C++ API for the MMA7660 I2C 3-axis digital accelerometer. More...

Detailed Description

ID: mma7660
Name: mma7660 I2C 3-axis digital accelerometer
Category: accelerometer
Manufacturer: generic
Connection: i2c gpio

UPM module for the MMA7660 I2C 3-axis digital accelerometer. This device supports a variety of capabilities, including the generation of interrupts for various conditions, tilt and basic gesture detection, and of course X/Y/Z measurements of g-forces being applied (up to 1.5g)

This module was tested with the Grove 3-Axis Digital Accelerometer (1.5g)

  // Instantiate an MMA7660 on I2C bus 0
  upm::MMA7660 *accel = new upm::MMA7660(MMA7660_I2C_BUS, 
                                         MMA7660_DEFAULT_I2C_ADDR);
  // place device in standby mode so we can write registers
  accel->setModeStandby();
  // enable 64 samples per second
  accel->setSampleRate(upm::MMA7660::AUTOSLEEP_64);
  
  // place device into active mode
  accel->setModeActive();
  while (shouldRun)
    {
      int x, y, z;
      
      accel->getRawValues(&x, &y, &z);
      cout << "Raw values: x = " << x 
           << " y = " << y
           << " z = " << z
           << endl;
      
      float ax, ay, az;
      
      accel->getAcceleration(&ax, &ay, &az);
      cout << "Acceleration: x = " << ax 
           << "g y = " << ay
           << "g z = " << az
           << "g" << endl;
      
      usleep(500000);
    }

Public Types
enum	MMA7660_REG_T { REG_XOUT = 0x00, REG_YOUT = 0x01, REG_ZOUT = 0x02, REG_TILT = 0x03, REG_SRST = 0x04, REG_SPCNT = 0x05, REG_INTSU = 0x06, REG_MODE = 0x07, REG_SR = 0x08, REG_PDET = 0x09, REG_PD = 0x0a }

enum	MMA7660_INTR_T { INTR_NONE = 0x00, INTR_FBINT = 0x01, INTR_PLINT = 0x02, INTR_PDINT = 0x04, INTR_ASINT = 0x08, INTR_GINT = 0x10, INTR_SHINTZ = 0x20, INTR_SHINTY = 0x40, INTR_SHINTX = 0x80 }

enum	MMA7660_MODE_T { MODE_MODE = 0x01, MODE_TON = 0x04, MODE_AWE = 0x08, MODE_ASE = 0x10, MODE_SCPS = 0x20, MODE_IPP = 0x40, MODE_IAH = 0x80 }

enum	MMA7660_TILT_BF_T { BF_UNKNOWN = 0x00, BF_LYING_FRONT = 0x01, BF_LYING_BACK = 0x02 }

enum	MMA7660_TILT_LP_T { LP_UNKNOWN = 0x00, LP_LANDSCAPE_LEFT = 0x01, LP_LANDSCAPE_RIGHT = 0x02, LP_VERT_DOWN = 0x05, LP_VERT_UP = 0x06 }

enum	MMA7660_AUTOSLEEP_T { AUTOSLEEP_120 = 0x00, AUTOSLEEP_64 = 0x01, AUTOSLEEP_32 = 0x02, AUTOSLEEP_16 = 0x03, AUTOSLEEP_8 = 0x04, AUTOSLEEP_4 = 0x05, AUTOSLEEP_2 = 0x06, AUTOSLEEP_1 = 0x07 }

Public Member Functions
	MMA7660 (int bus, uint8_t address=MMA7660_DEFAULT_I2C_ADDR)

	~MMA7660 ()

bool	writeByte (uint8_t reg, uint8_t byte)

uint8_t	readByte (uint8_t reg)

void	getRawValues (int x, int y, int *z)

void	getAcceleration (float ax, float ay, float *az)

int	getVerifiedAxis (MMA7660_REG_T axis)

uint8_t	getVerifiedTilt ()

void	setModeActive ()

void	setModeStandby ()

uint8_t	tiltBackFront ()

uint8_t	tiltLandscapePortrait ()

bool	tiltTap ()

bool	tiltShake ()

void	installISR (int pin, void(isr)(void ), void *arg)

void	uninstallISR ()

bool	setInterruptBits (uint8_t ibits)

bool	setSampleRate (MMA7660_AUTOSLEEP_T sr)

