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From: Paul Brook <paul@codesourcery.com>
Subject: Re: [Qemu-devel] 16-bit (and 8-bit) emulation
Date: Sun, 15 Apr 2007 12:42:33 +0100
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To: qemu-devel@nongnu.org

On Sunday 15 April 2007 12:33, Stuart Brady wrote:
> On Sun, Apr 15, 2007 at 11:08:56AM +0100, Nigel Horne wrote:
> > Can qemu emulate 16-bit machines (286?)?
>
> None that I'm aware of.  Is there any particular need for 286 emulation?
> OTOH, it might be interesting to see some m68k system emulation.
>
> I've been working on an 8-bit machine, with some success.  The one thing
> that I'm not really sure about is bank switching (although I think I can
> just call cpu_register_physical_memory()).

It's probably easier to map all banks into a single large address space, and 
use the bank number as the high bits of the address. That way you can switch 
banks without having to flush everything.

gdb uses similar tricks to deal with multiple address spaces on DSPs.

Paul