Check configuration on lsm6dso32

[ms360]

Hi! 

I inherited a project and we're seeing strange accelerometer values and I'd like to get a sanity check on my configuration. when Idle and flat, I see 1g on Z, 0g on X and Y. When my device is moving I see peaks on many axes beyond 1g, eg 2.5 on X or Z, and it does not seem real. Here is downsampled data from a log file. X (brown) goes from +1.5g to -1.5g, Z (gray) is over 2.3g. I am not expecting such numbers during a short banked turn at ~15 mph 

This is my init. I'm expecting 104Hz data rate, 4g acc scale, 1000dps gyrp scale

	m_dev_ctx.write_reg = (stmdev_write_ptr) STWriteRegister;
	m_dev_ctx.read_reg = (stmdev_read_ptr) STReadRegister;

	lsm6dso32_reset_set(&m_dev_ctx, PROPERTY_ENABLE);

	do
	{
		lsm6dso32_reset_get(&m_dev_ctx, &rst);
	}
	while (rst);

	/* Enable Block Data Update */
	lsm6dso32_block_data_update_set(&m_dev_ctx, PROPERTY_ENABLE);

	/* Set Output Data Rate */
	lsm6dso32_xl_data_rate_set(&m_dev_ctx, LSM6DSO32_XL_ODR_104Hz_HIGH_PERF);
	lsm6dso32_gy_data_rate_set(&m_dev_ctx, LSM6DSO32_GY_ODR_104Hz_HIGH_PERF);
	// lsm6dso32_fifo_data_rate_set(&m_dev_ctx, lsm6dso32_GY_ODR_104Hz);

	/* Set full scale */
	lsm6dso32_xl_full_scale_set(&m_dev_ctx, LSM6DSO32_4g);
	lsm6dso32_gy_full_scale_set(&m_dev_ctx, LSM6DSO32_1000dps);

	lsm6dso32_timestamp_set(&m_dev_ctx, 1);

	//set watermark level to 2 samples
	lsm6dso32_fifo_watermark_set(&m_dev_ctx, 2);

	lsm6dso32_pin_int1_route_t int1_set = {};
	int1_set.int1_ctrl.int1_fifo_th = 1;
	results = lsm6dso32_pin_int1_route_set(&m_dev_ctx, &int1_set);

	uint8_t value = 0x44;//accell and gyro
	int ret = lsm6dso32_write_reg(&m_dev_ctx, LSM6DSO32_FIFO_CTRL3, &value, 1);

	uint8_t value = 0x06;
	int ret = lsm6dso32_write_reg(&m_dev_ctx, LSM6DSO32_FIFO_CTRL4, &value, 1); //ne

... skipping motion FX init b/c the raw accel data looks bad. 

 Data acquisition after INT1 -> process in app scheduler. Apologies for sloppy indenting. I didn't fix it yet. 

lsm6dso32_fifo_tag_t reg_tag;
    /* Read number of samples in FIFO */
    lsm6dso32_fifo_data_level_get(&m_dev_ctx, &num);
    int i=0;
    int t=0;
    // NRF_LOG_ERROR("IMU SAMPLES: %d",num);
    while (num--) {
        
        /* Read FIFO tag */
        lsm6dso32_fifo_sensor_tag_get(&m_dev_ctx, &reg_tag);
        uint8_t buffer[6];
        
        switch (reg_tag) {
            case LSM6DSO32_XL_NC_TAG:
            memset(&m_imu_raw_sample_buffer[i].m_raw_imu_values[3], 0x00, 3 * sizeof(int16_t));
            lsm6dso32_fifo_out_raw_get(&m_dev_ctx, (uint8_t *)&m_imu_raw_sample_buffer[i].m_raw_imu_values[3]);
            i++;
            break;
            
            case LSM6DSO32_GYRO_NC_TAG:
            memset(&m_imu_raw_sample_buffer[t].m_raw_imu_values[0], 0x00, 3 * sizeof(int16_t));
            lsm6dso32_fifo_out_raw_get(&m_dev_ctx, (uint8_t *)&m_imu_raw_sample_buffer[t].m_raw_imu_values[0]);
            t++;
            break;
            
            default:
            /* Flush unused samples */
            }
        }
        for (int y=0;y<i; y++)
        {
        IMU_Process_Data(&m_imu_raw_sample_buffer[y].m_raw_imu_values[3], &m_imu_raw_sample_buffer[y].m_raw_imu_values[0]);
        }
                

[Federica Bossi]

Hi @ms360 ,

We don't expect such values. Could you try repeating the test by implementing our examples available on GitHub? Just to exclude any issues related to your code.