+// 6 axis gyro demo
+// Beware: this does not work on old Uno, requires a r3.
+
+// I2C device class (I2Cdev) demonstration Arduino sketch for MPU6050 class using DMP (MotionApps v2.0)
+// 6/21/2012 by Jeff Rowberg <jeff@rowberg.net>
+// Updates should (hopefully) always be available at https://github.com/jrowberg/i2cdevlib
+//
+// Changelog:
+// 2013-05-08 - added seamless Fastwire support
+// - added note about gyro calibration
+// 2012-06-21 - added note about Arduino 1.0.1 + Leonardo compatibility error
+// 2012-06-20 - improved FIFO overflow handling and simplified read process
+// 2012-06-19 - completely rearranged DMP initialization code and simplification
+// 2012-06-13 - pull gyro and accel data from FIFO packet instead of reading directly
+// 2012-06-09 - fix broken FIFO read sequence and change interrupt detection to RISING
+// 2012-06-05 - add gravity-compensated initial reference frame acceleration output
+// - add 3D math helper file to DMP6 example sketch
+// - add Euler output and Yaw/Pitch/Roll output formats
+// 2012-06-04 - remove accel offset clearing for better results (thanks Sungon Lee)
+// 2012-06-01 - fixed gyro sensitivity to be 2000 deg/sec instead of 250
+// 2012-05-30 - basic DMP initialization working
+
+/* ============================================
+I2Cdev device library code is placed under the MIT license
+Copyright (c) 2012 Jeff Rowberg
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+===============================================
+*/
+
+// I2Cdev and MPU6050 must be installed as libraries, or else the .cpp/.h files
+// for both classes must be in the include path of your project
+#include "I2Cdev.h"
+
+#include "MPU6050_6Axis_MotionApps20.h"
+//#include "MPU6050.h" // not necessary if using MotionApps include file
+
+// Arduino Wire library is required if I2Cdev I2CDEV_ARDUINO_WIRE implementation
+// is used in I2Cdev.h
+#if I2CDEV_IMPLEMENTATION == I2CDEV_ARDUINO_WIRE
+ #include "Wire.h"
+#endif
+
+// class default I2C address is 0x68
+// specific I2C addresses may be passed as a parameter here
+// AD0 low = 0x68 (default for SparkFun breakout and InvenSense evaluation board)
+// AD0 high = 0x69
+MPU6050 mpu;
+//MPU6050 mpu(0x69); // <-- use for AD0 high
+
+/* =========================================================================
+ NOTE: In addition to connection 3.3v, GND, SDA, and SCL, this sketch
+ depends on the MPU-6050's INT pin being connected to the Arduino's
+ external interrupt #0 pin. On the Arduino Uno and Mega 2560, this is
+ digital I/O pin 2.
+ * ========================================================================= */
+
+/* =========================================================================
+ NOTE: Arduino v1.0.1 with the Leonardo board generates a compile error
+ when using Serial.write(buf, len). The Teapot output uses this method.
+ The solution requires a modification to the Arduino USBAPI.h file, which
+ is fortunately simple, but annoying. This will be fixed in the next IDE
+ release. For more info, see these links:
+
+ http://arduino.cc/forum/index.php/topic,109987.0.html
+ http://code.google.com/p/arduino/issues/detail?id=958
+ * ========================================================================= */
+
+
+
+// uncomment "OUTPUT_READABLE_QUATERNION" if you want to see the actual
+// quaternion components in a [w, x, y, z] format (not best for parsing
+// on a remote host such as Processing or something though)
+//#define OUTPUT_READABLE_QUATERNION
+
+// uncomment "OUTPUT_READABLE_EULER" if you want to see Euler angles
+// (in degrees) calculated from the quaternions coming from the FIFO.
+// Note that Euler angles suffer from gimbal lock (for more info, see
+// http://en.wikipedia.org/wiki/Gimbal_lock)
+//#define OUTPUT_READABLE_EULER
+
+// uncomment "OUTPUT_READABLE_YAWPITCHROLL" if you want to see the yaw/
+// pitch/roll angles (in degrees) calculated from the quaternions coming
+// from the FIFO. Note this also requires gravity vector calculations.
