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Weather station + MPU6050

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Hi to all!


I am using the MPU-6050 sensor, among others, as a part of my graduation project.

I am trying to use the MPU6050 together with the BMP180 (and some other simpler sensors), and with some intuition I could manage to make them work together by just taking the raw data from the MPU6050. All my attempts to use the needed libraries to acquire the yaw/pitch/roll data format and take into account the DMP and the fifo buffer the sensor itself has while using other sensors in the same program have failed, maybe because I don't have so much experience with programming. I attach my code, because maybe you could help me to make it work. The MPU6050 example works, as far as I don't mix it with other sensors.


I use different functions as part of the main code, like these ones:



void initMPU6050()
    // initialize MPU6050
    Serial.println(accelgyro.testConnection() ? "MPU6050 connection successful" : "MPU6050 connection failed");


void readAccelgyro()


    int16_t ax, ay, az;
    int16_t gx, gy, gz;
    accelgyro.getMotion6(&ax, &ay, &az, &gx, &gy, &gz);
    if (!dmpReady) return;
    // wait for MPU interrupt or extra packet(s) available
    while (!mpuInterrupt && fifoCount < packetSize) {
        // other program behavior stuff here
        // .
        // .
        // .
        // if you are really paranoid you can frequently test in between other
        // stuff to see if mpuInterrupt is true, and if so, "break;" from the
        // while() loop to immediately process the MPU data
        // .
        // .
        // .
    // reset interrupt flag and get INT_STATUS byte
    mpuInterrupt = false;
    mpuIntStatus = accelgyro.getIntStatus();
    // get current FIFO count
    fifoCount = accelgyro.getFIFOCount();
    // check for overflow (this should never happen unless our code is too inefficient)
    if ((mpuIntStatus & 0x10) || fifoCount == 1024) {
        // reset so we can continue cleanly
        Serial.println(F("FIFO overflow!"));
    // otherwise, check for DMP data ready interrupt (this should happen frequently)
    } else if (mpuIntStatus & 0x02) {
        // wait for correct available data length, should be a VERY short wait
        while (fifoCount < packetSize) fifoCount = accelgyro.getFIFOCount();
        // read a packet from FIFO
        accelgyro.getFIFOBytes(fifoBuffer, packetSize);
        // track FIFO count here in case there is > 1 packet available
        // (this lets us immediately read more without waiting for an interrupt)
        fifoCount -= packetSize;
        accelgyro.dmpGetQuaternion(&q, fifoBuffer);
        accelgyro.dmpGetGravity(&gravity, &q);
        accelgyro.dmpGetYawPitchRoll(ypr, &q, &gravity);}
    //store data
    data.ax = ax;
    data.ay = ay;
    data.az = az;
    data.gx = gx;
    data.gy = gy;
    data.gz = gz;
    data.yaw =  ypr[0] * 180/M_PI;
    data.pitch = ypr[1] * 180/M_PI;
    data.roll = ypr[2] * 180/M_PI;



But all I get from the ypr variables are zeros.


Any help would be really appreciated.

Kind regards,




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Here's an update: I've changed one of the functions:



void initMPU6050()

    // initialize MPU6050
    Serial.println(accelgyro.testConnection() ? "MPU6050 connection successful" : "MPU6050 connection failed");
    devStatus = accelgyro.dmpInitialize();
    // make sure it worked (returns 0 if so)
    if (devStatus == 0) {
        // turn on the DMP, now that it's ready
        Serial.println(F("Enabling DMP..."));
        // enable Arduino interrupt detection
        Serial.println(F("Enabling interrupt detection (Arduino external interrupt 0)..."));
        attachInterrupt(0, dmpDataReady, RISING);
        mpuIntStatus = accelgyro.getIntStatus();
        // set our DMP Ready flag so the main loop() function knows it's okay to use it
        Serial.println(F("DMP ready! Waiting for first interrupt..."));
        dmpReady = true;
        // get expected DMP packet size for later comparison
        packetSize = accelgyro.dmpGetFIFOPacketSize();
    } else {
        // ERROR!
        // 1 = initial memory load failed
        // 2 = DMP configuration updates failed
        // (if it's going to break, usually the code will be 1)
        Serial.print(F("DMP Initialization failed (code "));



But now the yaw doesn't work. There's almost no variation when I move the breadboard where the MPU is. Any thoughts at all?

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