Experimental Acorn Bbc Model B Emulator.


frutbunn

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I've started playing with the idea of porting over the excellent BeebEm emulator to my cool new GP2x. This is just a 'proof of concept' so to speak, but I'm quite happy with the results so far!

There is no sound as yet, the timing is non-existent and you can only run the one provided disc image (keys are hardwired), but if anyone's interested in giving it a try on their machine you can get the executable and source here:

http://beebem-unix.bbcmicro.com/download/beebem.tar.gz

To run, please extract and copy the created 'beebem' directory to the root directory (/) of your sd card (/mnt/sd/ in GNU/Linux for FTP etc) otherwise it won't run (all directories/filenames are hardwired for now - consider devel snapshot - run at own risk etc).

Oh, and try to get to level 5, it may be harder than you think! B)
 
subcon959 posted on Dec 5 2006 at 09:29 PM said:
The criticalbeeb port of bem already exists and is further along but the more people working on a decent beeb emu the better!

I don't know how to respond to that, I really don't :lol:
 
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Fru.T Bunn posted on Dec 5 2006 at 09:49 PM said:
subcon959 posted on Dec 5 2006 at 09:29 PM said:
The criticalbeeb port of bem already exists and is further along but the more people working on a decent beeb emu the better!

I don't know how to respond to that, I really don't :lol:
The release thread for criticalbeeb is here:

http://www.gp32x.de/board/index.php?showtopic=32438&hl=

Have a look, grab the source, whatever :)
 
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critical posted on Dec 5 2006 at 10:00 PM said:
Fru.T Bunn posted on Dec 5 2006 at 09:49 PM said:
subcon959 posted on Dec 5 2006 at 09:29 PM said:
The criticalbeeb port of bem already exists and is further along but the more people working on a decent beeb emu the better!

I don't know how to respond to that, I really don't :lol:
The release thread for criticalbeeb is here:

http://www.gp32x.de/board/index.php?showtopic=32438&hl=

Have a look, grab the source, whatever :)

I've seen it already, after all it was me that ported it from Windows to SDL! (why am I always crap at this sort of thing?)
 
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Fru.T Bunn posted on Dec 5 2006 at 10:21 PM said:
critical posted on Dec 5 2006 at 10:00 PM said:
Fru.T Bunn posted on Dec 5 2006 at 09:49 PM said:
subcon959 posted on Dec 5 2006 at 09:29 PM said:
The criticalbeeb port of bem already exists and is further along but the more people working on a decent beeb emu the better!

I don't know how to respond to that, I really don't :lol:
The release thread for criticalbeeb is here:

http://www.gp32x.de/board/index.php?showtopic=32438&hl=

Have a look, grab the source, whatever :)

I've seen it already, after all it was me that ported it from Windows to SDL! (why am I always crap at this sort of thing?)
I *did* wonder from your download url ;) I'm only reading and posting from my mobile phone at the moment, so didn't investigate further.

I guess my question is now: what's the direction you're looking to take from here? I'd gladly work with you or help towards improving the current state of beeb emulation on the gp2x.

I have a virtual keyboard system almost finished for criticalbeeb (thanks to painstaking work from rooster). After that, I'm not sure I'd work on it any more due to other commitments.

It'd be very useful to look at a 6502 asm core for it, perhaps basing it on ones from extant NES emulators.

I suppose I'm not sure of your motivation with this at the moment, that's all... maybe it's just because. And why not? ;)
 
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"I suppose I'm not sure of your motivation with this at the moment, that's all... maybe it's just because. And why not?"

I just like the BBC games! :)

But sharing source code is so much harder these days :(

Sorry to be snappy and all that (I didn't mean to post today [and today is a bad day for me], it just all came together and worked, and I just wanted to share it).
 
Gruntfuggly posted on Dec 6 2006 at 03:13 PM said:
Err - KoH - have you not tried the Chuckie Egg conversion for the GP2X? It's pretty much perfect - no need to emulate it...

http://www.gp2x.de/cgi-bin/cfiles.cgi?0,0,0,0,35,1823
It's not bad but there's an annoying glitch in the jumping.

Plus it's always nice to play the real thing :) (Well, emulated real thing lol)
 
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Gruntfuggly posted on Dec 6 2006 at 03:13 PM said:
Err - KoH - have you not tried the Chuckie Egg conversion for the GP2X? It's pretty much perfect - no need to emulate it...

http://www.gp2x.de/cgi-bin/cfiles.cgi?0,0,0,0,35,1823


BBC version is the best !!!



+ i dont actually own a gp2x at the moment, but seeing this bbc emulator will only hurry me up getting another one :D


any chance we can see this on the gp32 aswell ;)
 
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KoH - it is identical to the BBC version...

Fru. T Bunn - looks really good - got to level 4 but my batteries died. Speed is impressive - it seems to be a fair bit faster than I remember it - I certainly can't fire quick enough on the challenge stage! Maybe I'm just getting old...

Looking forwards to the next release!
 
Gruntfuggly posted on Dec 6 2006 at 08:19 PM said:
KoH - it is identical to the BBC version...

Fru. T Bunn - looks really good - got to level 4 but my batteries died. Speed is impressive - it seems to be a fair bit faster than I remember it - I certainly can't fire quick enough on the challenge stage! Maybe I'm just getting old...

Looking forwards to the next release!

Yeah, the timing isn't regulated and with the GP2x running flat out at 200Mhz, and the video updating at 25fps, I'm getting + 12% to the speed of an actual BBC B! I can improve video performance, so hopefully there will be enough left over for sound support. We may win yet! :)
 
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I guess my question is now: what's the direction you're looking to take from here? I'd gladly work with you or help towards improving the current state of beeb emulation on the gp2x.

I have a virtual keyboard system almost finished for criticalbeeb (thanks to painstaking work from rooster). After that, I'm not sure I'd work on it any more due to other commitments.

It'd be very useful to look at a 6502 asm core for it, perhaps basing it on ones from extant NES emulators.

I believe you're moving house at the moment? I did that last year, what a huge mental pain it was. I wish you luck with your move!

This GP2x version of BeebEm is actually based on a much older version of BeebEm (as we will probably only have the speed for the BBC B emulation), so I'll need to harmonise it with more current versions. After that its speed needs to be regulated. Sound's going to be a pain.

Once I get a bit further along we could probably put everything from both versions together as one package. Is there a link to the virtual keyboard code somewhere?

I'd like to keep the code for this as generic as possible (at least initially), so hopefully it can be used for other future platforms without the overkill of porting the whole SDL/UNIX version every time.

Using the Dzz tutorial I've put together a simple 4 bit colour depth frame buffer, and it should be quite easy to modify the video code for that. But I'll stick with SDL for now and keep everything as portable as possible.

If we mess about with the emulator core too much I think we may break a lot of compatibility with games. This first initial experiment was just really to see if it's do-able with the current (well it's actually an older BBC B only) 6502 emulator core on the GP2x at 200Mhz.

(Oh and sorry if I snapped at you in a previous post. Yesterday was a really shitty day for me...)
 
i love the bbcb and its always nice to see people willing to work on an emulator, i reccomend you putting your head together with critical that chap knows his stuff :)

anyways good luck.
here's to repton, dunjunz, pod and a heap of other games i used to love.
 
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