+// Also note that yaw/pitch/roll angles suffer from gimbal lock (for
+// more info, see: http://en.wikipedia.org/wiki/Gimbal_lock)
+#define OUTPUT_READABLE_YAWPITCHROLL
+
+// uncomment "OUTPUT_READABLE_REALACCEL" if you want to see acceleration
+// components with gravity removed. This acceleration reference frame is
+// not compensated for orientation, so +X is always +X according to the
+// sensor, just without the effects of gravity. If you want acceleration
+// compensated for orientation, us OUTPUT_READABLE_WORLDACCEL instead.
+//#define OUTPUT_READABLE_REALACCEL
+
+// uncomment "OUTPUT_READABLE_WORLDACCEL" if you want to see acceleration
+// components with gravity removed and adjusted for the world frame of
+// reference (yaw is relative to initial orientation, since no magnetometer
+// is present in this case). Could be quite handy in some cases.
+//#define OUTPUT_READABLE_WORLDACCEL
+
+// uncomment "OUTPUT_TEAPOT" if you want output that matches the
+// format used for the InvenSense teapot demo
+//#define OUTPUT_TEAPOT
+
+
+
+#define LED_PIN 13 // (Arduino is 13, Teensy is 11, Teensy++ is 6)
+bool blinkState = 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
+
+// packet structure for InvenSense teapot demo
+uint8_t teapotPacket[14] = { '$', 0x02, 0,0, 0,0, 0,0, 0,0, 0x00, 0x00, '\r', '\n' };
+
+
+
+// ================================================================
+// === 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();
+ TWBR = 24; // 400kHz I2C clock (200kHz if CPU is 8MHz)
+ #elif I2CDEV_IMPLEMENTATION == I2CDEV_BUILTIN_FASTWIRE
+ Fastwire::setup(400, true);
+ #endif
+
+ // initialize serial communication
+ // (115200 chosen because it is required for Teapot Demo output, but it's
+ // really up to you depending on your project)
+ Serial.begin(115200);
+ while (!Serial); // wait for Leonardo enumeration, others continue immediately
+
+ // NOTE: 8MHz or slower host processors, like the Teensy @ 3.3v or Ardunio
+ // Pro Mini running at 3.3v, cannot handle this baud rate reliably due to
+ // the baud timing being too misaligned with processor ticks. You must use
+ // 38400 or slower in these cases, or use some kind of external separate
+ // crystal solution for the UART timer.
+
+ // initialize device
+ Serial.println(F("Initializing I2C devices..."));
+ mpu.initialize();
+
+ // verify connection
+ Serial.println(F("Testing device connections..."));
+ Serial.println(mpu.testConnection() ? F("MPU6050 connection successful") : F("MPU6050 connection failed"));
+
+ // wait for ready
+ Serial.println(F("\nSend any character to begin DMP programming and demo: "));
+ while (Serial.available() && Serial.read()); // empty buffer
+ while (!Serial.available()); // wait for data
+ while (Serial.available() && Serial.read()); // empty buffer again
+
+ // load and configure the DMP
+ Serial.println(F("Initializing DMP..."));
+ devStatus = mpu.dmpInitialize();
+
+ // supply your own gyro offsets here, scaled for min sensitivity
+ mpu.setXGyroOffset(220);
+ mpu.setYGyroOffset(76);
+ mpu.setZGyroOffset(-85);
+ mpu.setZAccelOffset(1788); // 1688 factory default for my test chip
+
+ // 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..."));
+ mpu.setDMPEnabled(true);
+
+ // enable Arduino interrupt detection
