The programmer-visible instructions; examples include ARM, RISC-V and x86.
The ISA defines instructions, registers, addressing modes and memory model. RISC (ARM, RISC-V) uses simple fixed-length instructions; CISC (x86) has complex ones. Compilers target the ISA; binary compatibility depends on it.
ARM Thumb-2 mixes 16 and 32-bit instructions for code density.
An instruction set architecture is the contract between hardware and software, so choosing one affects tools, performance and licensing.
The programmer-visible instructions; examples include ARM, RISC-V and x86.
An instruction set architecture is the contract between hardware and software, so choosing one affects tools, performance and licensing.
RISC uses simple, uniform instructions that are easy to pipeline. CISC uses complex instructions that can do more work per instruction but are harder to implement efficiently.
Not alone. The microarchitecture, clock speed, caches and compiler all influence performance, while the ISA sets the interface.
Typical applications include choosing ARM for a phone SoC because of its ecosystem, selecting RISC-V for a custom microcontroller to avoid licence fees and porting firmware from one architecture to another.
Study "CPU architecture" first (topic 56 of 104 in Electronics & Embedded). It covers the groundwork this topic builds on.
Load/store architecture. Instruction encoding. Extensions like SIMD.
ARM Thumb-2 mixes 16 and 32-bit instructions for code density.
The next topic is "Pipelining", which builds directly on this one.
It is classed as Intermediate in Electronics & Embedded (topic 57 of 104). It is an intermediate topic. Work through the beginner topics in Electronics & Embedded first.
Want to practise? Open the interactive course for quick checks, quizzes, simulations and progress tracking.