Full transcript of “L-1.2: Von Neumann's Architecture | Stored Memory Concept in Computer Architecture”. Click a timestamp to open the video at that moment. Need another video? Use the YouTube transcript generator.
0:00 Hello friends, welcome to Gate Smashers In today's video, we are going to discuss about Von Newmann's architecture or we call it stored memory architecture or stored memory program What does it mean by stored memory? Where we keep two things inside memory one is data and second is program or set of instructions Data means like we write in program or in processing in C program int A=10, B=20, C=A+B the kind of variables or constants we are defining there where will we store all this data? inside memory! Which memory? Main memory!
0:47 and secondly we store, program Program means set of instructions Instructions are how to do work we have many different type of instruction set available Like if you have heard about MBI, MOV command we have ADD, SUB, branch statement All these commands or processes has different commands All these commands and this data where to store it? In one memory and which memory is that? Main memory Yes, you can store it in different addresses in main memory In some addresses you can store instructions and in some addresses you can store data Its opposite Harvard architecture which was opposite of Von Newmann's It said that we will store instruction set in different memory
1:36 and data in different memory. But here we are keeping both things in same memory And if you look carefully, in today's time whatever architecture we are using We are keeping data and program in main memory Secondly we have here is component This Von Newmann's diagram, Von Newmann's architecture Basically it also tells us which components of basic computer architecture. Which help in processing data What components are there to convert input to output So one is main memory where we are keeping two things data and instructions After that comes our CPU CPU central processing unit And from here main work starts
2:25 In this we have different components First is arithmetic and logical unit, ALU What is the purpose of ALU? In ALU many circuits are available In digital we have different circuits We have adder, we have subtractor With the help of which we do addition, subtraction, multiplication, division, AND operation, OR operation, XOR, AND and we have shift operation Many operations we use like arithmetic operation or logical operation We perform them through ALU And in ALU different circuits are available which help in performing all these operations Then we have registers
3:11 Registers are basically the fastest memory available we have is registers They store temporary data and size is very small Smallest size memory is called registers and it is storing data temporarily How much size can it be basically? Let's say 8 bits, means 1 byte 16 bits So basically we have sequence of bits Sequence of bits is called registers Or you can say sequence of flip flops Because flip flops also store one bit So if you combine multiple flip flops it will become registers But the important point here is that why are registers used?
3:59 When we already have main memory available So what is the benefit of the register when there is memory? And why is the register embedded on the CPU chip? The reason is speed Any operation we perform Let's say A=10, B=20, C=A+B Now where is this data stored? In main memory Where will it perform? This is arithmetic operation Where will it perform? In ALU. So ALU has a very fast speed And the main memory is also fast But compatible to ALU is very slow Now what will happen? If speed mismatches, One person is working fast And other is working slowly Then obviously there will be a burden on one person So the registers help to reduce that burden
4:45 What registers do is Temporarily store the data, the intermediate results, the output and input They are used to store them temporarily and intermediately You must have heard the name of many different registers. Although we will discuss this in detail later But like program counter The next instruction to execute, that address is stored in program counter This is also a register Apart from that we have accumulator Which is used to store the intermediate results There is input register, output register, MAR, memory addressable So all these registers help to speed up the processing And work as an intermediator between ALU and main memory
5:31 Then we have control unit Control unit is a very important factor We have two things in control unit One is timing signal And the second is control signals. Timing signal basically means timing Means which instruction will be executed first and which will be after Means let's say we have 10 instructions in the program Now which instructions to execute first and which later This is basically a very important factor Let's say if you drive a car Now we know in the car what the instructions are
6:17 First we press the clutch Then we put the gear Then we accelerate slowly this sequence of instructions Sequence of steps Do not do them up and down If you do so,then the output can be different So to do this work we need dedicated hardware And that hardware is basically control unit So timing signals generate timing here Every timing signal performs some action Then we have control signal Control signal basically, That we have so many registers, input register, output register, PC, accumulator There are many registers We can read them, we are writing something in them How to control all these, It should not be that you are accessing the data
7:07 And the registers are busy somewhere else, executing some other work To perform all these read write operations We use control signals in the register Control signals are like your mind Like our arms, our legs How to move them, how to give instructions Who is giving these instructions, our mind is So here the control signals Control signals control them How to read and access the registers Who has to do it first, who has to do it later So this control unit is very important here Which is playing a major role. This Von Neumann's architecture, is a very basic architecture given in 1945 But the main point here is How the data is processed
7:54 The data that we keep in the main memory We call the data from there to the CPU And we process the registers in the CPU, the ALU processes them And gives the output back to the main memory And from the main memory to the next Where ever it is, the user has to show on the monitor Or have to store in the secondary memory This is how we process the data So this also helps you As a computer science student, you will know How the work is done in a computer So it is showing that too here So these are all the main components After that we have input-output system Means we have peripheral devices Input devices like keyboard, monitors And output devices, we have monitors So all these devices come to our next level So basically we have this main architecture It tells us what is the benefit of these components
8:43 Now how can we attach these components Attaching means network topology Like we study in networks There is mesh topology, bus topology, star topology it helps different components Because we have main memory, registers Control unit, means this is the whole CPU How we have to connect them We connect them through bus There are different types of buses Means we have address bus, data bus There are different types of buses And how their work is We will discuss this later in the next video We basically implement this with the help of multiplexers So this is the Von Neumann's diagram Von Neumann's architecture Basically you have to remember this That stored memory program is there What is there in memory and apart from this we have all the components
9:31 And what is the benefit of those components, how they perform So this is all about the Von Neumann's architecture Thank you.
