Re: Future of ELKS

Chad Page
2004-05-21T03:39:23Z

On Fri, 21 May 2004, Stefan de Konink wrote:

> > > Hey, someone know if a 8086 is fast enough run emulators for those old
> > > 8-bit game consoles? 8)
> >
> > Nah. A 4.77MHz 8086 does not get a lot of work done. Say you want to
> > emulate a 2MHz 6502, such as the BBC Micro... this means you have about
> > two and a half cycles to emulate each 6502 cycle. Just not possible.

Yup... the memory access speed is *much* slower for instance.
When I was working on ELKS little tweaks which wouldn't be noticable on
even the Pentiums of the day - let alone today's HW - were *very*
noticable on the PC.

> Totally offtopic but I would like to know it. What if an entiere program
> gets preprocessed, lets say optimized to run on a 8086. So a program reads
> binary, disassembles, rewrites to 8086 code, reassembles and run.
> Or am I talking garbage :S (I thought emulators did a JIT thing...)

qemu does that on the fly - it usually outputs about 10
instructions per emulated one, in my experience. J. Meyer has stated that
an 2ghz Athlon 64 runs at about the speed of a 200mhz ppc in qemu, for
example. Might be possible to get a better code ratio against an 8-bit
system - Intel had direct code converters from 8080 code, but even then it
might be tricky. But you would also have to emulate the graphics
hardware, which challenges faster systems quite a bit!

It'd be interesting to emulate a high-density p-code system on an
8086 to fit more code into ELKS, but it'd likely be too slow in practical
use.

- Chad

> Btw. If a mirror of the hacked elks code is needed, please give a shout.
>
>
> Stefan
>
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