Date   : Thu, 30 Jan 1997 19:56:46 +0000
From   : "David Ralph Stacey" <drs1@...>
Subject: Re: BBC emulation (what else...)/coding help offer/etc.

Chris wrote:

> I'm trying to find ANY PC Beeb emulator that is capable of running the
> classic Exile. I run both Win95 and Linux. Here's the results:
>
> Xbeeb (0.3.6) -- Looks very promising. But running Exile bombs with "can't
> find $.ADFS in disk catalogue" or similar. And by bombs, I mean the whole
> program quits, not some "Not found" from the BBC. This occurs with "*RUN
> EXILEL"

Humm... This shouldn't be happening. I suspect that you're trying to
run Xbeeb
without XDFS. Basically, the XDFS ROM does some nasty things behind your back
to get things like Exile working. Quite a few games (eg. disc versions of
Pipeline, Spellbinder, Elite, etc) won't even load without it, and it does
silly things to make the emulator more stable. Make sure it's #define-d.

Even then, XDFS is a DFS emulator - it isn't supposed to cope with *ADFS
commands. Try running the 5.25 disc version instead - you'll need to
strip the
protection first though ;-)

Now you'll need to make the following change to src/Ops.h. In the Decimal
case of #define Adc add the logical and line to make the code look like this:

...
        Alo += vlo + CarryFlag; \
        if ( Alo >= 10 ) \
        { \
            Alo -= 10; \
            Ahi++; \
            Alo &= 0x0f; \
        } \
        Ahi += vhi; \
...

and recompile. This should get Exile (sort of) running under Xbeeb 0.3.6, but
the timers will be wrong.

Also you won't be able to load and save your position - you'll have to wait
for XDFS 0.90 for that - should be in the next release of xbeeb, but
if you're
desperate mail me and I'll send you a beta test version.

Hope this helps,

Dave Stacey - author of XDFS.