Reply to post: @Wilseus Re: I'm impressed

Every major OS maker misread Intel's docs. Now their kernels can be hijacked or crashed

defiler

@Wilseus Re: I'm impressed

You're right. There were (from memory - it's been a _long_ time) 16 basic operations, and each one could be run conditionally based on the status register (allowing you to inline a few instructions that you'd normally have to JMP over), and there was a flag to have the instruction _set_ the status registers too. It wasn't mandatory. So, whilst there were many permutations of these options, it all came down to 16 simple instructions (which was ideal for learning assembly).

Yep, all commercial ARMs had MUL, but I'm pretty sure I recall there being a debate whether they would at the time. The thinking was that it might be too CISC-y, and you could multiply in software. Compared to other instructions on the chip it took a long time too.

I miss my Archimedes.

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