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Hello everybody, First of all, thanks a lot for the Library, this saved me a lot of precious time! I'm here to ask for a little help : I'm using an Arduino Due (using arduino 1.5.5-r2 software) to read the data from my MPU6050, using the DMP. I read the angles using the same code as in the example code for the DMP and I tried a lot of different configurations, without any change. I noticed that reading the values takes my approximately 6ms. This is a little bit long for me, but the interesting thing is that the sketch spends 5ms of the 6 in the call of this function: // read a packet from FIFO mpu.getFIFOBytes(fifoBuffer, packetSize); I don't understand how this can be so long. This is just reading registers and the packetSize is only 42... So here are my questions. Is this normal with an MPU6050 or is there effectively something strange ? Does anybody have any idea why this is happening? When this function is called, the data should be ready, so why do I loose so much time ? I hope somebody will be able to help me with this, because otherwise I'll have to read the raw data and process them by myself. So thanks in advance for your answers!

Hi, I tried MPU_DMP6.ino and it compiles without error for UNO (haven’t tested on real board), but I am using DUE board and the sketch won’t compile for the arduino due board. Could you please tell me why I am getting this error, will be helpful. MPU6050_DMP6.ino: In function 'void setup()': MPU6050_DMP6:165: error: 'TWBR' was not declared in this scope If I put it as a comment then it compiles without error. but still dont know if it will actually work or not. Thank you.

Hi, I am using MPU6050 with your written code in DMP mode on Arduino due and it's working fine stand alone.. But I have to integrate some other things into my code like (Due timer library to generate software interrupt every second, external interrupt on pin 52 to count pulses ). when i tried to integrate them in one code i have FIFO Overflow problem. even though i tried to run it at as low as 20hz by changing the registers value in the "3dmath.h" file. can you please help me out with this problem i am facing. my project is kind of stuck at this point. Thank you. #include <DueTimer.h> #include "I2Cdev.h" #include "MPU6050_6Axis_MotionApps20.h" #if I2CDEV_IMPLEMENTATION == I2CDEV_ARDUINO_WIRE #include "Wire.h" #endif MPU6050 mpu; //#define OUTPUT_READABLE_WORLDACCEL #define OUTPUT_READABLE_REALACCEL #define LED_PIN 13 // (Arduino is 13, Teensy is 11, Teensy++ is 6) #define LED_PIN1 12 bool blinkState = false; bool blinkState1 = false; // MPU control/status vars bool dmpReady = false; // set true if DMP init was successful uint8_t mpuIntStatus; // holds actual interrupt status byte from MPU uint8_t devStatus; // return status after each device operation (0 = success, !0 = error) uint16_t packetSize; // expected DMP packet size (default is 42 bytes) uint16_t fifoCount; // count of all bytes currently in FIFO uint8_t fifoBuffer[64]; // FIFO storage buffer // orientation/motion vars Quaternion q; // [w, x, y, z] quaternion container VectorInt16 aa; // [x, y, z] accel sensor measurements VectorInt16 aaReal; // [x, y, z] gravity-free accel sensor measurements VectorInt16 aaWorld; // [x, y, z] world-frame accel sensor measurements VectorFloat gravity; // [x, y, z] gravity vector float euler[3]; // [psi, theta, phi] Euler angle container float ypr[3]; // [yaw, pitch, roll] yaw/pitch/roll container and gravity vector double vel_data; double vel; double Dummy = 0 ; double t_s = 0; double S[2] = {0,0}; double Q[2] = {0.05,0.05}; double R[2] = {0.5, 0.01}; double Y[2] = {0,0}; double X[2] ={0,0}; double P[2] = {0.5,0.5}; double K[2] = {0, 0}; uint32_t timer = 0; uint32_t dt = 0; int16_t sample,sped=0; int16_t ax, ay, az; int16_t gx, gy, gz; int16_t sensorValue; char val; int count; bool flag; // ================================================================ // === INTERRUPT DETECTION ROUTINE === // ================================================================ volatile bool mpuInterrupt = false; // indicates whether MPU interrupt pin has gone high void dmpDataReady() { mpuInterrupt = true; } // ================================================================ // === INITIAL SETUP === // ================================================================ void setup() { // join I2C bus (I2Cdev