + //Enable X, Y and Z Double Pulse with DPA = 0 no double pulse abort + data[0]=PULSE_CFG;data[1]=0x2A; + writeRegs(data,2); + + //SetThreshold 3g on X and Y and 5g on Z + //Note: Every step is 0.063g + //3 g/0.063g = 48 counts + //5g/0.063g = 79 counts + data[0]=PULSE_THSX;data[1]=0x30; + writeRegs(data,2);//Set X Threshold to 3g + data[0]=PULSE_THSY;data[1]=0x30; + writeRegs(data,2);//Set Y Threshold to 3g + data[0]=PULSE_THSZ;data[1]=0x4F; + writeRegs(data,2);//Set Z Threshold to 5g + + //Set Time Limit for Tap Detection to 60 ms LP Mode + //Note: 400 Hz ODR, Time step is 1.25 ms per step + //60 ms/1.25 ms = 48 counts + data[0]=PULSE_TMLT;data[1]=0x30; + writeRegs(data,2);//60 ms + + //Set Latency Time to 200 ms + //Note: 400 Hz ODR LPMode, Time step is 2.5 ms per step 00 ms/2.5 ms = 80 counts + data[0]=PULSE_LTCY;data[1]=0x50; + writeRegs(data,2);//200 ms + + //Set Time Window for second tap to 300 ms + //Note: 400 Hz ODR LP Mode, Time step is 2.5 ms per step + //300 ms/2.5 ms = 120 counts + data[0]=PULSE_WIND;data[1]=0x78; + writeRegs(data,2);//300 ms + + //Route INT1 to System Interrupt + data[0]=CTRL_REG4;data[1]=0x08; + writeRegs(data,2);//Enable Pulse Interrupt in System CTRL_REG4 + data[0]=CTRL_REG5;data[1]=0x08; + writeRegs(data,2);//Route Pulse Interrupt to INT1 hardware Pin CTRL_REG5 + + //Set the device to Active Mode + readRegs(0x2A,&CTRL_REG1_Data,1);//Read out the contents of the register + CTRL_REG1_Data |= 0x01; //Change the value in the register to Active Mode. + data[0]=REG_CTRL_REG_1; + data[1]=CTRL_REG1_Data; + writeRegs(data,2);//Write in the updated value to put the device in Active Mode +} + + +void MMA8451Q::readRegs(int addr, uint8_t * data, int len) { + char t[1] = {addr}; + m_i2c.write(m_addr, t, 1, true); + m_i2c.read(m_addr, (char *)data, len); +} + + + +void MMA8451Q::writeRegs(uint8_t * data, int len) { + m_i2c.write(m_addr, (char *)data, len); +} + +void MMA8451Q::Setdr(float dateRate) +{ + if (dateRate==800) + dr=MMA8415Q_SAMPLE800; + else if(dateRate==400) + dr=MMA8415Q_SAMPLE400; + else if(dateRate==200) + dr=MMA8415Q_SAMPLE200; + else if(dateRate==100) + dr=MMA8415Q_SAMPLE100; + else if(dateRate==50) + dr=MMA8415Q_SAMPLE50; + else if(dateRate==12.5) + dr=MMA8415Q_SAMPLE12_5; + else if(dateRate==6.25) + dr=MMA8415Q_SAMPLE6_25; + else if(dateRate==1.56) + dr=MMA8415Q_SAMPLE1_56; +} + +void MMA8451Q::Overwrite_dr(float dateRate) +{ + Setdr(dateRate); +// uint8_t data[2] = {REG_CTRL_REG_1, dr}; //Sample Rate + + //400 Hz, Standby Mode +// writeRegs(data,2); + setDoubleTap(); +} \ No newline at end of file