RISC vs. CISC: Understanding the Differences and Pros/Cons of Each Architecture

hello everyone and welcome to amazingphysics today we have an exciting topic to discuss the classification of microprocessors based on their instruction set architectures specifically we will be exploring the fascinating Realms of reduced instruction set Computing and complex instructions at Computing so if you're ready to unravel the secrets Behind These two powerful architecture let's get started [Music] thank you foreign set architecture or is plays a vital role in determining the capabilities and compatibility of a microprocessor the esa determines the types of instructions that a processor can understand and execute as well as the way that those instructions are encoded but before we dive into the classification let's first Define what an instruction set is in simple terms an instruction set is a collection of commands or instructions that a microprocessor can understand and execute these instructions dictate how the processor interacts with memory performs arithmetic and logical operations and controls input output devices different instruction sets can greatly impact a processor's functionality performance and even software compatibility now let's move on to the classification of microprocessors based on their instruction set architectures first let's talk about Sisk which stands for complex instruction set computer cisc processors have a large number of instructions and each instruction can perform complex operations this may make Sisk processors versatile as they can handle a wide range of tasks with fewer instructions however the complexity of these instructions can result in slower execution times and increased design complexity next we have risk which stands for reduced instruction set computer risk processors take a different approach they have a smaller number of simpler instructions each designed to perform a specific operation this Simplicity allows risk processors to execute instructions faster and makes them easier to design however the reduced number of instructions means that risk processors may not be as versatile as their CIS counterparts lastly we have epic which stands for explicitly parallel instruction Computing epic processors combine the features of both sysk and risk architectures they have a large number of instructions like Sisk processors but they also incorporate features that enable them to execute multiple instructions in parallel similar to risk processors this parallel execution capability enhances performance although not to the same sent as pure risk processors to summarize Sisk processors offer versatility with their large number of complex instructions risk processors provide speed and simplicity with their smaller number of simpler instructions and epic processors strike a balance by incorporating parallel execution capabilities along with a larger instruction set apart from these three main classifications there are other notable categories of microprocessors based on their instruction set architectures let's take a quick look at a few of them one such classification is vliw which stands for very long instruction word the liw processors have a very large number of instructions that are packed into a single word this allows the processor to execute multiple instructions in parallel which can significantly improve performance another classification is a sick which stands for application-specific integrated circuit a Sig processors are designed for a specific application they have a custom instruction set that is optimized for the specific needs of the application offering high performance and efficiency lastly we have fpga which stands for field programmable gate array fpga processors are also custom designed but they can be reprogrammed to run different applications this makes them a good choice for applications that need to be updated frequently such as networking devices and medical equip so as you can see there are various classifications of microprocessors based on their instruction set architectures from cisc and risk to Epic voiw a sick and fpga each architecture offers unique advantages and is suitable for specific applications among these architectures risk and Sisk are quite popular let's focus on those and understand more about them now let's turn our attention to Sisk or complex instruction set computer prior to the emergence of risk processors these processors made their Mark in the 1970s at the time computer memory was small and very expensive as a result cisc processors emerged as a solution to address these memory constraints the primary aim of cisc processors was to simplify the coding process and reduce the memory requirements associated with it Sisk processors achieved this goal by incorporating multiple low-level operations within a single instruction this approach enabled the execution of complex tasks with concise and efficient code let's now explore how syst processors architecture were designed to overcome the limitations imposed by the scarcity and cost of computer memory during that era as we mentioned earlier the main objective of assist processor which is to minimize program size by reducing the number of instructions in a program we learned that this is achieved by embedding low-level instructions into a single complex instruction which is later decoded to generate several micro instructions for execution so if a program or software is simplified the hardware needs to step up and be capable of Performing complex tasks this is why a Sisk processor is equipped with complex Hardware components to better understand the architecture let's take a look at the block diagram of a typical Sisk processor one of the key components of assist processor is the the microprogram control unit this unit is responsible for decoding the instructions that are executed by the processor it does this by using a series of micro instructions that are stored in the microcode memory the instruction and data path is another important component of a Sisk processor this path is responsible for fetching the instructions and data that are needed by the processor the instructions are fetched from the memory while the data is fetched from either the memory or the registers the cache and Main memory are also important components of assist processor the cache is a high speed memory that stores frequently accessed instructions and data this helps to improve the performance of the processor by reducing the amount of time that it takes to fetch instructions and data from the main memory the interaction between these components is essential for the efficient operation of assist processor by understanding how these components work together you can gain a better understanding of houses processors work now let's explore a few notable examples of Sisk processors first on our list is the Intel x86 processor the Intel x86 architecture is one of the most widely used Sisk processors in the world you can find it in a diverse range of devices including personal computers