Tim Hadwen
Device driver for the Freescale MMA845x family of accelerometers.
Diff: MMA845x.h
- Revision:
- 2:555f8ba0c959
- Parent:
- 1:37ddb4739f02
--- a/MMA845x.h Thu Jan 05 06:41:39 2017 +0000
+++ b/MMA845x.h Wed Jan 11 04:12:05 2017 +0000
@@ -1,13 +1,13 @@
/**
* @file MMA845x.h
* @brief Device driver - MMA845x 3-axis accelerometer IC
- * @author sam grove
+ * @author Tim Barr
* @version 1.0
* @see http://cache.freescale.com/files/sensors/doc/data_sheet/MMA8451Q.pdf
* @see http://cache.freescale.com/files/sensors/doc/data_sheet/MMA8452Q.pdf
* @see http://cache.freescale.com/files/sensors/doc/data_sheet/MMA8453Q.pdf
*
- * Copyright (c) 2013
+ * Copyright (c) 2015
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
@@ -20,6 +20,7 @@
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
+ * Forked from
*/
#ifndef MMA845X_H
@@ -52,16 +53,16 @@
{
public:
- volatile uint16_t _x; /*!< volatile data variable */
- volatile uint16_t _y; /*!< volatile data variable */
- volatile uint16_t _z; /*!< volatile data variable */
+ volatile int16_t _x; /*!< volatile data variable */
+ volatile int16_t _y; /*!< volatile data variable */
+ volatile int16_t _z; /*!< volatile data variable */
/** Create the MMA845x_DATA object initialized to the parameter (or 0 if none)
* @param x - the init value of _x
* @param y - the init value of _y
* @param x - the init value of _z
*/
- MMA845x_DATA(uint16_t x = 0, uint16_t y = 0, uint16_t z = 0) : _x(x), _y(y), _z(z) {}
+ MMA845x_DATA(int16_t x = 0, int16_t y = 0, int16_t z = 0) : _x(x), _y(y), _z(z) {}
/** Overloaded '=' operator to allow shorthand coding, assigning objects to one another
* @param rhs - an object of the same type to assign ourself the same values of
@@ -80,7 +81,7 @@
* @param val - Assign each data member (_x, _y, _z) this value
* @return this
*/
- MMA845x_DATA &operator= (uint16_t const val)
+ MMA845x_DATA &operator= (int16_t const val)
{
_x = _y = _z = val;
@@ -95,52 +96,159 @@
{
return ((_x == rhs._x)&&(_y == rhs._y)&&(_z == rhs._z)) ? 1 : 0;
}
-
};
/**
* @class MMA845x
* @brief API abstraction for the MMA845x 3-axis accelerometer IC
+ * initial version will be polling only. Interrupt service and rtos support will
+ * be added at a later point
*/
class MMA845x
{
public:
/**
- * @enum MMA845x_SA0
+ * @enum SA0
* @brief Possible terminations for the ADDR pin
*/
- enum MMA845x_SA0 {
+ enum SA0
+ {
SA0_VSS = 0, /*!< SA0 connected to VSS */
SA0_VDD /*!< SA0 connected to VDD */
};
/**
- * @enum MMA845x_WHO_AM_I
+ * @enum WHO_AM_I_VAL
* @brief Device ID's that this class is compatible with
*/
- enum MMA845x_WHO_AM_I {
+ enum WHO_AM_I_VAL
+ {
MMA8451 = 0x1a, /*!< MMA8451 WHO_AM_I register content */
MMA8452 = 0x2a, /*!< MMA8452 WHO_AM_I register content */
MMA8453 = 0x3a, /*!< MMA8453 WHO_AM_I register content */
};
+
+ /**
+ * @enum SYS_MODE
+ * @brief operating mode of MMA845x
+ */
+ enum SYS_MODE
+ {
+ STANDBY = 0,
+ WAKE, SLEEP
+ };
+
+ /**
+ * @enum STATUS
+ * @brief flags for data overwrite and data ready
+ */
+ enum STATUS
+ {
+ XDR = 0x01,
+ YDR = 0x02,
+ ZDR = 0x04,
+ XYZDR = 0x08,
+ XOW = 0x10,
+ YOW = 0x20,
+ ZOW = 0x40,
+ XYZOW = 0x80
+ };
+
+ /**
+ * @enum RANGE
+ * @brief values for measurement range positive and negative
+ */
+ enum RANGE
+ {
+ RANGE_2g = 0,
+ RANGE_4g, RANGE_8g
+ };
/**
- * @enum MMA845x_REGISTER
+ * @enum RESOLUTION
+ * @brief selections for resolution of data, 8 bit or maximum
+ */
+ enum RESOLUTION
+ {
+ RES_MAX = 0, /* Read back full resolution - normal mode*/
+ RES_8BIT = 2 /* Read back 8 bit values only - fast mode*/
+ };
+
+ /**
+ * @enum LOW_NOISE
+ * @brief Low Noise mode Note: 4g max reading when on
+ */
+ enum LOW_NOISE
+ {
+ LN_OFF = 0x00, /* Low Noise mode off */
+ LN_ON = 0x02 /* Low Noise mode on, 4g max readings */
+ };
+
+ /**
