Arduino Digital Compass Project with SSD1306 OLED Display

In this video lesson we add an SSD1306 OLED to our Arduino Uno R4 WiFi IMU project. The schematic we use for the project is:

OLED IMU — This schematic shows how to connect the SSD1306 OLED to our IMU Project.

The code below is the program we develop in the video. Remember, you have to use your calibration parameters in the program below. I showed you how to calibrate your system in THIS LESSON.

#include <Adafruit_MPU6050.h>
#include <Adafruit_Sensor.h>
#include <Wire.h>
#include <QMC5883LCompass.h>

#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <math.h>

int screenWidth=128;
int screenHeight=64;
int rst = -1;
Adafruit_SSD1306 dsp(screenWidth, screenHeight, &Wire, rst);

float AxRaw,AyRaw,AzRaw,GxRaw,GyRaw,GzRaw,MxRaw,MyRaw,MzRaw;
float AxCal,AyCal,AzCal,GxCal,GyCal,GzCal,MxCal,MyCal,MzCal;
float rollA,pitchA,yawM,rollC,pitchC,yawC;
float rollG = 0;
float pitchG =0 ;
float yawG = 0;
float deltaRoll = 0;
float deltaPitch = 0;
float deltaYaw = 0;
float alpha = .1;

float rollCrad;
float pitchCrad;
float MxCalH;
float MyCalH;

int tStart =millis();
Adafruit_MPU6050 mpu;
QMC5883LCompass compass;

void setup() {
  // put your setup code here, to run once:
Serial.begin(115200);

dsp.begin(SSD1306_SWITCHCAPVCC,0x3C);
dsp.clearDisplay();
dsp.display();

mpu.begin();
mpu.setI2CBypass(true);
compass.init();
mpu.setGyroRange(MPU6050_RANGE_1000_DEG);
delay(100);
}

void calibrateSensors() {
    const float axOffset = 0.45407887789180545;
    const float ayOffset = 0.09432915233553185;
    const float azOffset = -0.4614157209191969;
    const float axScale = 0.10141341897341144;
    const float ayScale = 0.10141341897341144;
    const float azScale = 0.10141341897341144;
    const float gxOffset = -2.277507235645022;
    const float gyOffset = 0.8794902155258137;
    const float gzOffset = -0.5729577951308232;
    const float mxOffset = -103.48885017294003;
    const float myOffset = -96.80085481152321;
    const float mzOffset = 923.8042898128733;
    const float mxScale = 0.001156333898601669;
    const float myScale = 0.001012882116988885;
    const float mzScale = 0.0009400860982065997;


    AxCal = (AxRaw - axOffset) * axScale;
    AyCal = (AyRaw - ayOffset) * ayScale;
    AzCal = (AzRaw - azOffset) * azScale;
    GxCal = GxRaw*180/PI - gxOffset;
    GyCal = GyRaw*180/PI - gyOffset;
    GzCal = GzRaw*180/PI - gzOffset;
    MxCal = (MxRaw - mxOffset) * mxScale;
    MyCal = (MyRaw - myOffset) * myScale;
    MzCal = (MzRaw - mzOffset) * mzScale;
}
void loop() {
  // put your main code here, to run repeatedly:
compass.read();
sensors_event_t a, g, temp;
mpu.getEvent(&a, &g, &temp);

AxRaw = a.acceleration.x;
AyRaw = a.acceleration.y;
AzRaw = a.acceleration.z;

GxRaw = g.gyro.x;
GyRaw = g.gyro.y;
GzRaw = g.gyro.z;

MxRaw= compass.getX();
MyRaw= compass.getY();
MzRaw= compass.getZ();

calibrateSensors();

rollA = atan2(AyCal,sqrt(AzCal*AzCal + AxCal*AxCal))*180/PI;
pitchA = atan2(AxCal,sqrt(AzCal*AzCal + AyCal*AyCal))*180/PI;

deltaRoll = GxCal*(millis()-tStart)/1000.;
deltaPitch = -GyCal*(millis()-tStart)/1000.;
deltaYaw = -GzCal*(millis()-tStart)/1000.;
tStart = millis();

rollG = rollG + deltaRoll;
pitchG = pitchG + deltaPitch;
yawG = yawG + deltaYaw;

rollC = alpha*(rollA) + (1-alpha)*(rollC+deltaRoll);
pitchC = alpha*(pitchA) + (1-alpha)*(pitchC+deltaPitch);

rollCrad=rollC*PI/180;
pitchCrad=pitchC*PI/180;

MxCalH=MxCal*cos(pitchCrad)-MyCal*sin(rollCrad)*sin(pitchCrad)-MzCal*cos(rollCrad)*sin(pitchCrad);
MyCalH=MyCal*cos(rollCrad) - MzCal*sin(rollCrad);

yawM = atan2(MyCalH,MxCalH)*180./PI;
yawM=int(yawM+360)%360;
if (abs(yawM-yawC)>=180){
  yawC=yawM;
}
if (abs(yawM-yawC)<180){
yawC = alpha*(yawM) + (1-alpha)*(yawC + deltaYaw);
}

// Serial.print("yawC:");Serial.print(yawC);Serial.print(',');
// Serial.print("yawM:");Serial.print(yawM);Serial.print(',');
// Serial.print("yawG:");Serial.print(yawG);Serial.print(',');
// Serial.print("LL:");Serial.print(-90);Serial.print(',');
// Serial.print("UL:");Serial.println(90);