laptops servers and even some smartphones its popularity and compatibility have made it a dominant force in the Computing industry another well-known Sisk processor is the Motorola 68000 it gained popularity in the 1980s and 1990s and was widely used in personal computers workstations and even game consoles the Motorola 68 thousands robust performance and flexibility made it a preferred choice for various applications moving on we come to the IBM system 360. this series of mainframe computers introduced in the 1960s marked a significant milestone in the history of computing the system 360 was the first line of computers to adopt the Sisk architecture it quickly gained popularity and became widely used in the business World lastly let's talk about the vax processor the vax or virtual address extension was a series of mini computers introduced in the 1970s it also utilized a Sisk architecture and found popularity in the scientific and Engineering communities the vax series offered powerful processing capabilities making it a preferred choice for computationally intensive tasks these examples demonstrate the wide range of applications and domains where cisc processors have made their mark from personal computers to mainframes Sisk architectures have played a crucial role in powering diverse Computing systems however this complexity also brings both advantages and disadvantages let's explore them further first let's discuss the advantages of Sisk processors Advantage 1 efficiency and complex tasks Sisk processors excel at performing complex tasks efficiently with their extensive instruction set Sisk processors can execute complex operations with a single instruction for example adding two numbers and storing the result in a register can be accomplished with a single instruction simplifying the task and boosting performance Advantage 2 implementation of diverse feature Sisk processors offer the ability to implement a wide range of features the abundance of instructions allows for handling various tasks such as Graphics processing networking and more this versatility makes Sisk processors suitable for systems requiring extensive functionality Advantage 3 backward compatibility Sisk processors often maintain backward compatibility with older software they can execute instructions that were used by previous generations of processor making it easier to upgrade to a new sysk processor without the need to rewrite all software this compatibility ensures a smoother transition and protects existing investments in software development now let's move on to the disadvantages of Sisk processors disadvantage 1 increased complexity the large number of instructions in syst processors makes them more complex and challenging to design and Implement each instruction requires Hardware implementation which can contribute to higher design and Manufacturing costs the complexity of Sisk processors necessitates meticulous planning and Engineering efforts disadvantage too inefficiency in simple tasks while Sisk processors excel at complex operations they may not be as efficient in performing simple tasks with a vast instruction set some instructions may be unnecessary for straightforward tasks for instance an instruction designed to add two numbers together may be Superfluous if the numbers are already in register leading to potential performance and efficiencies disadvantage 3 limited portability Sisk processors May face challenges in terms of portability and compatibility with different operating systems the diverse instructions that they offer might not be fully supported by all operating systems therefore an operating system designed for a specific Sisk processor May encounter compatibility issues when running on a different Sisk processor that lack support for certain instructions overall Sisk processors bring both advantages and disadvantages to the table their strength lies in their ability to handle complex tasks sufficiently and provide a wide range of features however they may exhibit less efficiency in simple tasks and face challenges in terms of design complexity and compatibility with certain operating systems now let's move on to risk risk stands for reduced instruction set computer risk processors are known for their simple instruction sets and straightforward addressing modes let's dive into the world of risk architecture and understand its key characteristics unlike their CIS counterparts risk processors employ A reduced number of instructions this Simplicity allows for faster execution and more efficient processing each risk style instruction occupies just one word in memory optimizing space utilization and enabling streamlined operations one notable advantage of risk processors is their speed risk instructions are executed faster with each instruction taking just one clock cycle this efficient execution contributes to improved performance and reduced processing times while the roots of risk computers can be traced back to the 1960s they initially faced overshadowing from the popularity of Sisk microprocessors Sisk processors were widely implemented by manufacturers and calculators video games stereos and various other devices however in the 1980s risk computers gained significant traction and have since been widely adopted nowadays risk processors can be found in a multitude of devices from smartphones and tablets to high performance servers risk architecture has permeated various Industries the Simplicity and efficiency of risk processors make them well suited for these devices delivering excellent performance while maintaining power efficiency the Advent of risk architecture has revolutionized Computing providing a viable alternative to the more complex Sisk processors by focusing on Simplicity an efficient instruction execution risk processors have become a Cornerstone of modern Computing technology now let's delve deeper into the risk architecture specifically focusing on how the risk processor is implemented using a hardwired control unit let's take a quick look at the block diagram of the risk architecture as you can see unlike the complex instruction set Computing architecture we covered so far risk architecture does not have a micro program control store or control memory the reason behind this is that risk instructions are designed to be simple and execute one instruction per clock cycle therefore there is no need for a control store instead the risk architecture relies on a hardwired control unit to produce control signals that regulate the processor's hardware one of the key features of risk architecture is its emphasis on using registers rather than memory registers are the fastest available memory Source in a processor they are physically small and are located on the same chip as the arithmetic logic unit in the control unit risk instructions operate on the operands present in the processor's registers which allows for faster and more efficient processing by utilizing registers risk processors can avoid frequent access to slower memory locations improving overall