Compass to lcd

Projects Programming
1

I have a HMC5883L compass, wired and working on a Uno. (with sketch for HMC5883L loaded) I also have a Sainsmart LCD display wired and working. (with sketch for LCD loaded)

How would I go about getting the LCD to display the values I can see on the serial monitor?

This is what I have so far...

#include <LiquidCrystal.h>
LiquidCrystal lcd(8, 9, 4, 5, 6, 7);

#include <Wire.h>
#include <HMC5883L.h>

HMC5883L compass;

void setup(){
 Serial.begin(9600);
 Wire.begin();
 
 compass = HMC5883L(); //new instance of HMC5883L library
 setupHMC5883L(); //setup the HMC5883L
 
  lcd.begin(16, 2);
  lcd.setCursor(0,0);
  lcd.print("COMPASS ver 1"); 
  lcd.setCursor(0,1);
  lcd.print("Heading=");
}

void loop()
{
  lcd.setCursor(1,10);     // move cursor to second line "1" and 10 spaces over

{
 
 float heading = getHeading();
 Serial.println(heading);
 delay(1000); //only here to slow down the serial print

}

}

void setupHMC5883L(){
 int error; 
 error = compass.SetScale(1.3);
 if(error != 0) Serial.println(compass.GetErrorText(error));

 error = compass.SetMeasurementMode(Measurement_Continuous);
 if(error != 0) Serial.println(compass.GetErrorText(error));
}

float getHeading(){
 MagnetometerScaled scaled = compass.ReadScaledAxis();
 float heading = atan2(scaled.YAxis, scaled.XAxis);

 if(heading < 0) heading += 2*PI;
 if(heading > 2*PI) heading -= 2*PI;

 return heading * RAD_TO_DEG;
}

It displays the COMPASS ver 1 on 1st line and
Heading= on the second line.

Thanks!

2

I am surprised by your question.

The program already outputs to the LCD and you position the cursor ready to output the heading
  lcd.setCursor(1, 10);    // move cursor to second line "1" and 10 spaces overbut you never actually output heading to the LCD.

What is the problem ?

3

It will not display the compass heading on the LCD. Compass is connected to Uno's A4 and A5 pins.

4

lcd.setCursor(1, 10);    // move cursor to second line "1" and 10 spaces overWrong. It is trying to set the cursor to column 1 of line 10.

5

Oh yeah, that would never display on a two line LCD!

Fixed it, but I'm still having trouble finding code that would print the Magnetic heading to the LCD. Did find a sketch another guy is having trouble with... but I can't identify what code is used to display the heading, and his code does not work either, and I did change the LCD pins to my values, not 8,9,4,5,6,7.

#include <Wire.h>
#include <HMC5883L.h>
HMC5883L compass;
int error = 0;
#include <LiquidCrystal.h>
LiquidCrystal lcd(8, 9, 4, 5, 6, 7);

void setup()
{
   
 lcd.begin(16, 2);
 Serial.begin(9600);
Serial.println("Starting the I2C interface.");
Wire.begin();
Serial.println("Constructing new HMC5883L");
compass = HMC5883L();
Serial.println("Setting scale to +/- 1.3 Ga");
error = compass.SetScale(1.3);
if(error != 0)
  Serial.println(compass.GetErrorText(error));
  Serial.println("Setting measurement mode to continous.");
error = compass.SetMeasurementMode(Measurement_Continuous);
if(error != 0)
  Serial.println(compass.GetErrorText(error));

}
void loop()
{
MagnetometerRaw raw = compass.ReadRawAxis();
MagnetometerScaled scaled = compass.ReadScaledAxis();
int MilliGauss_OnThe_XAxis = scaled.XAxis;
float heading = atan2(scaled.YAxis, scaled.XAxis);
float declinationAngle = 0.0457;
heading += declinationAngle;
if(heading < 0)
  heading += 2*PI;
if(heading > 2*PI)
  heading -= 2*PI;
float headingDegrees = heading * 180/M_PI;
Output(headingDegrees);
}
void Output(float headingDegrees)
{
 Serial.print(headingDegrees);
 Serial.println(" Degrees   \t");
 delay(900);
 lcd.write(Serial.read());
}
6 
void Output(float headingDegrees)
{
 Serial.print(headingDegrees);
 Serial.println(" Degrees   \t");
 delay(900);
 lcd.write(Serial.read());
}

Does this successfully print the headingDegrees on the serial monitor?

If so, just change the lcd.write(Serial.read()) to the correct lcd.setCursor and then lcd.print(headingDegrees).