outb( base + ISR, 0xFF );
outb( base + RCR, 0x20 ); // Reciever to Monitor
outb( base + TCR, 0x02 ); // Transmitter OFF (TCR.LB = 1, Internal Loopback)
outb( base + ISR, 0xFF );
outb( base + RCR, 0x20 ); // Reciever to Monitor
outb( base + TCR, 0x02 ); // Transmitter OFF (TCR.LB = 1, Internal Loopback)