Arduino script throws error "X was not declared in this scope" - arduino

Question

Code and scheme from this link: https://www.makerspaces.com/15-simple-arduino-uno-breadboard-projects/
I'm a total beginner. I just started and I had some difficulties with the board, my PC isn't recognising the board and I wanted to create a simple circuit to test some commands, to see if I solved the problem
Full code:
// Pin assignement
#define btnPin 7
#define led1Pin 8
#define led2Pin 9
#define led3Pin 10
enum fcnMode {
OFF,
LED1,
LED2,
LED3,
FADE1,
ALL,
BLINK,
NBSTATE
}; // OFF = 0 and NBSTATE=7
int ledState1 = LOW,ledState2 = LOW,ledState3 = LOW; // ledState used to set the LED
unsigned long buttonState = 0;
int funcState=0;
unsigned long currentMillis1,currentMillis2,currentMillis3; // will store current time
unsigned long previousMillis1,previousMillis2,previousMillis3; // will store last time LED was updated
const long interval1 = 100; // interval at which to blink (milliseconds)
const long interval2 = 300;
const long interval3 = 500;
/******************************************************************\
* PRIVATE FUNCTION: setup
*
* PARAMETERS:
* ~ void
*
* RETURN:
* ~ void
*
* DESCRIPTIONS:
* Initiate inputs/outputs
*
\******************************************************************/
void setup(){
Serial.begin(9600); // initialize serial port
pinMode(btnPin,INPUT_PULLUP);
pinMode(led1Pin,OUTPUT);
pinMode(led2Pin,OUTPUT);
pinMode(led3Pin,OUTPUT);
}
/******************************************************************\
* PRIVATE FUNCTION: loop
*
* PARAMETERS:
* ~ void
*
* RETURN:
* ~ void
*
* DESCRIPTIONS:
* Main Function of the code
\******************************************************************/
void loop(){
buttonPressed();
setMode();
}
/******************************************************************
* SUBFUNCTIONS
\******************************************************************/
void buttonPressed() {
buttonState = pulseIn(btnPin,HIGH,1000000);
if (buttonState > 50){
funcState += 1;
Serial.print("Button state n: ");
Serial.println(funcState);
}
funcState=funcState%NBSTATE;
}
void setMode() {
// All Off
digitalWrite(led1Pin,LOW);
digitalWrite(led2Pin,LOW);
digitalWrite(led3Pin,LOW);
Serial.print("Function : ");
Serial.println(funcState);
switch(funcState){
case OFF:
break;
case LED1:
digitalWrite(led1Pin,HIGH);
break;
case LED2:
digitalWrite(led2Pin,HIGH);
break;
case LED3:
digitalWrite(led3Pin,HIGH);
break;
case FADE1:
fade1();
break;
case ALL:
digitalWrite(led1Pin,HIGH);
digitalWrite(led2Pin,HIGH);
digitalWrite(led3Pin,HIGH);
break;
case BLINK:
blinkLed1();
blinkLed2();
blinkLed3();
break;
}
}
void fade1(){
int brightness = 0;
int fadeAmount = 5;
for (brightness=0;brightness<=255;brightness+=fadeAmount){
analogWrite(led1Pin, brightness);
delay(30);
}
for (brightness=255;brightness>=0;brightness-=fadeAmount){
analogWrite(led1Pin, brightness);
delay(30);
}
}
void blinkLed1(){
currentMillis1 = millis();
if (currentMillis1 - previousMillis1 >= interval1) {
// save the last time you blinked the LED
previousMillis1 = currentMillis1;
// if the LED is off turn it on and vice-versa:
if (ledState1 == LOW) {
ledState1 = HIGH;
} else {
ledState1 = LOW;
}
// set the LED with the ledState of the variable:
digitalWrite(led1Pin, ledState1);
}
}
void blinkLed2(){
currentMillis2 = millis();
if (currentMillis2 - previousMillis2 >= interval2) {
// save the last time you blinked the LED
previousMillis2 = currentMillis2;
// if the LED is off turn it on and vice-versa:
if (ledState2 == LOW) {
ledState2 = HIGH;
} else {
ledState2 = LOW;
}
// set the LED with the ledState of the variable:
digitalWrite(led2Pin, ledState2);
}
}
void blinkLed3(){
currentMillis3 = millis();
if (currentMillis3 - previousMillis3 >= interval3) {
// save the last time you blinked the LED
previousMillis3 = currentMillis3;
// if the LED is off turn it on and vice-versa:
if (ledState3 == LOW) {
ledState3 = HIGH;
} else {
ledState3 = LOW;
}
// set the LED with the ledState of the variable:
digitalWrite(led3Pin, ledState3);
}
}
Error:
sketch_may09b.cpp: In function 'void setup()':
sketch_may09b:38: error: 'INPUT_PULLUP' was not declared in this scope

Answer 1

Your file extension is .cpp. I think it should be .ino if you are in Arduino IDE. If it doesn't help try just INPUT and add a pullup resistor to your button.