InvenSense DMP and MPL porting problem, data ready interrupt not working

[YooLoo]

Hello everyone,

I am currently working on porting the InvenSense motion driver 6.12 to nrf52.

I am using MPU9250 and nrf52840 pdk.

I've managed to set up the DMP and MPL, but I got stuck when I trying to read data from DMP FIFO.

I am instructed to call function dmp_read_fifo whenever a data ready interrupt is detected. I connected pin INT of MPU to P1.08 of nrf52840pdk.

Here is how I set up the interrupt:

#define ARDUINO_7_PIN               NRF_GPIO_PIN_MAP(1, 8)
#define PIN_IN ARDUINO_7_PIN 

static void pin_in_read(nrf_drv_gpiote_pin_t pin, nrf_gpiote_polarity_t action)
{
		hal.new_gyro = 1; //set data ready indicator
}

static void GPIO_setup()
{
	uint32_t err_code = nrf_drv_gpiote_init();
	APP_ERROR_CHECK(err_code);
	
    nrf_drv_gpiote_in_config_t in_config = GPIOTE_CONFIG_IN_SENSE_TOGGLE(true);
    in_config.pull = NRF_GPIO_PIN_PULLUP;
	
	err_code = nrf_drv_gpiote_in_init(PIN_IN, &in_config, pin_in_read);
    APP_ERROR_CHECK(err_code);			
}

However hal.new_gyro is never set. Does anyone meet the same problem?

My project can be found here.

Thanks in advance.

[MartinBL]

Have you remembered to enable your GPIOTE channel with nrf_drv_gpiote_in_event_enable()?

[YooLoo]

Hello Martin,

Yes you are right, I did forget nrf_drv_gpiote_in_event_enable() ! Thank you very much. However, after I fixed this error, I met another problem:

The code works fine at first, then after a short random time, dmp_read_fifo() and mpu_get_compass_reg() fails.

dmp_read_fifo returns an error code -1, which is caused by the function mpu_read_fifo_stream(). This function returns an error code -3, which is caused by the failure of function i2c_read;

mpu_get_compass_reg returns an error code -4, which is also caused by the failure of function i2c_read;

Here is my i2c_read function:

uint32_t mpu_twi_read_test(uint8_t slave_addr,
											uint8_t reg_addr,
											uint32_t length,
											uint8_t *data)
{
	  uint32_t err_code;
		uint32_t timeout = MPU_TWI_TIMEOUT;
	
	  err_code = nrf_drv_twi_tx(&m_twi_instance, slave_addr, &reg_addr, 1, false);
		if(err_code != NRF_SUCCESS) return err_code;

    while((!twi_tx_done) && --timeout);
    if(!timeout) return NRF_ERROR_TIMEOUT;
    twi_tx_done = false;	
	
	  err_code = nrf_drv_twi_rx(&m_twi_instance, slave_addr, data, length);
    if(err_code != NRF_SUCCESS) return err_code;
		
		timeout = MPU_TWI_TIMEOUT;
    while((!twi_rx_done) && --timeout);
    if(!timeout) return NRF_ERROR_TIMEOUT;
    twi_rx_done = false;
	
		return err_code;
}

Could you pls have a look what might cause this problem? I've updated my code on Github. Many thanks!

[YooLoo]

Hello Martin, due to the schedule I have to work on the other part of my project in the previous two months. Now I think I've figured out what causes the NER_ERROR_BUSY. I am using NRF_LOG_RAW_INFO to print data to uart. This error will happen when NRF_LOG_FLUSH() is called while the deferred log buffer is too long. So is there any more efficient way to print out float data other than NRF_LOG_RAW_INFO?

[Nguyen Hoan Hoang]

Would be better to directly print it via uart.  Add retarget.c then you can use the standard printf over uart.

[YooLoo]

Thank you for advice! I've fixed my problem now.

[achandran]

YooLoo, I am trying to do a similar project and am getting hung up on integrating the dmp code. The link you have on the first post is not valid, is there an updated link where I can look at your code?

[YooLoo]

Hello, the link should be available now. Sorry for the delay, hope it still could help you.