15.2. Unit 6: Execution of Program and Programming Languages

So, the Unit Objective of this particular unit is. Objective 1 we have to define it like that illustrate the execution of a program in a processor. So this is in Analysis level. That means, once you get a program then you will able to analyse exactly what task is performed by this particular program and how it is going to execute in a computer. Objective 2 describe the format of Instruction. So, program is nothing but a set of instruction which will be executed in sequence. So, we are going to see; what is the format of instruction that we are having in the Instruction set of the processor. It is slightly in the design level in the higher level. Once you know the principal then you will be able to design an Instruction set for a processor. Objective 3 explain different level of programming languages. So in a knowledge level just we are going to give information what are the different kinds of programming language we have in for computer programming. So, it is in the knowledge level just we will give the brief idea about it.

The objectives of this unit are aimed at achieving fundamental understanding about the execution of programs in a computer system. The first objective focuses on the illustration of program execution within a processor. This involves understanding how a given program is executed and what task it accomplishes, which falls into the analysis level of learning. The second objective deals with the format of instructions, highlighting that instructions are the building blocks of programs that execute sequentially. Learning this enhances the ability to design instruction sets, which relates to design-level learning. The third objective introduces different types of programming languages, imparting knowledge about their classifications, helping students understand the spectrum of programming paradigms.

Consider cooking in a kitchen. Just like a recipe outlines the steps to create a dish, a program in a computer is a set of instructions the computer must follow. Understanding how to execute that recipe (program) and knowing how to modify it for different dishes (instructions) helps you become a better cook (programmer). Each type of dish represents different programming languages, each with its own style and flavor.

Now, in this particular module we have discuss about the working principle of Computers and the basic Components of the Computer. In the top level view of Computer Components are coming like that the main Component of a Computer is the processor, which is your Central Processor Unit. So, this CPU is going to perform our task depending on the program that we are going to execute. But, the processor cannot work alone. So, we have to connect the Main Memory which is the storage device because processor works on von Neumann stored program principle. So we have to store our program and data in the Memory. So this is the Main Memory component. Here we are having the program just we are writing as Instruction and in some Memory location we have our data. So, processor works with the contents of the Main Memory, but how to take the information to the Main Memory and how we are going to get the result to the users. For that we need some I/O devices Input Output devices.

This chunk explains the essential components required for a computer to execute a program. The Central Processing Unit (CPU) is identified as the main component, responsible for executing tasks according to the provided program. However, the CPU relies on other components like Main Memory, where the data and instruction set reside, following the von Neumann architecture which emphasizes a stored-program concept. The necessity of Input/Output devices is also highlighted, as they facilitate data transfer between the computer's memory and the user. This holistic view is vital for understanding how a computer system operates seamlessly from receiving input to executing a program and outputting results.

Think of a CPU as a chef in a restaurant. The Main Memory is like the pantry where ingredients (data) are stored, and the Input/Output devices are like the waiters who take orders (input) from customers and deliver the finished dishes (output) back to them. Just as a chef cannot work without access to ingredients or the assistance of waiters, a CPU cannot operate effectively without memory and I/O devices.

So, we know that while going to execute an Instruction that Instruction Cycle is having basically 2 phase mainly 2 phase. One is your Fetch, second one is Execute and we have seen in the Fetch Cycle what we are going to do we are going to Fetch the Instruction from the Memory and going to bring it to the processor and once we get the Instruction our job is to execute that particular Instruction. So, we are going to execute that particular Instruction inside the processor.

This section introduces the fundamental operation of executing instructions in a computer system termed as the Instruction Cycle. The cycle consists of two critical phases: Fetch and Execute. In the Fetch phase, the CPU retrieves an instruction from the main memory, bringing it to the processor for processing. Once fetched, in the Execute phase, the CPU performs the action specified by the instruction. This structured approach allows the CPU to manage and process numerous instructions sequentially, ensuring a logical workflow. Understanding this cycle is foundational for grasping how computers function at the operational level.

Imagine making a telephone call where fetching a phone number is like the Fetch phase (you look it up), and actually dialing and talking to the person is like the Execute phase (you perform the action). Just as you need both steps to successfully communicate, the CPU requires both the Fetch and Execute steps to run programs.

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