Need help programing milis .

Hi guys i am new here and Im planing to build a pinball machine using a arduino as score using a 16x2 display and 3 switches to count points 100,500 and 1000, until here every thing is fine but i wanna know how i can use the milis funcion cause im planing to set a bonus timer if switch 4 was pressed and points should be 5 times comon points during some time like 60 seconds ex: if switch 4 is pressed a = a5 ; b = b5 and soo on during 60 seconds.
Here is my code if someone can help , i will apreciate it.

#include <LiquidCrystal.h> 
LiquidCrystal lcd(12, 11, 5, 4, 3, 2); 

bool button_0State = LOW; // the current STABLE STATE of the input pin 
bool lastButton_0State = LOW; // the previous reading from the input pin 
long lastDebounce_0Time = 0; // the last time the output pin was toggled 

long debounceDelay = 50; // the debounce time; increase if the output flickers 

boolean lastReadButton1; 
boolean lastReadButton2;
boolean lastReadButton3;
boolean lastReadButton4;

unsigned int score = 0; 
int ballnumber = 5; 
int a = 100; 
int b = 500; 
int c = 1000; 


// SETUP=========================================== 
void setup() { 

//input pins for scoring triggers 
pinMode(7, INPUT); 
pinMode(8, INPUT);
pinMode(9, INPUT);
pinMode(10, INPUT); 

// set up the LCD: 
lcd.begin(16, 2); 
lcd.clear(); 
} 

//LOOP============================================== 
void loop() { 
//LCD TOP ROW: SCORE / GAME OVER 
lcd.setCursor(0, 0); 

if (ballnumber < 0) 
{ 
lcd.print("GAME OVER "); 
} 
else 
{ 
lcd.print("SCORE:    BALL:"); 
lcd.print(ballnumber); 
} 
//LCD BOTTOM ROW: NUMERIC SCORE 

lcd.setCursor(0, 1); 
lcd.print(score);

//BONUS w/out milis////////////////////////////////////// 
boolean readButton4 = digitalRead( 10 ) ; 

if (readButton4 == LOW and lastReadButton4 == HIGH) 
{ 
a = a*5; b = b*5; c = c*5; 
} 
lastReadButton4 = readButton4;

//SCORE a 100 PTS ////////////////////////////////////// 
boolean readButton1 = digitalRead ( 8 ) ; 

if (readButton1 == LOW and lastReadButton1 == HIGH) 
{ 
score = score + a; 
} 
lastReadButton1 = readButton1; 

//SCORE a 100 PTS ////////////////////////////////////// 
boolean readButton2 = digitalRead ( 9 ) ; 

if (readButton2 == LOW and lastReadButton2 == HIGH) 
{ 
score = score + b; 
} 
lastReadButton2 = readButton2;

///LOST BALL///BLACK/////////////////////////////////// 
bool reading = digitalRead( 7 ); 

if (reading != lastButton_0State) { 
lastDebounce_0Time = millis(); // reset the time since last stable state 
lastButton_0State = reading; 
} 

if ((millis() - lastDebounce_0Time) > debounceDelay) { 
// test for a transition from low-high or high-low 
if (button_0State != lastButton_0State) { 
button_0State = lastButton_0State; 

if (button_0State == HIGH) { 
ballnumber = ballnumber - 1; 
} 
} 
} 
}

if switch 4 is pressed a = a5 ; b = b5 and soo on during 60 seconds.

Save the value of millis() when switch 4 becomes pressed and set a score multiplier to 5. Then each time through loop() check whether 60 seconds has elapsed (millis() - start time > 60 seconds). If so, then set the score multiplier to one. If not then just carry on.

The demo Several Things at a Time illustrates the use of millis() to manage timing. It may help with understanding the technique.

...R

UKHeliBob:
Save the value of millis() when switch 4 becomes pressed and set a score multiplier to 5. Then each time through loop() check whether 60 seconds has elapsed (millis() - start time > 60 seconds). If so, then set the score multiplier to one. If not then just carry on.

Good morning and thanks for your help.
I tried to do what you succeded but I think I still do not understand how it works in the code, it would be possible for you to fix it for me if you can.
Thank you.

