microcode
Speech parts
1. microcode - Noun
2. microcode - Verb
Meaning
(computer science) coded instructions that are stored permanently in read-only memory
Source: WordNetSynonyms
Hypernyms
Examples
A CPU that uses microcode generally takes several clock cycles to execute a single instruction, one clock cycle for each step in the microprogram for that instruction.
An 8080 CPU loads the microcode from an RM03, RM80, or RP06 disk or magnetic tape and then starts the main processor.
As transistors became cheaper, horizontal microcode came to dominate the design of CPUs using microcode, with vertical microcode being used less often.
Because of its close relationship to the underlying architecture, "microcode has several properties that make it difficult to generate using a compiler."
Disk I/O was handled by multitasking at the microcode level.
Even late in the design process, microcode could easily be changed, whereas hard-wired CPU designs were very cumbersome to change.