The simplest way to examine the advantages and disadvantages of RISC architecture is by contrasting it with it’s predecessor: CISC (Complex Instruction Set. RISC and CISC Architectures – Difference, Advantages and . Disadvantages of CISC Architecture: Disadvantages of RISC Architecture. RISC and CISC are two architectures used for designing of Advantages of CISC Architecture Disadvantages of RISC Architecture.

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This architecture necessitates on-chip hardware to be continuously reprogrammed.

Addressing modes are the manner in the data advantqges accessed. The ease of microcoding new instructions allowed designers to make CISC machines upwardly compatible: CISC RISC It consists of a large set of instructions with advantaages formats Typically 16 to 64 bits per instruction It consists of small set of instructions with fixed format and these instructions are of register based instructions. The major characteristics of CISC architecture are It has a large number of instructions, typically from to instructions.

Every processor is built with the ability to execute a set of instructions for performing a limited set Many CISC architectures, read the inputs and write their outputs in the memory system instead of a register file.

RISC and CISC Architectures – Difference, Advantages and Disadvantages

The instruction set architecture is the part of the processor which is necessary for creating machine level programs to perform any mathematical or logical operations. Multiplying Two Numbers in Memory On the right is a diagram representing the storage scheme for a generic computer.

Processors having identical ISA may be very different in organization. Let us discuss these cosc architectures in brief and their difference.

The Advantages and Disadvantages of RISC and CISC | Vinod kadam……..

In order to avoid more interactions or to reduce access time, RISC processors are provided with multiple sets of registers with optimized register usage so that frequently accessed operands are remain in high-speed storage. As each instruction became more accomplished, fewer instructions could be used to implement a given task.


The design of the control unit is also simple due to the limited number of instructions. You are commenting using your WordPress. They provide a high level of abstraction, conciseness and power. It consists of a large number of general purpose registers, typically 32 to with split data cache for dsadvantages cache. Spends more transistors on memory registers.

To find out more, including how to control cookies, see here: The processor is controlled using microcoded control memory modern CISC processor also uses hardwired control.

Single-clock, reduced instruction only. As far as the processor hardware is concerned, there are 2 types of concepts to implement the processor hardware architecture. Because there are more lines of disadvwntages, more RAM is needed to store the assembly level instructions.

For instance, if we let “a” represent the value of 2: Typically, a large memory cache is provided on the chip in most RISC based systems. The speed of the operation can be maximized and the execution time can be minimized.

Therefore, aadvantages hardware and instruction set became complex with each generation of the processor. The processor is controlled cisd a hardwired control without control memory. It uses a variety of addressing modes, typically from 12 to 24 modes. To find multiplication of two numbers- One stored in location 1: Due to this one cycle instruction, execution of instructions carried at a faster rate compared with microinstructions on CISC processor.

The operand is a memory register where instruction applied. The major characteristics of CISC architecture are.


RISC processors require very fast memory systems to feed various instructions. Only load and store instructions have memory access. Join 19 other followers. Because, the large programs need more storage, thus increasing the memory cost and large memory ane more expensive. Hardware architecture may be implemented to be either hardware specific or software specific, but according to the application both cisf used in the required quantity.

The simplest way to examine the advantages and disadvantages of RISC architecture is by contrasting it with it’s predecessor: RISC does the opposite, reducing the cycles per instruction at the cost of the number of instructions per program Pipelining is one of the unique feature of RISC.

If the main memory is divided into areas that are numbered from row1: The per-chip cost snd reduced by this architecture that uses smaller chips consisting of more components on a single silicon wafer.

CISC – Advantages and disadvantages table in A Level and IB Computing

External memory access time is reduced by a larger number of registers. Transistors used for storing complex instructions.

CISC wnd involve very complex architectures, including a large number of instructions and addressing modes, whereas RISC designs involve simplified instruction set and adapt it to the real requirements of user programs.

He has 8 years of experience in Customer Support, Operations and Administration. This architecture uses less chip space due to reduced instruction set. However, the wdvantages unit can only operate on data that has been loaded into one of the six registers A, B, C, D, E, or F.