All the microprocessors use bus type of design to transfer bits within the CPU, memory and input/output devices.
The electrical channels that transfer these bits are known as Buses.
An 8 bit machine has 8 data channels that transfer 8 bits at a time between components of computer.
There are three types of System Buses. These are:
§ Data Bus
§ Address Bus
§ Control Bus
§ We know in a system there are two major tasks.
§ First, processing of data; and second, transfer the data between various devices.
§ The processing of data which is done by CPU is directly related with the clock sped of CPU.
§ The second aspect, which is related to transfer of data between CPU and various other devices, depends upon the width of Data Bus.
§ Width of Data Bus is; numbers of channels can be related to lans of highway.
§ Therefore, more the width of data bus is there more will be data transfer speed, which in turn help to increase the data processing speed.
§ As we know, Data processing two aspects are involved.
· Transfer of Data between various devices.
§ The Computer power is not known for its speed only; it is known for its storage capability that how much a computer is capable of holding data and programs in its memory.
§ The Computer Memory capacity is determined with the width of another type of Bus, known as Address Bus.
§ The Address Bus is used to transfer the addresses of data and instructions between memory and CPU.
§ The Present Day’s Computers have 36 bits of Address Bus.
§ This is an electrical path which is used to transfer the control signals from CPU to other devices.