Use DMP of MPU9250

Question

my code is below.
 git_mpu9250_dmp.zip 
 Hello. 
 I use nRF52 & MPU9250.
I want to use DMP,
but I can't read data with DMP.
Because it have failed that writting firmware. 
 I want to check connect sensor between nRF,
I made a code for reading register of "WHO_AM_I".
At first time, read "WHO_AM_I", return 0x71.
After faild writting firmware, read "WHO_AM_I",return 0x0d. 
 I wrote firmware below,
16,0,0,70,0,0,0,0,24,0,0,0,2,0,3,0,0...
read mem below,
0,83,5a,44,9,46,10,6,0,0,15,bb,48,79,c1,3c... 
 What was happened?

Sagisawa Yukichi · Accepted Answer

I thought again, I solved this problem. This problem was mistake resister to be written.

Thank you for the advice,it was very helpful!!

    if ((errCode = mpu_write_mem(ii, this_write, progBuffer))) {
					free(progBuffer);
        return -3;
    }
    
    if (mpu_read_mem(ii, this_write, cur)){
					free(progBuffer);
        return -4;
			}
        
    if (memcmp(progBuffer, cur, this_write)) {
				printf("this_write = %d \r\n",this_write);
				for (int i = 0; i < this_write ; i++){
				  printf("progBuffer = %x , cur = %x\r\n",progBuffer[i],cur[i]);
				}
				free(progBuffer);
      return -5;
    }

Additional note @2017/05/22

I don't know necessary 2 i2c_write.

#define i2c_write_one call_mpu9250_write_m
#define i2c_write call_mpu9250_write

static uint32_t mpu9250_write(uint8_t address, uint8_t reg, uint32_t length, uint8_t const * p_data)
{
    uint32_t err_code;
	
		for(uint8_t i = 0; i < length ; i++){
			
			uint8_t packet[2] = {(reg+i), p_data[i]};
#ifdef PTEST
			printf("calledw #2\r\n");

				nrf_delay_ms(10);
			printf("%d,%d,%d\r\n",address,packet[0],packet[1]);
	
#endif
			err_code = nrf_drv_twi_tx(&m_twi_instance, address, packet, 2, false);
			if(err_code != NRF_SUCCESS) {
				printf("mpu9250_write error %d\r\n",err_code);
				nrf_delay_ms(50);
				
			  return err_code;
			}
			 #ifdef PTEST
			printf(" timer ");
			//	nrf_delay_ms(10);
			#endif
			
			if(!waitInt(MPU9250_TWI_TIMEOUT)){
					printf(" timeout...w ");
					nrf_delay_ms(10);
					return NRF_ERROR_TIMEOUT;
			}
			twi_done = false;
	
		}
			
			#ifdef PTEST
		printf("write_end! %d\r\n",err_code);
				nrf_delay_ms(10);
			#endif
    return err_code;
}


uint32_t call_mpu9250_write(uint8_t address, uint8_t reg, uint32_t length, uint8_t const * p_data){
		return mpu9250_write(address, reg, length , p_data);
}

static uint32_t mpu9250_write_m(uint8_t address, uint8_t reg, uint32_t length, uint8_t const * p_data)
{
    uint32_t err_code;
	for(uint8_t i = 0; i < length ; i++){
		uint8_t packet[2] = {(reg), p_data[i]}; //write to same regster

#ifdef PTEST
		printf("calledwm #2\r\n");
		nrf_delay_ms(10);
		printf("%d,%d,%d\r\n",address,packet[0],packet[1]);
	    nrf_delay_ms(10);
#endif
			
		err_code = nrf_drv_twi_tx(&m_twi_instance, address, packet, 2, false);

#ifdef PTEST
		printf("end nrf_drv_twi_tx\r\n");
		nrf_delay_ms(10);
#endif			
			
		if(err_code != NRF_SUCCESS) {
			printf("mpu9250_write error %d\r\n",err_code);
			nrf_delay_ms(50);
			return err_code;
		}
			
#ifdef PTEST
		printf(" timer ");
		nrf_delay_ms(10);
#endif
			
		if(!waitInt(MPU9250_TWI_TIMEOUT)){ //if waitInt() return true,then twi is done.
			printf(" timeout...wm ");
			nrf_delay_ms(10);
			return NRF_ERROR_TIMEOUT;
		}
			
		twi_done = false;
	}
		
#ifdef PTEST
	printf("write_m_end! %d\r\n",err_code);
	nrf_delay_ms(10);
	#endif
   return err_code;
}

uint32_t call_mpu9250_write_m(uint8_t address, uint8_t reg, uint32_t length, uint8_t const * p_data){
		return mpu9250_write_m(address, reg, length , p_data);
}

int mpu_write_mem(unsigned short mem_addr, unsigned short length,
        unsigned char *data)
{
    unsigned char tmp[2];

    if (!data)
        return -1;
    if (!st->chip_cfg.sensors)
        return -2;

//		printf("sensors = %d\r\n",st->chip_cfg.sensors);
		
    tmp[0] = (unsigned char)(mem_addr >> 8);
    tmp[1] = (unsigned char)(mem_addr & 0xFF);

    /* Check bank boundaries. */
    if (tmp[0] + length > st->hw->bank_size)
        return -3;

    if (i2c_write(st->hw->addr, st->reg->bank_sel, 2, tmp))
        return -4;
    if (i2c_write_one(st->hw->addr, st->reg->mem_r_w, length, data))
        return -5;
    return 0;
}

Use DMP of MPU9250

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