Serial.print("rollC:");Serial.print(rollC);Serial.print(',');
Serial.print("pitchC:");Serial.print(pitchC);Serial.print(',');
Serial.print("yawC:");Serial.print(yawC);Serial.print(',');
Serial.print("LL:");Serial.print(-90);Serial.print(',');
Serial.print("UL:");Serial.println(90);

dsp.clearDisplay();
dsp.setTextColor(WHITE);
dsp.setCursor(0,0);
dsp.print("Ultimate Avionics");
dsp.setCursor(0,9);
dsp.print("R: "); dsp.print(int(rollC));
dsp.setCursor(40,9);
dsp.print("P: ");dsp.print(int(pitchC));
dsp.setCursor(80,9);
dsp.print("Y: ");dsp.print(int(yawC));

dsp.display();
delay(100);
}

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#include <Adafruit_MPU6050.h>

#include <Adafruit_Sensor.h>

#include <Wire.h>

#include <QMC5883LCompass.h>

#include <Adafruit_GFX.h>

#include <Adafruit_SSD1306.h>

#include <math.h>

int screenWidth=128;

int screenHeight=64;

int rst = -1;

Adafruit_SSD1306 dsp(screenWidth, screenHeight, &Wire, rst);

float AxRaw,AyRaw,AzRaw,GxRaw,GyRaw,GzRaw,MxRaw,MyRaw,MzRaw;

float AxCal,AyCal,AzCal,GxCal,GyCal,GzCal,MxCal,MyCal,MzCal;

float rollA,pitchA,yawM,rollC,pitchC,yawC;

float rollG = 0;

float pitchG =0 ;

float yawG = 0;

float deltaRoll = 0;

float deltaPitch = 0;

float deltaYaw = 0;

float alpha = .1;

float rollCrad;

float pitchCrad;

float MxCalH;

float MyCalH;

int tStart =millis();

Adafruit_MPU6050 mpu;

QMC5883LCompass compass;

void setup() {

// put your setup code here, to run once:

Serial.begin(115200);

dsp.begin(SSD1306_SWITCHCAPVCC,0x3C);

dsp.clearDisplay();

dsp.display();

mpu.begin();

mpu.setI2CBypass(true);

compass.init();

mpu.setGyroRange(MPU6050_RANGE_1000_DEG);

delay(100);

}

void calibrateSensors() {

const float axOffset = 0.45407887789180545;

const float ayOffset = 0.09432915233553185;

const float azOffset = -0.4614157209191969;

const float axScale = 0.10141341897341144;

const float ayScale = 0.10141341897341144;

const float azScale = 0.10141341897341144;

const float gxOffset = -2.277507235645022;

const float gyOffset = 0.8794902155258137;

const float gzOffset = -0.5729577951308232;

const float mxOffset = -103.48885017294003;

const float myOffset = -96.80085481152321;

const float mzOffset = 923.8042898128733;

const float mxScale = 0.001156333898601669;

const float myScale = 0.001012882116988885;

const float mzScale = 0.0009400860982065997;

AxCal = (AxRaw - axOffset) * axScale;

AyCal = (AyRaw - ayOffset) * ayScale;

AzCal = (AzRaw - azOffset) * azScale;

GxCal = GxRaw*180/PI - gxOffset;

GyCal = GyRaw*180/PI - gyOffset;

GzCal = GzRaw*180/PI - gzOffset;

MxCal = (MxRaw - mxOffset) * mxScale;

MyCal = (MyRaw - myOffset) * myScale;

MzCal = (MzRaw - mzOffset) * mzScale;

}

void loop() {

// put your main code here, to run repeatedly:

compass.read();

sensors_event_t a, g, temp;

mpu.getEvent(&a, &g, &temp);

AxRaw = a.acceleration.x;

AyRaw = a.acceleration.y;

AzRaw = a.acceleration.z;

GxRaw = g.gyro.x;

GyRaw = g.gyro.y;

GzRaw = g.gyro.z;

MxRaw= compass.getX();

MyRaw= compass.getY();

MzRaw= compass.getZ();

calibrateSensors();

rollA = atan2(AyCal,sqrt(AzCal*AzCal + AxCal*AxCal))*180/PI;

pitchA = atan2(AxCal,sqrt(AzCal*AzCal + AyCal*AyCal))*180/PI;

deltaRoll = GxCal*(millis()-tStart)/1000.;

deltaPitch = -GyCal*(millis()-tStart)/1000.;

deltaYaw = -GzCal*(millis()-tStart)/1000.;

tStart = millis();

rollG = rollG + deltaRoll;

pitchG = pitchG + deltaPitch;

yawG = yawG + deltaYaw;

rollC = alpha*(rollA) + (1-alpha)*(rollC+deltaRoll);

pitchC = alpha*(pitchA) + (1-alpha)*(pitchC+deltaPitch);

rollCrad=rollC*PI/180;

pitchCrad=pitchC*PI/180;

MxCalH=MxCal*cos(pitchCrad)-MyCal*sin(rollCrad)*sin(pitchCrad)-MzCal*cos(rollCrad)*sin(pitchCrad);

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Arduino Digital Compass Project with SSD1306 OLED Display

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