Computer Architecture Basics:

Some of computer architecture at companies such like AMD and Intel uses more fine distinctions:

• Macro architecture- this is an architectural layer that are more abstract than micro architecture, for example. ISA
• ISA (Instruction Set Architecture) -it's already defined above
• Assembly ISA - it is a smart assembler can convert an abstract assembly language common to a group of machines into slightly different machine language for different implementations
• Programmer Visible Macro architecture- it is higher level language tools like as compilers may define a consistent interface or contract to programmers by using them, abstracting differences between UISA ,underlying ISA, , and micro architectures for example. The C, C++, or Java standards describe different Programmer Visible Macro architecture - even though in practice the C micro architecture for a specific computer includes
• UISA (Microcode Instruction Set Architecture) -it is a family of machines having different hardware level micro architectures may share a common microcode architecture, and therefore a UISA.
• Pin Architecture -it is a set of functions that a microprocessor is likely to provide, from the point of view of a hardware platform For example. FERR/IGNNE ,the x86 A20M, or FLUSH pins, and the messages that the processor is likely to produce after completing a cache invalidation so that external caches can be invalidated. Pin architecture functions are more supple than ISA functions - external hardware may adapt to changing encodings, or changing from a pin to a message - but the functions are expected to be provided in successive implementations even if the way of encoding them changes.