+ Serial.println(F("Enabling interrupt detection (Arduino external interrupt 0)..."));
+ attachInterrupt(0, dmpDataReady, RISING);
+ mpuIntStatus = mpu.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 = 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)
+ Serial.print(F("DMP Initialization failed (code "));
+ Serial.print(devStatus);
+ Serial.println(F(")"));
+ }
+
+ // configure LED for output
+ pinMode(LED_PIN, OUTPUT);
+}
+
+
+
+// ================================================================
+// === 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();
+ 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 = 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_QUATERNION
+ // display quaternion values in easy matrix form: w x y z
+ mpu.dmpGetQuaternion(&q, fifoBuffer);
+ Serial.print("quat\t");
+ Serial.print(q.w);
+ Serial.print("\t");
+ Serial.print(q.x);
+ Serial.print("\t");
+ Serial.print(q.y);
+ Serial.print("\t");
+ Serial.println(q.z);
+ #endif
+
+ #ifdef OUTPUT_READABLE_EULER
+ // display Euler angles in degrees
+ mpu.dmpGetQuaternion(&q, fifoBuffer);
+ mpu.dmpGetEuler(euler, &q);
+ Serial.print("euler\t");
+ Serial.print(euler[0] * 180/M_PI);
+ Serial.print("\t");
+ Serial.print(euler[1] * 180/M_PI);
+ Serial.print("\t");
+ Serial.println(euler[2] * 180/M_PI);
+ #endif
+
+ #ifdef OUTPUT_READABLE_YAWPITCHROLL
+ // display Euler angles in degrees
+ mpu.dmpGetQuaternion(&q, fifoBuffer);
+ mpu.dmpGetGravity(&gravity, &q);
+ mpu.dmpGetYawPitchRoll(ypr, &q, &gravity);
+ Serial.print("ypr\t");
+ Serial.print(ypr[0] * 180/M_PI);
+ Serial.print("\t");
+ Serial.print(ypr[1] * 180/M_PI);
+ Serial.print("\t");
+ Serial.println(ypr[2] * 180/M_PI);
+ #endif
+
+ #ifdef OUTPUT_READABLE_REALACCEL
+ // display real acceleration, adjusted to remove gravity
+ mpu.dmpGetQuaternion(&q, fifoBuffer);
+ mpu.dmpGetAccel(&aa, fifoBuffer);
+ mpu.dmpGetGravity(&gravity, &q);
+ mpu.dmpGetLinearAccel(&aaReal, &aa, &gravity);
+ Serial.print("areal\t");
+ Serial.print(aaReal.x);
+ Serial.print("\t");
+ Serial.print(aaReal.y);
+ Serial.print("\t");
+ Serial.println(aaReal.z);
+ #endif
+
+ #ifdef OUTPUT_READABLE_WORLDACCEL
+ // display initial world-frame acceleration, adjusted to remove gravity
+ // and rotated based on known orientation from quaternion
+ mpu.dmpGetQuaternion(&q, fifoBuffer);
+ mpu.dmpGetAccel(&aa, fifoBuffer);
+ mpu.dmpGetGravity(&gravity, &q);
+ mpu.dmpGetLinearAccel(&aaReal, &aa, &gravity);
+ mpu.dmpGetLinearAccelInWorld(&aaWorld, &aaReal, &q);
+ Serial.print("aworld\t");
+ Serial.print(aaWorld.x);
+ Serial.print("\t");
+ Serial.print(aaWorld.y);
+ Serial.print("\t");
+ Serial.println(aaWorld.z);
+ #endif
+
+ #ifdef OUTPUT_TEAPOT
+ // display quaternion values in InvenSense Teapot demo format:
+ teapotPacket[2] = fifoBuffer[0];
+ teapotPacket[3] = fifoBuffer[1];
+ teapotPacket[4] = fifoBuffer[4];
+ teapotPacket[5] = fifoBuffer[5];
+ teapotPacket[6] = fifoBuffer[8];
+ teapotPacket[7] = fifoBuffer[9];
+ teapotPacket[8] = fifoBuffer[12];
+ teapotPacket[9] = fifoBuffer[13];
+ Serial.write(teapotPacket, 14);
+ teapotPacket[11]++; // packetCount, loops at 0xFF on purpose
+ #endif
+
+ // blink LED to indicate activity
+ blinkState = !blinkState;
+ digitalWrite(LED_PIN, blinkState);
+ }
+}