+ * @enum HPF_MODE
+ * @brief High Pass Filter mode
+ */
+ enum HPF_MODE
+ {
+ HPF_OFF = 0x00, /* High Pass Filter mode off */
+ HPF_ON = 0x10 /* High Pass Filter mode on */
+ };
+
+ /**
+ * @enum DATA_RATE
+ * @brief values for normal output data rate in Hz
+ */
+ enum DATA_RATE
+ {
+ DR_800 = 0x00,
+ DR_400 = 0x08,
+ DR_200 = 0x10,
+ DR_100 = 0x18,
+ DR_50 = 0x20,
+ DR_12_5 = 0x28,
+ DR_6_25 = 0x30,
+ DR_1_56 = 0x38
+ };
+ /**
+ * @enum ASLP_DATA_RATE
+ * @brief values for auto_sleep mode data rate in HZ
+ */
+ enum ASLP_DATA_RATE
+ {
+ ASLPDR_50 = 0x00,
+ ALSPDR_12_5 = 0x40,
+ ASLPDR_6_25 = 0x80,
+ ASLPDR_1_56 = 0xB0
+ };
+
+ /**
+ * @enum OVERSAMPLE_MODE
+ * @brief sets the oversample mode, Normal, Low power and noise, High resolution, or low power
+ */
+ enum OVERSAMPLE_MODE
+ {
+ OS_NORMAL = 0,
+ OS_LO_PN, OS_HI_RES, OS_LO_POW
+ };
+
+ /**
+ * @enum REGISTER
* @brief The device register map
*/
- enum MMA845x_REGISTER {
- STATUS = 0x0,
+ enum REGISTER
+ {
+ STATUS = 0x00,
OUT_X_MSB, OUT_X_LSB, OUT_Y_MSB, OUT_Y_LSB, OUT_Z_MSB, OUT_Z_LSB,
- F_SETUP = 0x9, TRIG_CFG, // only available on the MMA8451 variant
+ F_SETUP = 0x09, TRIG_CFG, // only available on the MMA8451 variant
- SYSMOD = 0xb,
+ SYSMOD = 0x0B,
INT_SOURCE, WHO_AM_I, XYZ_DATA_CFG, HP_FILTER_CUTOFF, PL_STATUS,
PL_CFG, PL_COUNT, PL_BF_ZCOMP, P_L_THS_REG, FF_MT_CFG, FF_MT_SRC,
FF_MT_THS, FF_MT_COUNT,
- TRANSIENT_CFG = 0x1d,
+ TRANSIENT_CFG = 0x1D,
TRANSIENT_SRC, TRANSIENT_THS, TRANSIENT_COUNT, PULSE_CFG, PULSE_SRC,
PULSE_THSX, PULSE_THSY, PULSE_THSZ, PULSE_TMLT, PULSE_LTCY, PULSE_WIND,
ASLP_COUNT, CTRL_REG1, CTRL_REG2, CTRL_REG3, CTRL_REG4, CTRL_REG5,
@@ -149,60 +257,104 @@
/** Create the MMA845x object
* @param i2c - A defined I2C object
- * @param int1 - A defined InterruptIn object
- * @param int2 - A defined InterruptIn object
- * @param i2c_addr - Connection of the address line
+ * @param int1 - A defined InterruptIn object pointer. Default NULL for polling mode
+ * @param int2 - A defined InterruptIn object pointer. Default NULL for polling mode
+ * @param i2c_addr - state of pin SA0
+ * TODO - need to add interrupt support
*/
- MMA845x(I2C &i2c, InterruptIn &int1, InterruptIn &int2);
+ MMA845x(I2C &i2c, SA0 const i2c_addr = SA0_VSS, InterruptIn* int1 = NULL, InterruptIn* int2 = NULL);
/** Get the X data
- * @return The last valid reading from the accelerometer
+ * @return The last valid X-axis reading from the accelerometer
*/
- uint16_t getX(void) const;
+ int16_t getX(void);
/** Get the Y data
- * @return The last valid reading from the accelerometer
+ * @return The last valid Y-axis reading from the accelerometer
*/
- uint16_t getY(void) const;
+ int16_t getY(void);
/** Get the Z data
- * @return The last valid reading from the accelerometer
+ * @return The last Z-axis valid reading from the accelerometer
*/
- uint16_t getZ(void) const;
+ int16_t getZ(void);
+
+ /** Get the XYZ data structure
+ * @return The last valid X, Y, and Z-axis readings from the accelerometer
+ */
+ MMA845x_DATA getXYZ(void);
/** Get the XYZ data structure
- * @return The last valid reading from the accelerometer
+ * @return accelerometer ID code. Test versus the WHO_AM_I_VAL enum
+ */
+ char getWhoAmI(void) const;
+
+ /** Setup the MMA845x for standard accelerometer read mode
+ * @range - set the measurement range using RANGE enum
+ * @resolution - set the ADC resolution using the RESOLUTION enum
+ * @lo_noise - Set the Low-Noise mode using the LOW_NOISE enum
+ * @data_rate - set the aquisition rate using the DATA_RATE enum
+ * @os_mode - Set the Over sample mode suing the OVERSAMPLE_MODE enum
+ * @hpf_mode - Set the Hi pass filter mode using the HPF_MOSE enum
+ * @return status of command
+ *
+ * This sets the resolution, range, data rate, oversample
+ * mode, hi and lo pass filter.
