Revision 0:5a09d01c6a2c, committed 2015-12-25

Comitter:

Rhyme

Date:

Fri Dec 25 07:21:49 2015 +0000

Commit message:

First commit, only the minimum functions have been implemented.

Changed in this revision

diff -r 000000000000 -r 5a09d01c6a2c MMA8451Q.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MMA8451Q.cpp	Fri Dec 25 07:21:49 2015 +0000
@@ -0,0 +1,128 @@
+/**
+ * MMA8451Q 3-Axis, 14-bit/8-bit Digital Accelerometer
+ */
+ 
+#include "mbed.h"
+#include "MMA8451Q.h"
+
+#define REG_STATUS           0x00 // when F_MODE = 00
+#define REG_FIFO_STATUS      0x00 // when F_MODE > 0
+#define REG_XYZ_FIFO         0x01 // Root pointer to XYZ FIFO data
+#define REG_OUT_X_MSB        0x01 // 8 MSBs of 14-bit sample
+#define REG_OUT_X_LSB        0x02 // 6 LSBs of 14-bit sample
+#define REG_OUT_Y_MSB        0x03 
+#define REG_OUT_Y_LSB        0x04
+#define REG_OUT_Z_MSB        0x05
+#define REG_OUT_Z_LSB        0x06
+#define REG_F_SETUP          0x09 // FIFO setup
+#define REG_TRIG_CFG         0x0A // Map of FIFO daa capture events
+#define REG_SYSMOD           0x0B // Current System Mode
+#define REG_INT_SOURCE       0x0C // Interrupt status
+#define REG_WHO_AM_I         0x0D // Device ID (0x1A)
+#define REG_XYZ_DATA_CFG     0x0E // Dynamic Range Settings
+#define REG_HP_FILTER_CUTOFF 0x0F // Cutoff freq is set to 16Hz@800Hz
+#define REG_PL_STATUS        0x10 // Landscape/Portrait orientation status
+#define REG_PL_CFG           0x11 // Landscape/Portrait configuration
+#define REG_PL_COUNT         0x12 // Landscape/Portrait debounce counter 
+#define REG_PL_BF_ZCOMP      0x13 // Back/Front, Z-Lock Trip threshold
+#define REG_P_L_THS_REG      0x14 // Portrait to Landscape Trip Angle is 29 degree
+#define REG_FF_MT_CFG        0x15 // Freefall/Motion function block configuration
+#define REG_FF_MT_SRC        0x16 // Freefall/Motion event source register
+#define REG_FF_MT_THS        0x17 // Freefall/Motion threshold register
+#define REG_FF_MT_COUNT      0x18 // Freefall/Motion debounce counter
+// TRANSIENT
+#define REG_TRANSIENT_CFG    0x1D // Transient functional block configuration
+#define REG_TRANSIENT_SRC    0x1E // Transient event status register
+#define REG_TRANSIENT_THS    0x1F // Transient event threshold
+#define REG_TRANSIENT_COUNT  0x20 // Transient debounce counter
+// PULSE
+#define REG_PULSE_CFG        0x21 // ELE, Double_XYZ or Single_XYZ
+#define REG_PULSE_SRC        0x22 // EA, Double_XYZ or Single_XYZ
+#define REG_PULSE_THSX       0x23 // X pulse threshold
+#define REG_PULSE_THSY       0x24 // Y pulse threshold
+#define REG_PULSE_THSZ       0x25 // Z pulse threshold
+#define REG_PULSE_TMLT       0x26 // Time limit for pulse
+#define REG_PULSE_LTCY       0x27 // Latency time for 2nd pulse
+#define REG_PULSE_WIND       0x28 // Window time for 2nd pulse
+#define REG_ASLP_COUNT       0x29 // Counter setting for Auto-SLEEP
+// Control Registers
+#define REG_CTRL_REG1        0x2A // ODR = 800Hz, STANDBY Mode
+#define REG_CTRL_REG2        0x2B // Sleep Enable, OS Modes, RST, ST
+#define REG_CTRL_REG3        0x2C // Wake from Sleep, IPOL, PP_OD
+#define REG_CTRL_REG4        0x2D // Interrupt enable register
+#define REG_CTRL_REG5        0x2E // Interrupt pin (INT1/INT2) map
+// User Offset
+#define REG_OFF_X            0x2F // X-axis offset adjust
+#define REG_OFF_Y            0x30 // Y-axis offset adjust
+#define REG_OFF_Z            0x31 // Z-axis offset adjust
+
+// Value definitions
+#define BIT_TRIG_TRANS       0x20  // Transient interrupt trigger bit
+#define BIT_TRIG_LNDPRT      0x10  // Landscape/Portrati Orientation
+#define BIT_TRIG_PULSE       0x08  // Pulse interrupt trigger bit
+#define BIT_TRIG_FF_MT       0x04  // Freefall/Motion trigger bit
+
+MMA8451Q::MMA8451Q(PinName sda, PinName scl, int addr) : m_i2c(sda, scl), m_addr(addr<<1) {
+    // activate the peripheral
+    uint8_t data[2] = {REG_CTRL_REG1, 0x01};
+    writeRegs(data, 2);
+}
+
+MMA8451Q::~MMA8451Q() { }
+
+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);
+}
+
+int16_t MMA8451Q::getRawData(uint8_t addr)
+{
+    int16_t value ;
+    uint8_t data[2] ;
+    readRegs(addr, data, 2) ;
+    value = ((int16_t)((data[0] << 8) | data[1])) >> 2 ;
+    return( value ) ;
+}
+
+int16_t MMA8451Q::getRawX(void) 
+{
+    int16_t value ;
+    value = getRawData(REG_OUT_X_MSB) ;
+    return( value ) ;
+}
+
+int16_t MMA8451Q::getRawY(void) 
+{
+    int16_t value ;
+    value = getRawData(REG_OUT_Y_MSB) ;
+    return( value ) ;
+}
+
+int16_t MMA8451Q::getRawZ(void) 
+{
+    int16_t value ;
+    value = getRawData(REG_OUT_Z_MSB) ;
+    return( value ) ;
+}
+  
+float MMA8451Q::getAccX(void)
+{
+    return(((float)getRawX())/4096.0) ;
+}
+
+float MMA8451Q::getAccY(void) 
+{
+    return(((float)getRawY())/4096.0) ;
+}
+
+float MMA8451Q::getAccZ(void) 
+{
+    return(((float)getRawZ())/4096.0) ;
+}
\ No newline at end of file