performance now let's talk about the concept of a hardwired control unit and risk architecture making an instruction hardwired means permanently implementing a function or operation in the instruction using connected circuits a each operation is defined and implemented as a hardwired circuit the hardwired control unit generates control signals based on the instruction being executed which in turn regulates the behavior of the processor's hardware components this allows for a streamline an efficient execution of instructions as each instruction is designed to execute in a single clock cycle so to summarize risk architecture emphasizes the use of registers instead of memory as registers provide the fastest available memory Source risk instructions operate on operands Within These registers making processing faster and more efficient additionally risk processors Implement a hardwired control unit which generates control signals to regulate the hardware components by hardwiring instructions each operation is defined using connected circuits enabling instructions to execute in a single clock cycle I hope this helps you understand the risk architecture now let's take a closer look at some of the notable risk processors that have made their Mark in the industry mips microprocessor without interlocked pipeline stages bips is a well-known risk processor architecture developed by mips Technologies it gained popularity due to its Simplicity and efficiency mips processors have been used in various applications including embedded systems gaming consoles and networking equipment spark scalable processor architecture spark is an open and scalable risk architecture developed by Sun Microsystems spark processors have been widely used in servers workstations and high performance Computing systems IBM power instruction set performance optimization with enhanced risk IBM power architecture is another notable example of a risk processor power processors are known for their high performance capability and have been used in IBM servers supercomputers and data centers Alpha also known as alpha axp alpha was a 64-bit risk processor archetype texture developed by digital Equipment Corporation Alpha processors were known for their exceptional performance and were used in deck's own workstations and servers risk 5 risk 5 is an open source risk processor architecture that has gained significant attention in recent years risk 5 offers a modular and extensible design making it popular for research education and even commercial applications arm architecture Advanced risk machines arm architecture is widely used in mobile devices tablets and embedded systems arm processors are known for their low power consumption making them suitable for battery-powered devices these are just a few examples of the many risk processors that have made an impact in the world of computing each architecture has its own unique features and strengths catering to different application domains whether it's the Simplicity and efficiency of mips the scalability of spark the high performance capabilities of IBM power the exceptional performance of alpha the openness of risk 5 or the power efficiency of arm risk processors continue to play a crucial role in modern computing now let's discuss the advantages and disadvantages of risk processors risk processors offer several advantages over Sisk processors let's take a closer look at some of these advantages Advantage 1 Simplicity risk instructions are simpler than CIS instructions which makes them easier to understand and implement this Simplicity contributes to better software development debugging and maintenance as programmers can focus on writing clean and efficient code Advantage 2 efficiency risk processors can be more efficient than Sisk processors due to their simplified instruction set without the need to decode complex instructions risk processors can achieve faster instruction execution leading to improved overall performance Advantage 3 Performance risk processors excel in performance as they can execute instructions one per clock cycle this parallelism allows for efficient utilization of Hardware resources and can result in higher instructions per second rates however like any architectural approach risk processors also come with with some disadvantages here we have few of them disadvantage one length risk programs can be longer than cisc programs because risk instructions are simpler and require more instructions to perform complex operations this can lead to larger program sizes and increased memory requirements this Advantage 2 cost designing and Manufacturing risk processors can be more expensive than cisc processors due to the need for a more complex Hardware implementation this increased cost can impact the availability and affordability of risk-based systems disadvantage 3 flexibility risk processors may be less flexible than Sisk process because they do not offer a wide range of instructions applications that require complex operations or a diverse instruction set may find risk processors less suitable risk processors offer a number of advantages over Sisk processors including Simplicity efficiency and performance however they also have some disadvantages such as the need for more instructions and the difficulty of processing complex instructions overall risk processors are a good choice for applications where Simplicity and efficiency are important such as embedded systems and mobile devices to summarize in this video we have explored the different classifications of microprocessors based on their instruction set architectures we have learned about risk and Sisk processors as well as other notable categories such as vliw a sick and fpga we have also discussed the advantages and disadvantages of each type of processor in general risk processors are simpler and faster than Sisk processors however Sisk processors are more flexible and can handle a wider range of tests the choice of which type of processor is best for a particular application depends on the specific requirements of that application for example if an application requires high performance then a risk processor may be a better choice however if an application requires a wide range of functionality then assist processor may be a better choice that brings us to the end of our exploration of risk and cisc architectures I hope you found this video informative and gained a better understanding of these powerful microprocessor designs if you have any questions or would like to learn more please leave a comment below don't forget to like and share this video with your friends and subscribe to omazingphysics for more exciting content thank you for watching and stay tuned for our next video [Music]

Channel: Ohmazing Physics

Views: 3,017

Keywords: RISC vs. CISC, Computer architecture, computer science, engineering, electronics, NPTEL, microprocessor, How does a computer work, Computer basics, Arm, Intel, IBM, CPU, RISC-V

Id: DqZGt-VRQTE

Length: 20min 31sec (1231 seconds)

Published: Mon Jun 26 2023