Difference between revisions of "Instruction"
From Computer History Wiki
m (+cat) |
m (better cat) |
||
| Line 5: | Line 5: | ||
{{semi-stub}} | {{semi-stub}} | ||
| − | [[Category: | + | [[Category: CPU Basics]] |
Revision as of 16:11, 15 December 2018
An instruction is, at the highest level of abstraction, the smallest unit of computation which a programmer can direct the CPU to perform.
In more practical terms, the CPU operates by fetching items from main memory; each item contains a single directive for the CPU (e.g. a the contents of one register to another, or move a unit of data from a register, to main memory) - those items are instructions. (An instruction is usually a word, but on some CPUs, multiple instructions could be packed in each word, while on others, some instructions took multiple words.)
