Basics of Computer Hardware

 

Information Representation:

 Internal Electronic circuits(Transistor) works like our electrical circuit in our home as below. 

 

 

 

 

 

In the below transistor illustration, there is no power supply pass through into this transistor, which means it is in OFF state.  if we switch on the power supply then it will be ON state

 

 

 

 

 

 

 

 

Computer needs transistor for below operations

 

 

 

 Human decimal system uses below number system to identify numbers

 

 

  Computer used below BINARY system to recognize numbers

 

 

 

 

 

 

 

The reason why computer scientist groups all the bits as a byte (8 bit) is to avoid false start and finish problem during storage representation of data in memory.  So solution is grouping bits as a byte like below.

  How computer stores Colors, images, Audio and video

 

  Computer stores everything as a numbers inside of its memory

 

 

 

  Computer represents TEXT data in ASCII or UNICODE format which is universal standards

 

 

 

 

 

Computation of Computer

 

  Logic gates are used to perform calculations in computer through CPU...All the logic gates are formed based on the alignments of transistors.

 

 

 

 

 

 

 

 

 

 

 

 

Below is Adder Logic gates to add two bits

 

 

 

 

 

 Carry bit problem

Carry bit problem in BINARY addition

 

 

  

Carry bit problem in DECIMAL addition

 

 

Logic gates handle Carry bit problem as below

 

 

 

Below logic gate circuits joint together to perform large numbers calculation

 

 

 Lot of logic gates circuit are formed to perform below works in computer CPU

 

 

 

 

 Microprocessor executes program from memory with FETCH commands as below

 

 

 

 

 

 

 

 

 

 

 

 

 

Computer Programming

 

Below instructions are human readable program but computer only understands Machine language.

 

 

 

 Programmer only writes program with Mnemonic keyword, but computer decodes these Mnemonic word as Microprocessor execute code to process instructions

 

 Even today computer programs are sequence of bits and bytes and stored in computer memory for execution.  In early days, programmer had to insert these sequence of bits into memory to execute simple program.  As it was very tedious process, computer scientist invented High Level programming language.

 

 

 

 Operation system is set of programs and library which helps user interact with computer through keyboard, mouse and Screen.  This will stand in between hardware and users' programs to facilitate user to execute their instructions without any difficulties.