在ucos中想采集MPU6050数据有问题--（mpu_dmp_get_data）返回值是1，而不是0

jingxc

如果正常的的话应该return 0,我是在ucos中使用的，结果下面这个函数返回值是非0，可能是什么原因出错

dmp_read_fifo(short *gyro, short *accel, long *quat,
    unsigned long *timestamp, short *sensors, unsigned char *more)
{
    unsigned char fifo_data[MAX_PACKET_LENGTH];
    unsigned char ii = 0;
    /* TODO: sensors[0] only changes when dmp_enable_feature is called. We can
     * cache this value and save some cycles.
     */
    sensors[0] = 0;
    /* Get a packet. */
    if (mpu_read_fifo_stream(dmp.packet_length, fifo_data, more))
        return -1;
    /* Parse DMP packet. */
    if (dmp.feature_mask & (DMP_FEATURE_LP_QUAT | DMP_FEATURE_6X_LP_QUAT)) {
#ifdef FIFO_CORRUPTION_CHECK
        long quat_q14[4], quat_mag_sq;
#endif
        quat[0] = ((long)fifo_data[0] << 24) | ((long)fifo_data[1] << 16) |
            ((long)fifo_data[2] << 8) | fifo_data[3];
        quat[1] = ((long)fifo_data[4] << 24) | ((long)fifo_data[5] << 16) |
            ((long)fifo_data[6] << 8) | fifo_data[7];
        quat[2] = ((long)fifo_data[8] << 24) | ((long)fifo_data[9] << 16) |
            ((long)fifo_data[10] << 8) | fifo_data[11];
        quat[3] = ((long)fifo_data[12] << 24) | ((long)fifo_data[13] << 16) |
            ((long)fifo_data[14] << 8) | fifo_data[15];
        ii += 16;
#ifdef FIFO_CORRUPTION_CHECK
        /* We can detect a corrupted FIFO by monitoring the quaternion data and
         * ensuring that the magnitude is always normalized to one. This
         * shouldn't happen in normal operation, but if an I2C error occurs,
         * the FIFO reads might become misaligned.
         *
         * Let's start by scaling down the quaternion data to avoid long long
         * math.
         */
        quat_q14[0] = quat[0] >> 16;
        quat_q14[1] = quat[1] >> 16;
        quat_q14[2] = quat[2] >> 16;
        quat_q14[3] = quat[3] >> 16;
        quat_mag_sq = quat_q14[0] * quat_q14[0] + quat_q14[1] * quat_q14[1] +
            quat_q14[2] * quat_q14[2] + quat_q14[3] * quat_q14[3];
        if ((quat_mag_sq < QUAT_MAG_SQ_MIN) ||
            (quat_mag_sq > QUAT_MAG_SQ_MAX)) {
            /* Quaternion is outside of the acceptable threshold. */
            mpu_reset_fifo();
            sensors[0] = 0;
            return -1;
        }
        sensors[0] |= INV_WXYZ_QUAT;
#endif
    }
    if (dmp.feature_mask & DMP_FEATURE_SEND_RAW_ACCEL) {
        accel[0] = ((short)fifo_data[ii+0] << 8) | fifo_data[ii+1];
        accel[1] = ((short)fifo_data[ii+2] << 8) | fifo_data[ii+3];
        accel[2] = ((short)fifo_data[ii+4] << 8) | fifo_data[ii+5];
        ii += 6;
        sensors[0] |= INV_XYZ_ACCEL;
    }
    if (dmp.feature_mask & DMP_FEATURE_SEND_ANY_GYRO) {
        gyro[0] = ((short)fifo_data[ii+0] << 8) | fifo_data[ii+1];
        gyro[1] = ((short)fifo_data[ii+2] << 8) | fifo_data[ii+3];
        gyro[2] = ((short)fifo_data[ii+4] << 8) | fifo_data[ii+5];
        ii += 6;
        sensors[0] |= INV_XYZ_GYRO;
    }
    /* Gesture data is at the end of the DMP packet. Parse it and call
     * the gesture callbacks (if registered).
     */
    if (dmp.feature_mask & (DMP_FEATURE_TAP | DMP_FEATURE_ANDROID_ORIENT))
        decode_gesture(fifo_data + ii);
    get_ms(timestamp);
    return 0;
}