How to resolve this problem named " 'button' was not declared in this scope " in arduino?

Question

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void setup() {
/*
RGB LED 입출력설정
*/
  pinMode(R_LED_PIN, OUTPUT);
  pinMode(G_LED_PIN, OUTPUT);
  pinMode(B_LED_PIN, OUTPUT); 

  lcd.init();                                                             // LCD 초기화
  lcd.backlight();                                                        // LCD 백라이트 켜기(화면 밝아짐)
  lcd.setCursor(2,0);                                                     // 커서 (2,0)
  lcd.print("*INTERRUPT*");                                               // 글자출력
  delay(500);

  attachInterrupt(digitalPinToInterrupt(BUTTONPIN), button, FALLING);
 /* 인터럽트 설정(아두이노 3번 핀, button 함수 호출, 모드 FALLING */
}

void loop() {
/* 
led_color 함수에 Red, Green에 무작위 값과 Blue에는 0을 인자로 전달

delay를 0~99 사이의 무작위 값으로 설정
*/
  led_color(random(256), random(256), 0);
  int Blue = 0;

  delay(random(100));
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I can't resolve the problem like a title in the interrupt zone: attachInterrupt(digitalPinToInterrupt(BUTTONPIN), button, FALLING);

Arduino uno error makes me crazy!!!!!! Please help me...

Answer 1

You have not shared the whole code but for your understanding I have written code in place of button you have to provide a function checkSwitch.

const byte ledPin = 13;
const byte buttonPin = 2;
 
// Boolean to represent toggle state
 
volatile bool toggleState = false;
 
void checkSwitch() {
  // Check status of switch
  // Toggle LED if button pressed
 
  if (digitalRead(buttonPin) == LOW) {
    // Switch was pressed
    // Change state of toggle
    toggleState = !toggleState;
    // Indicate state on LED
    digitalWrite(ledPin, toggleState);
  }
}
 
void setup() {
  // Set LED pin as output
  pinMode(ledPin, OUTPUT);
  // Set switch pin as INPUT with pullup
  pinMode(buttonPin, INPUT_PULLUP);
 
  // Attach Interrupt to Interrupt Service Routine
  attachInterrupt(digitalPinToInterrupt(buttonPin),checkSwitch, FALLING); 
}
 
void loop() {
  
  // 5-second time delay
  Serial.println("Delay Started");
  delay(5000);
  Serial.println("Delay Finished");
  Serial.println("..............");
}