MMA7660 Class Reference

API for the MMA7660 I2C 3-Axis Digital Accelerometer. More...

Detailed Description

• ID: mma7660
• Name: I2C 3-axis Digital Accelerometer (1.5g)
• Other Names: Grove 3-Axis Digital Accelerometer (1.5g)
• Category: accelerometer
• Manufacturer: seeed
• Connection: i2c gpio
• Link: http://www.nxp.com/products/sensors/accelerometers/3-axis-accelerometers/1.5g-low-g-digital-accelerometer:MMA7660FC

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 X/Y/Z-axis 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(MMA7660_DEFAULT_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(MMA7660_AUTOSLEEP_64);

    // place device into active mode
    accel.setModeActive();

    while (shouldRun) {
        float ax, ay, az;

        accel.getAcceleration(&ax, &ay, &az);
        cout << "Acceleration: x = " << ax << "g y = " << ay << "g z = " << az << "g" << endl;

        cout << endl;
        upm_delay_us(500000);
    }

Public Member Functions
	MMA7660 (int bus, uint8_t address=MMA7660_DEFAULT_I2C_ADDR)
virtual	~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	uninstallISR ()
bool	setInterruptBits (uint8_t ibits)
bool	setSampleRate (MMA7660_AUTOSLEEP_T sr)
void	installISR (int pin, void(*isr)(void *), void *arg)

Protected Attributes
mma7660_context	m_mma7660

Constructor & Destructor Documentation

MMA7660	(	int	bus,
		uint8_t	address = MMA7660_DEFAULT_I2C_ADDR
	)

MMA7660 constructor

Parameters

bus	I2C bus to use
address	Address for this sensor; default is 0x55

~MMA7660 ( )

virtual

MMA7660 destructor

Here is the call graph for this function:

Member Function Documentation

bool writeByte	(	uint8_t	reg,
		uint8_t	byte
	)

Writes a byte value into a register

Parameters

reg	Register location to write into
byte	Byte to write

Returns

True if successful

Here is the call graph for this function:

uint8_t readByte

(

uint8_t

reg

)

Reads a byte value from a register

Parameters

reg	Register location to read from

Returns

Value in a specified register

Here is the call graph for this function:

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

Reads the current value of conversion

Parameters

x	Returned x value
y	Returned y value
z	Returned z value

Here is the call graph for this function:

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

Gets the computed acceleration

Parameters

ax	Returned computed acceleration of the X-axis
ay	Returned computed acceleration of the Y-axis
az	Returned computed acceleration of the Z-axis

Here is the call graph for this function:

int getVerifiedAxis

(

MMA7660_REG_T

axis

)

Reads an axis, verifying its validity. The value passed must be one of REG_XOUT, REG_YOUT, or REG_ZOUT.

Parameters

axis	Axis to read

Returns

Axis value

Here is the call graph for this function:

uint8_t getVerifiedTilt

(

)

Reads the tilt register, verifying its validity

Returns

Tilt value

Here is the call graph for this function:

void setModeActive

(

)

Puts the device in the active mode. In this mode, register writes are not allowed. Place the device in the standby mode before attempting to write registers.

Here is the call graph for this function:

void setModeStandby

(

)

Puts the device in the standby (power saving) mode. Note: when in the standby mode, there is no valid data in the registers. In addition, the only way to write a register is to put the device in the standby mode.

Here is the call graph for this function:

uint8_t tiltBackFront

(

)

Reads tiltBackFront bits

The value returned is one of the MMA7660_TILT_BF_T values

Returns

Bits corresponding to the BackFront tilt status

Here is the call graph for this function:

uint8_t tiltLandscapePortrait

(

)

Reads tiltLandscapePortrait bits

The value returned is one of the MMA7660_TILT_LP_T values

Returns

Bits corresponding to the LandscapePortrait tilt status

Here is the call graph for this function:

bool tiltTap

(

)

Reads the tiltTap status

Returns

True if a tap is detected

Here is the call graph for this function:

bool tiltShake

(

)

Reads the tiltShake status

Returns

True if a shake is detected

Here is the call graph for this function:

void uninstallISR

(

)

Uninstalls the previously installed ISR

Here is the call graph for this function:

bool setInterruptBits

(

uint8_t

ibits

)

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

Parameters

ibits

Sets the requested interrupt bits

Returns

True if successful

Here is the call graph for this function:

bool setSampleRate

(

MMA7660_AUTOSLEEP_T

sr

)

Sets 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

Here is the call graph for this function:

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

Installs an interrupt service routine (ISR) to be called when an interrupt occurs

Parameters

pin	GPIO pin to use as the interrupt pin
isr	Pointer to a function to be called on interrupt
arg	Pointer to an object to be supplied as an argument to the ISR.

Here is the call graph for this function:

Collaboration diagram for MMA7660:

---

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

• src/mma7660/mma7660.hpp
• src/mma7660/mma7660.cxx