Constructor & Destructor Documentation

MMA7660	(	int	bus,
		uint8_t	address = `MMA7660_DEFAULT_I2C_ADDR`
	)

mma7660 constructor

Parameters

bus	i2c bus to use
address	the address for this sensor; default is 0x55

~MMA7660 ( )

MMA7660 Destructor

Member Function Documentation

bool writeByte	(	uint8_t	reg,
		uint8_t	byte
	)

Write byte value into register

Parameters

reg	register location to write into
byte	byte to write

Returns: true if successful

uint8_t readByte ( uint8_t reg )

Read byte value from register

Parameters

reg	register location to read from

Returns: value at specified register

void getRawValues	(	int *	x,
		int *	y,
		int *	z
	)

Read current value of conversion

Parameters

x	returned x value
y	returned y value
z	returned z value

void getAcceleration	(	float *	ax,
		float *	ay,
		float *	az
	)

Get the computed acceleration

Parameters

ax	returned computed acceleration of X axis
ay	returned computed acceleration of Y axis
az	returned computed acceleration of Z axis

int getVerifiedAxis ( MMA7660_REG_T axis )

Read an axis, verifying it's validity. The value passed must be one of REG_XOUT, REG_YOUT, or REG_ZOUT.

Parameters

axis	axis to read

Returns: axis value

uint8_t getVerifiedTilt ( )

Read the tilt register, verifying it's validity.

Returns: tilt value

void setModeActive ( )

Put the device into active mode. In active mode, register write are not allowed. Place the device in Standby mode before attempting to write registers.

void setModeStandby ( )

Put the device into Standby (power saving) mode. Note, when in standby mode, there will be no valid data in the registers. In addition, the only way to write a register is to place the device in standby mode.

uint8_t tiltBackFront ( )

Read tilt BackFront bits

The value returned will be one of the MMA7660_TILT_BF_T values

Returns: the bits corresponding to the BackFront tilt status

uint8_t tiltLandscapePortrait ( )

Read tilt LandscapePortrait bits

The value returned will be one of the MMA7660_TILT_LP_T values

Returns: the bits corresponding to the LandscapePortrait tilt status

bool tiltTap ( )

read the tilt Tap status

Returns: true if a tap was detected

bool tiltShake ( )

read the tilt Shake status

Returns: true if a Shake was detected

void installISR	(	int	pin,
		void()(void )	isr,
		void *	arg
	)

Install an Interrupt Service Routine (ISR) to be called when an interrupt occurs

Parameters

pin	gpio pin to use as interrupt pin
fptr	function pointer to function to be called on interrupt
arg	pointer to an object that will be supplied as an argument to the ISR.

void uninstallISR ( )

Uninstall the previously installed Interrupt Service Routine (ISR)

bool setInterruptBits ( uint8_t ibits )

Enable interrupt generation based on the passed interrupt bits. The bits are a bit mask of the requested MMA7660_INTR_T values. Note: The device must be in standby mode to set this register.

Parameters

ibits set the requested interrupt bits

Returns: true if successful

bool setSampleRate ( MMA7660_AUTOSLEEP_T sr )

Set the sampling rate of the sensor. The value supplied must be one of the MMA7660_AUTOSLEEP_T values.

Parameters

sr	one of the MMA7660_AUTOSLEEP_T values

Returns: true if successful

The documentation for this class was generated from the following files:

/var/lib/jenkins/workspace/upm-doc-stable/src/mma7660/mma7660.h
/var/lib/jenkins/workspace/upm-doc-stable/src/mma7660/mma7660.cxx

Detailed Description

Public Types

Public Member Functions

Constructor & Destructor Documentation

Member Function Documentation