List of CPU Architectures

List Of CPU Architectures

The following is a list of notable CPU architectures.

All computers run using very low-level commands which do some very basic functions, such as reading data, writing data, jumping to addresses, and calculating basic arithmetic. (The complete list of commands that can be run by a CPU is known as that computer’s instruction set). Instruction sets are relatively small; most higher-order programming languages, such as C++, Ada, Fortran, or Visual Basic, must be compiled (or translated, or interpreted) into these low level commands in order for a program to run.

These low-level commands are run in a series of steps, which are synchronized with the computer’s clock. (One apt analogy would be an internal combustion engine. In an engine, the pistons, valves, and fuel systems must all run in a very synchronized manner, so likewise a computer runs – with precise timing dictating when instructions are fetched and executed, and when data is read and written. If an engine runs in a cycle: intake, compression, ignition, and exhaust; so does a computer's CPU: fetch, load, execute, write.)

CPU architects strive for designs that are compact and efficient, thus forcing many tradeoffs to be considered during design. A 32-bit architecture can move more data than a 16-bit architecture in each cycle (thereby making it faster), but the data bus is also twice as wide, which takes up more area on the limited space of a chip. Despite these challenges, continual advances in VLSI design have made it possible for computer processors to steadily grow exponentially more powerful over the past few decades.