Pam,
Thank you so much for your kind help. I am very new to programming and actually haven't done any coding from scratch. I hope you don't mind I shoot some questions about the code you posted. It seems to me that this excerpt of code is similar to DMP6 running code. As you mentioned, you don't use the interrupt part of this code too, I am trying to remove the interrupt from the code MPU6050_DMP6.ino. Would you kindly tell a look at it and let me know if this is correct. Thank you again.
#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)
Wire.begin();
// 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(9600);
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();
// 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 (fifoCount < packetSize) {
//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,DEC);
Serial.print("\t");
Serial.print(q.x,DEC);
Serial.print("\t");
Serial.print(q.y,DEC);
Serial.print("\t");
Serial.println(q.z,DEC);
#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);
}
}