Why 'LCD' was not declared in this scope

Using Arduino Programming Questions
1 
// AC Current Sensor with LCD By Solarduino
 
// 0- General
 
int decimalPrecision = 2;
 
// 1- AC Current Measurement
 
int CurrentAnalogInputPin = A1;
float mVperAmpValue = 185;
 
float offsetSampleRead = 0;
float currentSampleRead = 0;
float currentLastSample = 0;
float currentSampleSum = 0;
float currentSampleCount = 0;
float currentMean ;
float RMSCurrentMean ;
float adjustRMSCurrentMean ;
float FinalRMSCurrent ;
 
//1.1 Offset AC Current
 
int OffsetRead = 0;
float currentOffset1 = 0;
float currentOffset2 = 0;
float offsetSampleSum =0;
float offsetCurrentMean = 0;
float offsetLastSample = 0;
float offsetSampleCount = 0;
 
//2 - LCD Display
 
#include <LiquidCrystal.h> LCD(8,9,4,5,6,7);
unsigned long startMillisLCD;
unsigned long currentMillisLCD;
const unsigned long periodLCD = 1000;
 
void setup()
 
{
 
// 0- General
 
Serial.begin(9600);
 
// 2 - LCD Display
 
LCD.begin(16,2);
LCD.setCursor(0,0);
startMillisLCD = millis();
 
}
 
void loop()
{
 
// 0- General
 
// 0.1- Button Function
 
int buttonRead;
buttonRead = analogRead (0);
 
//Right button is pressed
if (buttonRead &lt; 60)
{ LCD.setCursor(0,0); LCD.print ("PRESS<select>"); }</select>
 
// Up button is pressed
else if (buttonRead &lt; 200)
{ LCD.setCursor(0,0); LCD.print ("PRESS<select>"); }</select>
 
// Down button is pressed
else if (buttonRead &lt; 400)
{ LCD.setCursor(0,0); LCD.print ("PRESS<select>"); }</select>
 
// Left button is pressed
else if (buttonRead &lt; 600)
{ LCD.setCursor(0,0); LCD.print ("PRESS<select>"); }</select>
 
// Select button is pressed
else if (buttonRead &lt; 800) { OffsetRead = 1; LCD.setCursor(0,0); LCD.print ("INITIALIZING..... "); LCD.setCursor(0,1); LCD.print ("WAIT 5 SEC ..... "); } // 1- AC Current Measurement if(millis() &gt;= currentLastSample + 1)
{
offsetSampleRead = analogRead(CurrentAnalogInputPin)-512;
offsetSampleSum = offsetSampleSum + offsetSampleRead;
 
currentSampleRead = analogRead(CurrentAnalogInputPin)-512 + currentOffset1;
currentSampleSum = currentSampleSum + sq(currentSampleRead) ;
 
currentSampleCount = currentSampleCount + 1;
currentLastSample = millis();
}
 
if(currentSampleCount == 1000)
{
offsetCurrentMean = offsetSampleSum /currentSampleCount;
 
currentMean = currentSampleSum/currentSampleCount;
RMSCurrentMean = sqrt(currentMean);
adjustRMSCurrentMean = RMSCurrentMean + currentOffset2;
FinalRMSCurrent = (((adjustRMSCurrentMean /1024) *5000) /mVperAmpValue);
Serial.print(" The Current RMS value is: ");
Serial.print(FinalRMSCurrent,decimalPrecision);
Serial.println(" A ");
offsetSampleSum = 0;
currentSampleSum =0;
currentSampleCount=0;
}
 
//1.1 - Offset AC Current
 
if(OffsetRead == 1)
{
currentOffset1 = 0;
if(millis()&gt;= offsetLastSample + 1)
{
offsetSampleCount = offsetSampleCount + 1;
offsetLastSample = millis();
}
if(offsetSampleCount == 1500)
{
currentOffset1 = - offsetCurrentMean;
OffsetRead = 2;
offsetSampleCount = 0;
}
}
 
if(OffsetRead == 2)
{
currentOffset2 = 0;
if(millis()&gt;= offsetLastSample + 1)
{
offsetSampleCount = offsetSampleCount + 1;
offsetLastSample = millis();
}
 
if(offsetSampleCount == 2500)
{
currentOffset2 = - RMSCurrentMean;
OffsetRead = 0;
offsetSampleCount = 0;
}
}
 
// 2 - LCD Display
 
currentMillisLCD = millis();
if (currentMillisLCD - startMillisLCD &gt;= periodLCD)
{
LCD.setCursor(0,0);
LCD.print("I=");
LCD.print(FinalRMSCurrent,decimalPrecision);
LCD.print("A                   ");
LCD.setCursor(0,1);
LCD.print("                      ");
startMillisLCD = currentMillisLCD ;
}
 
}
``` whys it that im getting that error
2

i dont know why im getting 'LCD' was not declared in this scope
error

3

Hello Swagometer, Good day.
check the example:
https://www.arduino.cc/reference/en/libraries/liquidcrystal/liquidcrystal/

Example

#include <LiquidCrystal.h>

LiquidCrystal lcd(12, 11, 10, 5, 4, 3, 2);

void setup()
{
  lcd.begin(16,1);
  lcd.print("hello, world!");
}

void loop() {}

Best regards
Markus

4

What do you think this line does?

5

@swagometer, welcome and thanks for using code tags in your first post.

Your topic has been moved to a more suitable location on the forum. Installation and Troubleshooting is not for problems with (nor for advise on) your project.

6

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