mma8453 accelerometer - interrupt always active

[bergo]

Hey freescalers,

I'm using mma8453 accelerometer in a current project I'm working on.

I'm setting the interrupt INT 1 to be active low (once setting I can see in the oscilloscope that the INT 1 line is high).

As soon as I finish the rest of the configurations I detect an interrupt, and to clear the interrupt I read the register INT_SOURCE, but I read all 0's, ie. no interrupt to be handled.

looking at the oscilloscope I can see the INT 1 line is now low. and stays low.

I wonder what might be the cause for that and how can I force clean the interrupt line?

Thanks in advance,

[TomasVaverka · Accepted solution]

Bergo,

It would be fine to see your complete source code and schematic.

Anyway, the interrupts are deasserted by reading the appropriate status register for the embedded functions or reading the X, Y and Z data for the DRDY and FIFO.

Regards,

Tomas

[tramela]

Hi, 

I'm working with the same accelerometer (MMA8453) and i'm expecting exactly the same issue. I already tried a simple code where i'm reading the accelerometer values every time a flag is triggered in the interruption. After it I read the interruption register to clean the interrupt flag. After some time working, my accelerometer stops working and, using a digital analizer, I saw it was the interruption pin that was blocked in low. 

 
Here is some parts of the code where you can see how it was implemented. I already tried to enable the Transient mode but stills not working properly. 

``` 

/**  * configure  * @brief Accelerometer configuration.  *          To configure the MMA8453 set it to Standby mode, perform the  *          modifications and change it back to Active mode.  *  *  @param none  *  *  @return none  *  */ void CMMA8453::configure() {  /* MMA8453 configuration for Data Ready mode */
 /* Set the module in standby mode to configure it */
 this->sleep();

 /* Set full-scale range to 2G */
 this->writeByte(REG_XYZ_DATA_CFG_ADDRESS, REG_RANGE_2G_VALUE);

 /* Configure Transient */
 this->writeByte(REG_TRANSIENT_CFG_ADDRESS, REG_TRANSIENT_ELE_VALUE);

 /* Data Ready mode */
 this->writeByte(REG_CTRL_REG2_ADDRESS, REG_CTRL_REG2_NORMAL_MODE_VALUE);
 /* Set open drain on interrupt pad */
 this->writeByte(REG_CTRL_REG3_ADDRESS, REG_CTRL_REG3_OPEN_DRAIN_WAKE_TRANSIENT_VALUE);
 /* Enable data ready interrupt */
 this->writeByte(REG_CTRL_REG4_ADDRESS, REG_CTRL_REG4_DATA_READY_TRANSIENT_INT_EN_VALUE);
 /* Route interrupt to INT1 pin */
 this->writeByte(REG_CTRL_REG5_ADDRESS, REG_CTRL_REG5_DATA_READY_INT2_VALUE);

 /* Set the module in active mode to start collecting data */
 this->wakeUp(); }

/**
 * hasNewData
 * @brief Check if new accelerometer data is available
 *
 * @param none
 *
 * @return true if new data is available
 * false if new data is not available
 *
 **/
bool
CMMA8453::hasNewData()
{
 /* Request interrupt source */
 uint8_t interruptSource = 0;
 uint8_t interruptTransient = 0;

 if (true == this->has_interrupt_occured ) {

 /* Clear interrupt flags*/
 this->readByte(REG_TRANSIENT_SRC_ADDRESS, &interruptTransient);
 this->readByte(REG_INT_SOURCE_ADDRESS, &interruptSource);

 /* Handle interrupt data is ready */
 if ((interruptSource & REG_SRC_DATA_READY_VALUE) == REG_SRC_DATA_READY_VALUE) {
 /* Signal that new data is available */
 return true;
 }
 }
 return false;

}


/**
 * sleep
 * @brief Put the accelerometer in standby mode
 *
 * @param none
 *
 * @return none
 *
 **/
void
CMMA8453::sleep()
{
 /* Set output data rate (ODR) to 6.25Hz and Standby mode */
 this->writeByte(REG_CTRL_REG1_ADDRESS, (REG_CTRL_REG1_6Hz_VALUE | REG_CTRL_REG1_STANDBY_VALUE));
}


/**
 * wakeUp
 * @brief Put the accelerometer in active mode
 *
 * @param none
 *
 * @return none
 *
 **/
void
CMMA8453::wakeUp()
{
 /* Set output data rate (ODR) to 6.25Hz and Active mode */
 this->writeByte(REG_CTRL_REG1_ADDRESS, (REG_CTRL_REG1_6Hz_VALUE | REG_CTRL_REG1_ACTIVE_VALUE));
}


/**
 * interruptHandler
 * @brief Handles the Interrupt by checking the interrupt source
 * and acts accordingly.
 *
 * @param none
 *
 * @return none
 *
 **/
void
CMMA8453::interruptHandler()
{
 /* Disable Interrupt */
 nrf_drv_gpiote_in_event_disable(CGPIO::INT1_ACC);

 this->has_interrupt_occured = true;

 /* Enable Interrupt */
 nrf_drv_gpiote_in_event_enable(CGPIO::INT1_ACC, true);
}

[tramela]

I forgot to send the defines:

MMA8453_ADDRESS = 0x1C;

REG_CTRL_REG1_ADDRESS = 0x2A;
REG_CTRL_REG2_ADDRESS = 0x2B;
REG_CTRL_REG3_ADDRESS = 0x2C;
REG_CTRL_REG4_ADDRESS = 0x2D;
REG_CTRL_REG5_ADDRESS = 0x2E;

REG_CTRL_REG1_6Hz_VALUE = 0x30;
REG_CTRL_REG2_NORMAL_MODE_VALUE = 0x00;

REG_CTRL_REG3_OPEN_DRAIN_WAKE_TRANSIENT_VALUE = 0x41;

REG_CTRL_REG4_DATA_READY_TRANSIENT_INT_EN_VALUE = 0x01;

REG_CTRL_REG5_ALL_INT_ROUTED_INT1_VALUE = 0xBD;

REG_TRANSIENT_CFG_ADDRESS = 0x1D;

REG_TRANSIENT_SRC_ADDRESS = 0x1E;

REG_INT_SOURCE_ADDRESS = 0x0C

REG_SRC_DATA_READY_VALUE = 0x01;

Regards