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Risc/cisc

Advantages / Disadvantages of Risc and Cisc and which is better and why? also which one would you choose & why?

thanks
Original post by ShahbazKHAN
Advantages / Disadvantages of Risc and Cisc and which is better and why? also which one would you choose & why?

thanks


Both are respectable but i would go with RISC because i am old (22)
Just a few things quickly thought up.

RISC advantages:

RISC has less instructions, so it is easier to memorise the instruction set
RISC's instructions are generally more versatile, meaning that there is more reason to memorize each one and you don't have to go through a massive code reference to find that one mnemonic
RISC instructions generally have simpler objectives. As a result, they tend to be quicker

RISC Disadvantages:

Many RISC instructions need to be used to achieve something reasonably complex which a CISC architecture may have a single instruction. Makes code a lot longer

Examples: 6502, Z80


CISC advantages:
A lot of instructions means a lot can be achieved with just one instruction

CISC disadvantages:
A ton of different opcodes to learn
Some instructions are much slower than others, so it less easy to predict speed due to disparity in instruction speed
Some instructions have a very large scope, so they can be a lot harder to understand

Examples : x86
Original post by TercioOfParma
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Thanks but you forgot, which one is better and why? and why which one would you use and why? thanks
Original post by ShahbazKHAN
Thanks but you forgot, which one is better and why? and why which one would you use and why? thanks


Each are good for different situations.

RISC is generally better for embedded systems and smaller, lower power computers since they have less to store and it hence decreases the size of required on chip storage as well as somewhat mitigating the effects of instructions being too slow on their own.

CISC is very useful for general use machines that are generally not specialised but are required to have a significant amount of functionality, as it means they can "jack of all trades, master of none" the whole thing.

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