ICM-20948 Wake=on=Motion

Hi, I'm having trouble configuring the WOM logic for ICM-20948. The MPU9250 Product Specification has a flowchart explaining the necessary steps for configuring WOM, but the ICM-20948 is lacking in that regard. I've tried to translate the steps for MPU9250 to the ICM-20948, and this is the routine I'm using to set up:

    // Power down magnetometer

    bypassOn();

    m_i2c.writeByte(ICM20948_MAG_ADDRESS, ICM20948_RA_MAG_CNTL2, (uint8_t) MagMode::MAG_MODE_POWER_DOWN);

    bypassOff();
    selectBank(0);
    // Disable all interrupts

    writeByte(ICM20948_RA_INT_ENABLE, 0x00);

    writeByte(ICM20948_RA_INT_ENABLE_1, 0x00);

    writeByte(ICM20948_RA_INT_ENABLE_2, 0x00);
    // Set all CYCLE bits to 0

    writeByte(ICM20948_RA_LP_CONFIG, 0x00);

    

    // Set SLEEP to 0

    writeByte(ICM20948_RA_PWR_MGMT_1, 0x00);
    // Enable accel and disable gyro

    writeByte(ICM20948_RA_PWR_MGMT_2, 0x07);
    selectBank(2);
    // Configure accel LPF

    uint8_t accel_config = 0;

    accel_config |= ((uint8_t) AccelLpf::ADLPF_246_0Hz << 3);   // Set DLPF to 246.0 Hz

    // accel_config |= ((uint8_t) AccelRes::AFS_2G << 1);          // Set FSR to 2 g

    accel_config |= (1 << 0);                                   // Enable DLPF

    writeByte(ICM20948_RA_ACCEL_CONFIG, accel_config);
    // Enable motion interrupts only

    selectBank(0);

    writeByte(ICM20948_RA_INT_ENABLE, (1 << 3));
    selectBank(2);
    // Configure WOM logic

    writeByte(ICM20948_RA_ACCEL_INTEL_CTRL, 0x03);
    // Set the WOM threshold

    // LSB is 4mg. Available range is 0 - 1020mg (0-255 register value)

    threshold = (threshold > 1020) ? 1020 / 4 : threshold / 4;

    writeByte(ICM20948_RA_ACCEL_WOM_THR, threshold);
    // Set frequency of wake-up

    // uint8_t accel_smplrt_div = 1022;

    uint8_t accel_smplrt_div = 127;

    writeByte(ICM20948_RA_ACCEL_SMPLRT_DIV_1, ((accel_smplrt_div >> 8) & 0x0f));

    writeByte(ICM20948_RA_ACCEL_SMPLRT_DIV_2, (accel_smplrt_div & 0xff));
    selectBank(0);
    // Set LP_EN bit

    writeByte(ICM20948_RA_PWR_MGMT_1, (1 << 5));
    // Set ACCEL_CYCLE to 1 (Accel Low Power Mode)

    writeByte(ICM20948_RA_LP_CONFIG, (1 << 5));

The logic seems to work somewhat, but if I set the threshold below ~600 mg, the interrupt is triggered immediately after the configuration routine. If I set it above ~600 mg, the interrupt doesn't trigger, and if I tap the device hard on the table, the interrupt is triggered.

Are there any guidelines for configuring the WOM logic for ICM-20948?