Define a bus. Describe the function of the address bus, control bus and data bus

Bus: 

A bus is a communication path way connecting two or more devices. A key characteristics of a bus is that it is a shared transmission medium. Thus a bus is a wire through which electrical signals can be transmitted. 

There are three types of buses called:

Address bus

Data bus

Control bus

Address Bus: 

The address bus is used by micro processor to transmit the address of the memory location which it wants to access for reading or writing purposes. An address bus is undirectional i.e.electric signals are transmitted in one direction only from micro processor to other devices by this bus. 

Data Bus: 

The data bus is used to transmit data from the memory to micro processor and vice versa. It may be used to transmit data to other devices such as output units. The data bus is bi-directional because data has to pass from microprocessor to memory as well as from memory to the micro processor.

Control Bus: 

The control bus supervises the reading or writing of data. It transmits signals to all the devices at the proper time. In fact, it informs the micro processor that p particular unit has completed its job. 

                  The picture above shows the bus system of a micro computer.