WHAT ARE BUS STRUCTURES IN COMPUTER ?

BUS STRUCTURES 

To know what are bus structures you need to go through what is a bus ?
A bus is group of wires that transfers data to different parts of the computer system.
  • The central processing unit, memory unit,  I/O unit are the hardware components of the computer. They work together for communication between the modules.
  • A bus that connects major computer components(CPU, memory, I/O) is called a system bus.
  • The system bus is separated into three functional groups:

  • Data Bus 
  • Address Bus
  • Control Bus

1.   DATA BUS

  • A data bus is a system within a computer or device, consisting of a connector or set of wires, that provides transportation for data. Different kinds of data buses have evolved along with personal computers and other pieces of hardware.
  • This means that CPU can read data on these lines from the memory or from a port, as well as send data out on lines to a memory location or to a port. Therefore, data bus lines are bi-directional.
  • The communication between peripheral and CPU is activated by giving output enable pulse to the peripheral.

2.  ADDRESS BUS

  • It is an unidirectional bus.
  • The address bus consists of 16, 20, 24 or more parallel signal lines.
  • On these lines the CPU sends out the address of the memory location or I/O port that is to be written to or read form.
  • Here, the communication is one way, the address of the memory is send from CPU to memory and I/O port and hence these are unidirectional.
3. CONTROL BUS

  • The control line regulate the activity on the bus.
  • The CPU sends signals on the control bus to enable the outputs of addressed memory devices or port devices.
  • Fig 2 shows bus interconnection scheme.

Fig 2 : Bus interconnection scheme

0 comments