void setup()
{
    pinMode(8, OUTPUT);
    pinMode(12, OUTPUT);
    pinMode(7, INPUT);
    pinMode(4, INPUT_PULLUP);
    Serial.begin(9600);
}

bool red = LOW;
bool alarm = true; 
bool alarmtrigger = false; 

void loop()
{
    bool motion = digitalRead(7);
    bool button = digitalRead(4);

    if (Serial.available() > 0) {
        char command = Serial.read();
        if (command == 'R' || command == 'r') {
            alarm = !alarm;
            Serial.println(alarm ? "Сигнализация ВКЛ" : "Сигнализация ВЫКЛ");
        }
    }

    if (alarm) {
        if (motion) {
            digitalWrite(8, HIGH);  
            red = HIGH;  

            if (!alarmtrigger) {
                Serial.println("Тревога! Alarm!!!");
                alarmtrigger = true;
            }
        } else {
            digitalWrite(8, LOW);
            alarmtrigger = false;
        }
    } else {
        digitalWrite(8, LOW);
        red = LOW;
    }

    if (!alarm || button) {
        red = LOW;
    }

    digitalWrite(12, red);  
}