if (timer == 1)
        ICR1 = icr;
    else if (timer == 3)
        ICR3 = icr;
    else if (timer == 4)
        ICR4 = icr;
    else if (timer == 5)
        ICR5 = icr;

timers {
{ ICR1, TCCR1A, OCR1A, OCR1B },
{ ICR2, TCCR2A, OCR2A, OCR2B }

timers[1][0]

*timers[1][0] = 100;