diff -r 000000000000 -r 5a09d01c6a2c MMA8451Q.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MMA8451Q.h	Fri Dec 25 07:21:49 2015 +0000
@@ -0,0 +1,41 @@
+/**
+ * MMA8451Q 3-Axis, 14-bit/8-bit Digital Accelerometer
+ */
+#ifndef _MMA8451Q_H_
+#define _MMA8451Q_H_
+
+#include "mbed.h"
+
+class MMA8451Q {
+public:
+  /**
+  * MMA8451Q constructor
+  *
+  * @param sda SDA pin
+  * @param sdl SCL pin
+  * @param addr 7bit addr of the I2C peripheral
+  */
+  MMA8451Q(PinName sda, PinName scl, int addr);
+
+  /**
+  * MMA8451Q destructor
+  */
+  ~MMA8451Q();
+  
+  int16_t getRawData(uint8_t addr) ;
+  int16_t getRawX(void) ;
+  int16_t getRawY(void) ;
+  int16_t getRawZ(void) ;
+  
+  float getAccX(void) ;
+  float getAccY(void) ;
+  float getAccZ(void) ;
+  
+private:
+  I2C m_i2c;
+  int m_addr;
+  void readRegs(int addr, uint8_t * data, int len);
+  void writeRegs(uint8_t * data, int len);
+} ;
+
+#endif /* _MMA8451Q_H_ */
\ No newline at end of file