Hello All,
I am chasing my tail with the digitalRead vs the IF/Else control statements. I am using a Sunfounder Mega 2560 with a Sainsmart LCD2004A. You will notice the error message I pasted at the bottom.
I place the Swtichpin definition in various places and I get the same type of errors. I feel like I am looking right at something simple. There is extraneous code from a Ping program I sourced the LCD code from but I don’t call it so it just remains extraneous.
#include <LiquidCrystal_I2C.h>
#include<LCD.h>
#include<Wire.h>
#include <NewPing.h>
#define I2C_ADDR 0x27
#define Rs_pin 0
#define Rw_pin 1
#define En_pin 2
#define BACKLIGHT_PIN 3
#define D4_pin 4
#define D5_pin 5
#define D6_pin 6
#define D7_pin 7
#define ECHO_pin 11
#define TRIGGER_PIN 12
#define MAX_DISTANCE 500
NewPing sonar(TRIGGER_PIN,ECHO_pin, MAX_DISTANCE);
LiquidCrystal_I2C lcd(I2C_ADDR,En_pin,Rw_pin,Rs_pin,D4_pin,D5_pin,D6_pin,D7_pin);
void setup() {
int SwitchPin = 22;
pinMode(SwitchPin,INPUT);
lcd.begin (20,4);
lcd.setBacklightPin(BACKLIGHT_PIN,POSITIVE);
lcd.setBacklight(HIGH);
}
void loop() {
if (digitalRead(SwitchPin) == HIGH)
{ lcd.setBacklight(HIGH);
lcd.home();
lcd.print("Hello Family");
lcd.setCursor (0, 1);
lcd.print("The switch is 33");
}
else
{ lcd.setBacklight(HIGH);
lcd.home();
lcd.print("Hello Family");
lcd.setCursor (0, 1);
lcd.print("The switch is off");}
// put your main code here, to run repeatedly:
}
*ERROR MESSAGE
Arduino: 1.6.6 (Windows 7), Board: “Arduino/Genuino Mega or Mega 2560, ATmega2560 (Mega 2560)”
C:\Users\Robot\Documents\Arduino\I2C_ld_1may16\I2C_ld_1may16.ino: In function ‘void loop()’:
I2C_ld_1may16:32: error: ‘SwitchPin’ was not declared in this scope
if (digitalRead(SwitchPin) == HIGH)
^
exit status 1
‘SwitchPin’ was not declared in this scope
This report would have more information with
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