I2C LCD causes problems

Projects Programming
25

I put the LCD initializing function back in (without the status) and the code now compiles. If you look at the HelloWorld.ino example, it shows how the status variable is used and what it means.

#include <Wire.h>
#include <AccelStepper.h>

#include <hd44780.h>  // main hd44780 header
#include <hd44780ioClass/hd44780_I2Cexp.h>  // i2c expander i/o class header
hd44780_I2Cexp lcd; // declare lcd object: auto locate & auto config expander chip

const int LCD_COLS = 16;
const int LCD_ROWS = 2;

// Define the stepper and the pins it will use
AccelStepper stepper1(AccelStepper::DRIVER, 8, 9); //8=PUL, 9=DIR "AccelStepper::DRIVER" cam be changed to "1" ok

// Define our three input button pins
#define  LEFT_PIN  5
#define  STOP_PIN  4
#define  RIGHT_PIN 3
#define ENA 7  //So the stepper will turn freely when STOP is pressed.

// Define our analog pot input pin
#define  SPEED_PIN A0

// Define our maximum and minimum speed in steps per second (scale pot to these)
#define  MAX_SPEED 5000 //this was set to 500, but I changed to higher number, might set higher later
#define  MIN_SPEED 0.0  //This was set to 0.1, but I changed to 0 so rotation would stop at min setting

float current_speed = 0.0;         // Holds current motor speed in steps/second
int analog_read_counter = 1000;    // Counts down to 0 to fire analog read
char sign = 0;                     // Holds -1, 1 or 0 to turn the motor on/off and control direction
int analog_value = 0;  // Holds raw analog value.
int rpm = 0;
float ips = 0.0;
int timer = 0;

void setup()
{
   // The only AccelStepper value we have to set here is the max speeed, which is higher than we'll ever go
   stepper1.setMaxSpeed(10000.0);

   // initialize serial communications at 9600 bps:
   Serial.begin(9600);

   // initialize and home the LCD display
   lcd.begin(LCD_COLS, LCD_ROWS);

   // Set up the three button inputs, with pullups
   pinMode(LEFT_PIN, INPUT_PULLUP);
   pinMode(STOP_PIN, INPUT_PULLUP);
   pinMode(RIGHT_PIN, INPUT_PULLUP);
   pinMode (ENA, OUTPUT);
}

void loop()
{

   // If a switch is pushed down (low), set the sign value appropriately
   if (digitalRead(LEFT_PIN) == 0)
   {
      sign = 1; digitalWrite(ENA, HIGH);
   }
   else if (digitalRead(RIGHT_PIN) == 0)
   {
      sign = -1; digitalWrite(ENA, HIGH);
   }
   else if (digitalRead(STOP_PIN) == 0)
   {
      sign = 0; digitalWrite(ENA, LOW);
   }
   stepper1.runSpeed();  // This will run the stepper at a constant speed

   // We only want to read the pot every so often (because it takes a long time we don't
   // want to do it every time through the main loop).
   if (analog_read_counter > 0)
   {
      analog_read_counter--;
   }

   else
   {
      analog_read_counter = 3000;  //originally at 3000

      // Now read the pot (from 0 to 1023)
      analog_value = analogRead(SPEED_PIN);

      // Give the stepper a chance to step if it needs to
      stepper1.runSpeed();  //  ********  should not need this.  

      //  And scale the pot's value from min to max speeds
      current_speed = sign * (((analog_value / 1023.0) * (MAX_SPEED - MIN_SPEED)) + MIN_SPEED);


   }

   // Update the stepper to run at this new speed
   stepper1.setSpeed(current_speed);

   rpm = (analog_value / 5.5297);
   ips = (analog_value / 56.8333);

   updateDisplay();
}

void updateDisplay()
{
   static unsigned long timer = 0;
   unsigned long interval = 500;  // update display 2 times / second
   if (millis() - timer >= interval)
   {
      timer = millis();

       lcd.setCursor(2, 0); // set the LCD cursor position
       lcd.print("RPM = ");
       lcd.setCursor(8, 0);
       lcd.print("      "); // overwrite old data
       lcd.setCursor(8, 0); // reset cursor
       lcd.print(rpm);

       lcd.setCursor(2, 1); // set the LCD cursor position
       lcd.print("IPM = ");
       lcd.setCursor(8, 1);
       lcd.print("      "); // overwrite old data
       lcd.setCursor(8, 1); // reset cursor
       lcd.print(ips, 1);
   }
}