8051 Micro-controller

• CPU (Central Processing Unit)
  • Execute information stored in memory
• I/O (Input/output) devices
  • Provide a means of communicating with CPU
• Memory

 RAM (Random Access Memory)

RAM is a temporary storage of programs that computer is running. The data is lost when computer is off.

 ROM (Read Only Memory)

ROM contains programs and information essential to operation of the computer. The information cannot be changed by use, and is not lost when power is off. It is called non-volatile memory.

Click On Image For Zoom View

Inside CPUs:

The CPU has various component inside itself. these are

1. Registers :

• The CPU uses registers to store information temporarily.
• Registers can be 8-, 16-, 32-, or 64-bit.
• The disadvantage of more and bigger registers is increased the cost of such a CPU.

2. ALU (arithmetic/logic unit) :

ALU performs arithmetic functions such as add,  subtract, multiply, and divide, and  logic functions such as AND, OR, and NOT.

3. Program counter :

Program counter points to the address of the next instruction to be executed.

4. Instruction decoder :

Instruction decoder mainly interprets the instruction fetched into the CPU.