From 5ba5ef0e3899dcfb885563a9f557ca89e3ab2fab Mon Sep 17 00:00:00 2001 From: thomasabishop Date: Fri, 15 Mar 2024 09:10:04 +0000 Subject: [PATCH] Autosave: 2024-03-15 09:10:04 --- zk/Instruction_set_architectures.md | 53 +++++++++++++++-------------- 1 file changed, 28 insertions(+), 25 deletions(-) diff --git a/zk/Instruction_set_architectures.md b/zk/Instruction_set_architectures.md index ceb48a4..16314cb 100644 --- a/zk/Instruction_set_architectures.md +++ b/zk/Instruction_set_architectures.md @@ -20,9 +20,9 @@ tags: [CPU] ## Architecture is logical not physical -> Note that this is a logical architecture rather than a physical architecture. -> Like ISA processors may work very differently on the hardware level whilst -> still adhering to the same ISA +The "architecture" of an ISA is logical rather than physical, i.e processors +that share an ISA may work very differently on the hardware level whilst still +adhering to the same instruction set. ## ARM and x86 @@ -31,34 +31,37 @@ introduced by Intel but are also made by AMD. ### x86 -The name stems from Intel's internal naming conventions - every new processor -they introduced would have a letter designation ending with "86". Later they -would adopt names such as "Pentium", "Celeron" etc. Regardless, these processors -still fall under the "x86" family. +- First introduced by Intel but also made by AMD. -Over time, new instructions have been added to the x86 architecture but they all -maintain backwards compatibility with preceding generations. +- Name stems from Intel's internal naming conventions - every new processor they + introduced would have a letter designation ending with "86". Later they would + adopt names such as "Pentium", "Celeron" etc. Regardless, these processors + still fall under the "x86" family. -There have been different, successive generations of x86 corresponding to their -[word-size](Signed_and_unsigned_numbers.md): 16-bit, 32-bit, 64-bit. Word size -here just means how many bits the processor can work with at a time. +- Over time, new instructions have been added to the x86 architecture but they + all maintain backwards compatibility with preceding generations. -A 34-bit processor can operate on values that are 32 bits in length. This means -it has 32bit [[CPU_architecture#registers|registers]], a 32-bit data -[[Bus|bus]], a 32-bit address bus and so on. +- There have been different, successive generations of x86 corresponding to + their [word-size](Signed_and_unsigned_numbers.md): 16-bit, 32-bit, 64-bit. + Word size here just means how many bits the processor can work with at a time. + A 34-bit processor can operate on values that are 32 bits in length. This + means it has 32bit [[CPU_architecture#registers|registers]], a 32-bit data + [[Bus|bus]], a 32-bit address bus and so on. -AMD introduced the first 64-bit processor, not Intel but they later caught up. A -64-bit x86 processor is often referred to as _x64_ or _x86-64_. +- AMD introduced the first 64-bit processor, not Intel but they later caught up. + A 64-bit x86 processor is often referred to as _x64_ or _x86-64_. ### ARM -Whilst x86 processors dominate the personal computer and server space, on mobile -a different instruction set architecture predominates: ARM. The ARM company -develops the architecture and standard which it licenses it to other companies -to implment. +- x86 processors dominate the personal computer and server space -They are preferred on mobile because they have reduced power consumption and -lower costs compared to x86. +- On movile devices ARM ISA predominates -With ARM processors the processor is on a single chip that contains the CPU as -well as memory and other hardware. +- The ARM company develops the architecture and standard which it licenses it to + other companies to implement. + +- Preferred on mobile because they have reduced power consumption and lower + costs compared to x86. + +- The processor is on a single chip that contains the CPU as well as memory and + other hardware.