byte PORTS = 0b10101010;
void setup() {
    DDRC = 0b11111111;
    noInterrupts();
    TCCR1A = 0;
    TCCR1B = 0;
    TCNT1 = 0;
    OCR1A = 200;
    TCCR1B |= (1 << WGM12);
    TCCR1B |= (1 << CS10);
    TIMSK1 |= (1 << OCIE1A);
    interrupts();
}
 
ISR(TIMER1_COMPA_vect) {
    PORTC = PORTS;
    TP = ~PORTS;
}
 
void loop() {}