eric76 wrote:
Back for a moment with a bit more to add.
On the VAX computers, there was a level between the cpu and the assembly/machine language called microcode. You used microcode to define the assembly/machine language.
You couldn't write programs with the microcode, but you could conceivably create a single assembly/machine language instruction that did a lot of processing.
For example, with microcode you could create an assembly language instruction that would compute a Cyclic Redundancy Check on a block of data. I don't remember clearly, but I think that DEC may have had such an instruction on the VAX computers.
Microcode is still very much around - it's the 'cpu firmware' of x86 and x64 intel & amd processors. Complex functions and bug fixes, mostly. I'd also like to say that Arduinos use microcode, but I'm not sure people aren't just making a portmanteau of microCPU and programming code. I'll have to dig deeper...it's certainly not the high level stuff most are referring to when they use the term with arduinos. PIC processors, yes.
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