How to use

#include <SPI.h>
#include <Adafruit_GFX.h>
#include <Adafruit_PCD8544.h>
Adafruit_PCD8544 display = Adafruit_PCD8544(7, 6, 5, 4, 3);
#define RED 8
#define GREEN 9
bool redLed =1;
bool greenLed =1;
void setup() {
  display.begin();
  display.setContrast(60);
  display.clearDisplay();
  pinMode(RED,OUTPUT);
  pinMode(GREEN,OUTPUT);
  digitalWrite(RED,1);
  digitalWrite(GREEN,1);
}
void displayAlarm(){
  display.clearDisplay();
  display.drawRect(0,0,84,48,BLACK);
  display.drawRect(1,1,82,46,BLACK);
  display.setTextSize(2);
  display.setTextColor(BLACK);
  display.setCursor(12,16);
  display.println("ALARM");
  display.display();
}
void displayOK(){
  display.clearDisplay();
  display.drawRect(0,0,84,48,BLACK);
  display.drawRect(1,1,82,46,BLACK);  
    display.setTextSize(3);
  display.setTextColor(BLACK);
  display.setCursor(18,12);
  display.println("OK!");
  display.display();
}
void loop() {
  displayAlarm();
  for(int i=0;i<4;i++){
    digitalWrite(RED,!digitalRead(RED));
    delay(1000);
  }
  displayOK();
  digitalWrite(GREEN,0);
  delay(5000);
  display.clearDisplay();
  display.display();
  digitalWrite(GREEN,1);
 
}