Hello, I encountered an error while trying to extract data (roll position) from gyro-accelerometor MPU6050, and display it on OLED SSD1306 (128 x 64pix). From the serial monitor it reads:
Initializing I2C devices...
Testing device connections...
MPU6050 connection successful
Send any character to begin DMP programming and demo:
Initializing DMP...
DMP Initialization failed (code 1)
According to a line in setup, DMP initialisation failed code 1 is due to initial memory load failed. My sketch size is 22,572 bytes (of a 32,256 byte maximum).
My sketch is based on MPU6050_DMP6 obtained from Github. The sketch correctly calculated roll position using MPU6050 data before I added Adafruit libraries and other display purposes codes for SSD1306. The code 1 error only appeared after codes for SSD1306 was added. I have tried in a separate sketch to make sure that the functionalities and codes for SSD1306 are correct.
I hope you can understand the problem and help me to solve it 
The libraries for MPU6050 and SSD1306 can be found at:
My sketch is as follows:
#include <Wire.h>
//include SSD1306 libraries
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include "I2Cdev.h"
#include "MPU6050_6Axis_MotionApps20.h"
#if I2CDEV_IMPLEMENTATION == I2CDEV_ARDUINO_WIRE
#include "Wire.h"
#endif
MPU6050 mpu;
#define LED_PIN 13
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
//SSD1306 pins
#define OLED_DC 11
#define OLED_CS 12
#define OLED_CLK 10
#define OLED_MOSI 9
#define OLED_RESET 13
Adafruit_SSD1306 display(OLED_MOSI, OLED_CLK, OLED_DC, OLED_RESET, OLED_CS);
// ================================================================
// === INTERRUPT DETECTION ROUTINE ===
// ================================================================
volatile bool mpuInterrupt = false; // indicates whether MPU interrupt pin has gone high
void dmpDataReady() {
mpuInterrupt = true;
}
// ================================================================
// === INITIAL SETUP ===
// ================================================================
void setup() {
//Initialise ssd13006 display
display.begin(); // by default, generate the high voltage is generated from the 3.3v line internally
display.clearDisplay(); // clears the screen and buffer
display.display();
// 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
// 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() {
// Serial.print(F("dmpReady =\t"));
// Serial.println(dmpReady);
// if programming failed, don't try to do anything
if (!dmpReady) return;
// Serial.print(F("mpuInterrupt =\t"));
// Serial.println(mpuInterrupt);
// reset interrupt flag and get INT_STATUS byte
mpuInterrupt = false;
mpuIntStatus = mpu.getIntStatus();
// Serial.print(F("mpuIntStatus =\t"));
// Serial.println(mpuIntStatus);
// get current FIFO count
fifoCount = mpu.getFIFOCount();
// Serial.print(F("fifoCount =\t"));
// Serial.println(fifoCount);
// 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;
// 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);
float roll = ypr[2] * 180/M_PI;
ssd1306_display_roll(roll);
Serial.print(F("Roll =\t"));
Serial.println(roll);
// blink LED to indicate activity
blinkState = !blinkState;
digitalWrite(LED_PIN, blinkState);
}
}
void ssd1306_display_roll(float roll){
//display roll value
display.setTextSize(2);
display.setTextColor(WHITE);
display.setCursor(0,21);
display.print("Roll = ");
display.print(roll);
// display.println("°");
display.display();
display.clearDisplay();
}