Hardware components of the PC
Computer Buses
Bus termination

Every bus that carries electrical signals must have termination at the ends. This termination is circuitry that maintains the electrical ones and zeros integrity along the full length of the bus. The buses on the motherboard are terminated by electrical components, or automatically by the last devices on short internal buses. But external buses, an example being the SCSI bus described later in this section, that can extend to six metres or more, need a physical device to provide the termination at both ends. This termination can be provided by termination circuitry on the last device on the end of the bus or an external terminator.