Instructions (Computer Science): Difference between revisions
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A computer needs 1 instruction to run (OISC with subleq). It's possible but not fun. | A computer needs 1 instruction to run (OISC with subleq). It's possible but not fun. | ||
Each instruction is of a fix size. In [[FISC]], for example, each instruction is 2 bytes. Arguments on this instruction does not need to conform to a certain order (such as that dictated by the assembly language). | |||
= Suboperator = | |||
Some instructions have ''free bits'' in the instruction due to the fixed size. In this case, the free bits may be used as '''suboperators.''' This requires additional circuit on the [[ALU]]. | |||
In [[FISC]], for example, the ''not'' instruction only specify two registers (unlike the usual 3), so 2 bits are left free. | |||
[[Category:Computer Architecture]] | [[Category:Computer Architecture]] |
Revision as of 15:22, 15 April 2024
A computer needs 1 instruction to run (OISC with subleq). It's possible but not fun.
Each instruction is of a fix size. In FISC, for example, each instruction is 2 bytes. Arguments on this instruction does not need to conform to a certain order (such as that dictated by the assembly language).
Suboperator
Some instructions have free bits in the instruction due to the fixed size. In this case, the free bits may be used as suboperators. This requires additional circuit on the ALU.
In FISC, for example, the not instruction only specify two registers (unlike the usual 3), so 2 bits are left free.