Functions? Creating a Radio Hub

Projects Programming
13

I'm confused by the whole millis thing. I understand why it's better than delay in this instance, but I don't know how to implement it.

I tried doing this, but It would switch over to the next screen and back to the 1st before I could react, so something is definitely wrong with the millis function.

#include <Keypad.h>
#include <LiquidCrystal.h>
#include <nRF24L01.h>
#include <RF24.h>
#include <RF24_config.h>
#include <SPI.h>

//Timer
unsigned long startMillis;
unsigned long currentMillis;
const unsigned long ScreenRefresh = 5000;


boolean ScreenTwo = LOW;
boolean doorState = LOW;

//Radio
int msg[1];
RF24 radio(2, 4);
const uint64_t pipes[2] = {
  0xF0F0F0F000LL, 0xF0F0F0F0FFLL
};

//LCD
LiquidCrystal lcd(A0, A1, A2, A3, A4, A5);

//Keypad
const byte ROWS = 4;
const byte COLS = 3;

char hexaKeys[ROWS][COLS] = {
  {'1', '2', '3'},
  {'4', '5', '6'},
  {'7', '8', '9'},
  {'*', '0', '#'}
};
byte rowPins[ROWS] = {3, 5, 6, 7};
byte colPins[COLS] = {8, 9, 10};

Keypad customKeypad = Keypad( makeKeymap(hexaKeys), rowPins, colPins, ROWS, COLS);

void setup() {
  radio.begin();
  radio.setDataRate(RF24_250KBPS);
  radio.setChannel(100);
  radio.setRetries(15, 15);
  radio.openWritingPipe(pipes[0]);
  radio.openReadingPipe(1, pipes[1]);
  radio.setPALevel(RF24_PA_MAX);
  radio.startListening();

  //Timer
  startMillis = millis();

  //Screen 1
  lcd.begin(16, 2);
  MainMenu();

  Serial.begin(9600);
}

void loop() {
  //Timing
  currentMillis = millis();

  //Keypad
  char customKey = customKeypad.getKey();
  if (customKey) {
    Serial.println(customKey);
  }

  //Radio Code
  if (radio.available()) {
    bool done = false;
    while (!done) {
      done = radio.read(msg, 1);

      if (msg[0] == 111) {
        delay(10);
        doorState = HIGH;
      }

      else if (msg[0] == 112) {
        doorState = HIGH;
      }
    }
  }

  // Screen 2
  if (customKey == '*' ) {
    currentMillis = millis();
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("The Coop Door Is");
    ScreenTwo = HIGH;
    
    if (startMillis - currentMillis >= ScreenRefresh) {
      ScreenTwo = LOW;
      lcd.clear();
      MainMenu();
    }
  }

  if (ScreenTwo == HIGH) {
    CoopDoor();
  }
}

void CoopDoor() {
  if (doorState == HIGH) {
    lcd.setCursor(0, 1);
    lcd.print("Open");

  }
  else if (doorState == LOW) {
    lcd.setCursor(0, 1);
    lcd.print("Closed");

  }
}

void MainMenu () {
  lcd.setCursor(0, 0);
  lcd.print("* for Coop");
  lcd.setCursor(0, 1);
  lcd.print("# for Security");
}

Just FYI I also decide to make screen 1 a function called MainMenu, so I could go back to the start without having to press reset.