CPU design and architecture

CPU design and architecture

CPU stands for “Central Processing Unit”. High level CPU design is easy to understand if a person knows how to design simple as possible computer/CPU. ‘Simple As Possible computer’ is abbreviated as “SAP”.

In a computer, mobile phones, digital music players, remote control, TV circuits, automatic machines etc, CPU plays central and vital role in their working. CPU is just like the “BRAIN” which is common in every creature BUT rest of the structure is different in them. Following similar concept, we come to know that computer, mobile phones, digital music players, remote control , automatic machines etc, have CPU in common But rest of the structure differs.

CPU is just one part of the whole structure and it is responsible to make ‘CALCULATIONS/DECISION and ORDERS’ only. Any thing that only makes ‘calculations/decision and an order’ is not capable of doing any real thing. Although I have brain but if I was unfortunate and had no hands then how could I write this article? If I was unable to hear then I would be called DEAF although having the same brain as normal human being. Following similar concept, computers and other automatic machines have only structural difference and they have CPU circuit in common. Hence, CPU circuit gets top position in controlled circuits.

One main advantage of controlled circuits that uses CPU circuit is that they are programmable. This implies that one can get multiple functions from same circuit by reprogramming it in desired way. Computer which uses CPU follows our instructions and we can get desired work out of it by installing software which contains our desired instructions.


At the end one important question arises!!!
Although we are convinced that CPU is basic unit of every controlled circuit
BUT

WHAT is its internal circuit and how it WORKS???

CPU internal Circuit and Working

Truly saying CPU is combination of REGISTERS, COUNTERS, FLIP-FLOPS, HALF ADDERS, FULL ADDERS, MULTIPLEXERS, DEMULTIPLEXERS, ENCODERS, DECODERS, AND SOME BASIC GATES.

CPU has FIVE main circuits/units which are made from above mentioned sub circuits. These five main units are listed below.

1. Program Counter
2. Memory
3. Control Unit
4. Arithmetic Logic Unit
5. Accumulator

OK, now wait for further details on these basic units. I will publish them in other posts! Enjoy!