+ */
+ uint8_t setCommonParameters(RANGE range, RESOLUTION resolution, LOW_NOISE lo_noise,
+ DATA_RATE data_rate, OVERSAMPLE_MODE os_mode, HPF_MODE hpf_mode ) const;
+
+ /** Ebnable Motion detect mode and interrupt handler
+ * @return status of command
+ * TODO - need to implement function
*/
- MMA845x_DATA getXYZ(void) const;
-
- void enableDataReadyMode(void) const;
- void enableMotionMode(void) const;
- void enablePulseMode(void) const;
- void enableOrientationMode(void) const;
- void enableTransitMode(void) const;
- void enableAutoSleepMode(void) const;
- void enableFIFOMode(void) const;
-
- /** Put the MMA845x in the lowest possible power mode and suspend operation
+ uint8_t enableMotionDetect(void) const;
+
+ /** Enable Pulse Detect mode and interrupt handler
+ * @return status of command
+ * TODO - need to implement function
+ */
+ uint8_t enablePulseDetect(void) const;
+
+ /** Enable Orientation mode and interrupt handler
+ * @return status of command
+ * TODO - need to implement function
*/
- void disable(void);
+ uint8_t enableOrientationDetect(void) const;
+
+ /** Enable Transient detect mode and interrupt handler
+ * @return status of command
+ * TODO - need to implement function
+ */
+ uint8_t enableTransientDetect(void) const;
+
+ /** Enable Autosleep function and interrupt handler
+ * @return status of command
+ * TODO - need to implement function
+ */
+ uint8_t enableAutoSleep(void) const;
+
+ /** Enbale FIFO function and interrupt handler
+ * @return status of command
+ * TODO - need to implement function
+ */
+ uint8_t enableFIFO(void) const;
- /** Write to a register (exposed for debugging reasons)
- * Note: most writes are only valid in stop mode
- * @param reg - The register to be written
- * @param data - The data to be written
+ /** Put the MMA845x in the Standby mode
+ * @return status of command
*/
- void writeRegister(uint8_t const reg, uint8_t const data) const;
+ uint8_t standbyMode(void) const;
+
+ /** Put the MMA845x in the active mode
+ * @return status of command
+ */
+ uint8_t activeMode(void) const;
- /** Read from a register (exposed for debugging reasons)
- * @param reg - The register to read from
- * @return The register contents
- */
- uint8_t readRegister(uint8_t const reg) const;
-
- /** print the register map and values to the console
- */
- void registerDump(void) const;
+ /** Check the MMA845x status register
+ * @return status byte
+ */
+ uint8_t getStatus(void) const;
+
private:
@@ -210,9 +362,26 @@
InterruptIn *_int1;
InterruptIn *_int2;
uint8_t _i2c_addr;
+ char _who_am_i;
MMA845x_DATA _data;
+ bool _polling_mode;
+
+ uint8_t init(void);
- void init(void) const;
+ /** Write to a register (exposed for debugging reasons)
+ * Note: most writes are only valid in stop mode
+ * @param reg - The register to be written
+ * @param data - The data to be written
+ */
+ uint8_t writeRegister(uint8_t const reg, uint8_t const data) const;
+
+ /** Read from a register (exposed for debugging reasons)
+ * @param reg - The register to read from
+ * @return The register contents
+ */
+ uint8_t readRegister(uint8_t const reg, uint8_t count, char* data) const;
+
+
};
#endif