11 Lecture - CISC and RISC

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11 Lecture

CS501

Midterm & Final Term Short Notes

CISC and RISC

CISC (Complex Instruction Set Computing) and RISC (Reduced Instruction Set Computing) are two different types of computer processor architectures. CISC processors have a large and complex set of instructions, which can perform multiple operation


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Midterm & Finalterm Prepration
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  1. What does CISC stand for? A) Complex Instruction Set Computing B) Computer Instruction Set Code C) Compact Instructional System Computing D) None of the above Answer: A) Complex Instruction Set Computing What is the primary difference between CISC and RISC processors? A) CISC processors have a smaller instruction set than RISC processors B) RISC processors have a more complex instruction set than CISC processors C) CISC processors have a larger and more complex instruction set than RISC processors D) None of the above Answer: C) CISC processors have a larger and more complex instruction set than RISC processors Which type of processor architecture is better suited for mobile devices? A) CISC B) RISC C) Both architectures are equally suited for mobile devices D) Neither architecture is suited for mobile devices Answer: B) RISC Which of the following is an example of a CISC processor? A) Intel 80386 B) ARM Cortex-A53 C) IBM PowerPC D) All of the above Answer: A) Intel 80386 Which type of processor architecture is better suited for multimedia and gaming applications? A) CISC B) RISC C) Both architectures are equally suited for multimedia and gaming applications D) Neither architecture is suited for multimedia and gaming applications Answer: A) CISC Which type of processor architecture is known for its pipelining ability? A) CISC B) RISC C) Both architectures are equally known for their pipelining ability D) Neither architecture is known for its pipelining ability Answer: B) RISC Which type of processor architecture typically has a higher power consumption? A) CISC B) RISC C) Both architectures have the same power consumption D) It depends on the specific processor model Answer: A) CISC Which type of processor architecture is more commonly used in embedded systems? A) CISC B) RISC C) Both architectures are equally used in embedded systems D) Neither architecture is used in embedded systems Answer: B) RISC Which type of processor architecture is known for its emphasis on load/store instructions? A) CISC B) RISC C) Both architectures emphasize load/store instructions D) Neither architecture emphasizes load/store instructions Answer: B) RISC Which of the following is an example of a RISC processor? A) Intel Pentium B) Motorola 68000 C) MIPS R4000 D) All of the above Answer: C) MIPS R4000


Subjective Short Notes
Midterm & Finalterm Prepration
Past papers included

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  1. What is the basic principle behind the CISC architecture? Answer: CISC processors have a large and complex set of instructions, which can perform multiple operations in a single instruction. What is the main advantage of the RISC architecture over the CISC architecture? Answer: RISC processors have a simpler and more streamlined instruction set, which makes them faster and more efficient than CISC processors. How does the complexity of the instruction set affect the power consumption of a processor? Answer: A more complex instruction set generally requires more power to execute, which is why CISC processors tend to have higher power consumption than RISC processors. What are some of the common applications for CISC processors? Answer: CISC processors are often used in applications that require complex calculations and data manipulation, such as multimedia and gaming. How do RISC processors handle complex instructions that are not part of their instruction set? Answer: RISC processors can use software-based techniques such as microcode or emulation to handle complex instructions that are not part of their instruction set. What are some of the common applications for RISC processors? Answer: RISC processors are often used in embedded systems and mobile devices due to their lower power consumption and faster processing speeds. How does pipelining work in a RISC processor? Answer: Pipelining is a technique that allows a RISC processor to execute multiple instructions simultaneously by breaking down the instruction execution process into several stages. What is the role of the instruction decoder in a CISC processor? Answer: The instruction decoder in a CISC processor is responsible for translating complex instructions into a series of simpler micro-instructions that can be executed by the processor. How does the size of the instruction cache affect the performance of a RISC processor? Answer: A larger instruction cache can improve the performance of a RISC processor by reducing the number of instruction fetches from memory. What are some of the common trade-offs between CISC and RISC architectures? Answer: CISC processors tend to be more versatile and better suited for complex applications, but they also tend to have higher power consumption and slower processing speeds than RISC processors. RISC processors, on the other hand, are more specialized and better suited for embedded systems and mobile devices, but they may struggle with more complex applications.

CISC (Complex Instruction Set Computing) and RISC (Reduced Instruction Set Computing) are two different types of processor architectures. CISC processors have a large and complex set of instructions that can perform multiple operations in a single instruction, while RISC processors have a simpler and more streamlined instruction set that focuses on performing basic operations quickly. CISC processors were developed in the 1970s and 1980s, and were designed to support a wide range of operations and applications. They were often used in high-performance computing applications, such as multimedia and gaming. CISC processors can execute complex instructions in a single cycle, which makes them well-suited for applications that require complex calculations and data manipulation. On the other hand, RISC processors were developed in the 1980s and were designed to be more efficient than CISC processors. RISC processors have a simpler instruction set that focuses on performing basic operations quickly. They are often used in embedded systems, mobile devices, and other applications where power consumption is a concern. RISC processors can execute basic instructions quickly, which makes them well-suited for applications that require fast processing speeds. One of the key differences between CISC and RISC processors is the way they handle instructions. CISC processors use microcode to translate complex instructions into simpler micro-instructions, while RISC processors use a simpler instruction set that is easier to decode and execute. This makes RISC processors faster and more efficient than CISC processors, but also less versatile. Another difference between CISC and RISC processors is their power consumption. CISC processors tend to have higher power consumption than RISC processors because they require more power to execute complex instructions. RISC processors, on the other hand, are designed to be more power-efficient, which makes them well-suited for mobile devices and other applications where power consumption is a concern. Overall, both CISC and RISC processors have their own strengths and weaknesses, and are suited for different types of applications. CISC processors are well-suited for applications that require complex calculations and data manipulation, while RISC processors are well-suited for applications that require fast processing speeds and low power consumption. As technology continues to evolve, it will be interesting to see how these two processor architectures continue to develop and compete with each other.

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