library doesn't do this automatically) #if I2CDEV_IMPLEMENTATION == I2CDEV_ARDUINO_WIRE Wire.begin(); Wire1.begin(); //TWBR = 24; // 400kHz I2C clock (200kHz if CPU is 8MHz) #elif I2CDEV_IMPLEMENTATION == I2CDEV_BUILTIN_FASTWIRE Fastwire::setup(400, true); #endif Serial1.begin(115200); //115200 or 19200 while (!Serial1); // wait for Leonardo enumeration, others continue immediately Serial1.println(F("Initializing I2C devices...")); mpu.initialize(); // verify connection Serial1.println(F("Testing device connections...")); Serial1.println(mpu.testConnection() ? F("MPU6050 connection successful") : F("MPU6050 connection failed")); // wait for ready // Serial1.println(F("\nSend any character to begin DMP programming and demo: ")); // while (Serial1.available() && Serial1.read()); // empty buffer // while (!Serial1.available()); // wait for data // while (Serial1.available() && Serial1.read()); // empty buffer again // load and configure the DMP Serial1.println(F("Initializing DMP...")); devStatus = mpu.dmpInitialize(); // supply your own gyro offsets here, scaled for min sensitivity mpu.setXGyroOffset(-1); //220 inc. will inc. mpu.setYGyroOffset(-24); //76 mpu.setZGyroOffset(51); //-85 mpu.setZAccelOffset(1788); // increasing number will increase 16384 // make sure it worked (returns 0 if so) if (devStatus == 0) { // turn on the DMP, now that it's ready Serial1.println(F("Enabling DMP...")); mpu.setDMPEnabled(true); // enable Arduino interrupt detection Serial1.println(F("Enabling interrupt detection (Arduino Due external interrupt 2)...")); attachInterrupt(2, dmpDataReady, RISING); mpuIntStatus = mpu.getIntStatus(); // set our DMP Ready flag so the main loop() function knows it's okay to use it Serial1.println(F("DMP ready! Waiting for first interrupt...")); dmpReady = true; // get expected DMP packet size for later comparison packetSize = mpu.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) Serial1.print(F("DMP Initialization failed (code ")); Serial1.print(devStatus); Serial1.println(F(")")); } // configure LED for output pinMode(LED_PIN, OUTPUT); delay(5000); attachInterrupt(52, rpm_fun, FALLING); Timer.getAvailable().attachInterrupt(firstHandler).start(1000000); // from DueTimer library delay(50); } void firstHandler(){ // Software interrupt every one second. Serial1.println("int"); flag = true; } void rpm_fun() // Hardware interrupt to count external pulses. { count = count + 1; } // ================================================================ // === MAIN PROGRAM LOOP === // ================================================================ void loop() { // if programming failed, don't try to do anything 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 = mpu.getIntStatus(); // get current FIFO count fifoCount = mpu.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 mpu.resetFIFO(); Serial1.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 = mpu.getFIFOCount(); // read a packet from FIFO mpu.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; #ifdef OUTPUT_READABLE_REALACCEL // display real acceleration, adjusted to remove gravity // -----Get data from MPU-6050----- mpu.dmpGetQuaternion(&q, fifoBuffer); mpu.dmpGetAccel(&aa, fifoBuffer); mpu.dmpGetGravity(&gravity, &q); mpu.dmpGetLinearAccel(&aaReal, &aa, &gravity); mpu.dmpGetYawPitchRoll(ypr, &q, &gravity); sample = -(aaReal.x); //Dummy = (abs(sample)>80) ? ((double)sample/16384)*9.81 : 0; Dummy = (double)sample/16384 * 9.81; t_s = (((double)micros() - timer)/1000000); // -----Get data from Arduino UNO----- Wire1.requestFrom(2, 1); // request 1 byte from slave device #2 while(Wire1.available()) // slave may send less than requested { sped = Wire1.read(); // receive a byte as character vel_data = ( 0.85 *((double)(sped)* 0.216)) + (0.15 * X[1]); // Serial1.println(sped); // print the character } //--------Prediction------- X[0] = X[0]; // Velocity X[1] = X[1]; // Acceleration P[0] = Q[0]; P[1] = t_s * Q[1]; //-------Kalman Gain-------- S[0] = P[0] + R[0]; S[1] = P[1] + R[1]; K[0] = P[0]/S[0]; K[1] = P[1]/S[1]; //--------Update------------- //vel = vel + t_s * Dummy; Y[0] = vel_data - X[0]; Y[1] = Dummy - X[1]; // Y[1] = Dummy - X[1]; X[0] = X[0] + (K[0]*Y[0]); X[1] = X[1] + (K[1]*Y[1]); P[0] = P[0] - (K[0]*P[0]); P[1] = P[1] - (K[1]*P[1]); timer = micros(); #endif // blink LED to indicate activity blinkState = !blinkState; digitalWrite(LED_PIN, blinkState); } }