Here is the code i have done till now :

#include <LiquidCrystal.h> 
LiquidCrystal lcd(12, 11, 5, 4, 3, 2); 

bool button_0State = LOW; // the current STABLE STATE of the input pin 
bool lastButton_0State = LOW; // the previous reading from the input pin 
long lastDebounce_0Time = 0; // the last time the output pin was toggled 

long debounceDelay = 50; // the debounce time; increase if the output flickers 
//int bonustime = 0; // tempo para que o bonus funcione

boolean lastReadButton1; 
boolean lastReadButton2;
boolean lastReadButton3;
boolean lastReadButton4;

unsigned long bonusbutton; // tempo desde que o botão foi pressionado
int bonustime = 10000;  // tempo do bonus

unsigned int score = 0; 
int ballnumber = 5; 
int a = 100; 
int b = 500; 
int c = 1000; 

void points();
void bonus();


// SETUP=========================================== 
void setup() { 

//input pins for scoring triggers 
pinMode(7, INPUT); 
pinMode(8, INPUT);
pinMode(9, INPUT);
pinMode(10, INPUT); 

// set up the LCD: 
lcd.begin(16, 2); 
lcd.clear(); 
} 

//LOOP============================================== 
void loop() { 
  points();
  bonus();
}
void points(){
//LCD TOP ROW: SCORE / GAME OVER 
lcd.setCursor(0, 0); 

if (ballnumber < 0) 
{ 
lcd.print("GAME OVER "); 
} 
else 
{ 
lcd.print("SCORE:    BALL:"); 
lcd.print(ballnumber); 
} 
//LCD BOTTOM ROW: NUMERIC SCORE 

lcd.setCursor(0, 1); 
lcd.print(score);


 //SCORE a 100 PTS ////////////////////////////////////// 
boolean readButton1 = digitalRead(8); 

if (readButton1 == LOW and lastReadButton1 == HIGH) 
{ 
score = score + a; 
} 
lastReadButton1 = readButton1; 

//SCORE a 500 PTS ////////////////////////////////////// 
boolean readButton2 = digitalRead(9); 

if (readButton2 == LOW and lastReadButton2 == HIGH) 
{ 
score = score + b; 
} 
lastReadButton2 = readButton2;

///LOST BALL///BLACK/////////////////////////////////// 
bool reading = digitalRead(7); 

if (reading != lastButton_0State) { 
lastDebounce_0Time = millis(); // Redefinir o tempo desde o último estado estável 
lastButton_0State = reading; 
} 

if ((millis() - lastDebounce_0Time) > debounceDelay) { 
// test for a transition from low-high or high-low 
if (button_0State != lastButton_0State) { 
button_0State = lastButton_0State; 

if (button_0State == HIGH) { 
ballnumber = ballnumber - 1; 
} 
} 
} 
}

void bonus(){
  
static unsigned long bonusbutton = digitalRead(10);

if ((millis() - bonusbutton) < bonustime) {

if (digitalRead(10) == HIGH) 
{ 
 a = 500; b = 1000; c = 1500;
}
if ((millis() - bonusbutton) > bonustime) {

if (digitalRead(10) == LOW) 
{ 
a = a; b = b; c = c;
} 
//if ((millis() - bonusbutton) >= bonustime){
//bonustime = millis();
//}
}
}
}

Firstly pull all that code out of loop() into small, well named functions, and leave loop() as a list of function
calls. This will help structure the code and prevent loop() becoming confusing mess of stuff.

Your program is going to be a group of state-machines for each feature of the pinball machine, so try to
keep that reflected in the code - each statemachine should have a function to drive its transitions, called
from loop(), and sub functions for the detail - choose function names well and the code is very readable
and easy to navigate.

MarkT:
Firstly pull all that code out of loop() into small, well named functions, and leave loop() as a list of function
calls. This will help structure the code and prevent loop() becoming confusing mess of stuff.

This is good advice and it is illustrated in Planning and Implementing a Program

...R

PS ,,, please modify your post and use the code button </> so your code looks like this and is easy to copy to a text editor. See How to use the Forum