The Archimedes BBC Emulator
Acorn realised that if the Archimedes had a level of compatibility with
the earlier BBC machines it would help continue the tradition of Acorn
computers in schools. However technically the Archimedes is very different
to the BBC. The only real similarity is that the original BBC graphics
modes have been provided in addition to the enhanced Archimedes modes.
Arm BBC Basic is also provided with the Archimedes and thats merely an
update on the original BBC Basic. Still what the Archimedes needed was a
full blown emulator so that actual BBC software could be run. The Arm chip
has practically nothing in common with the 6502 and therefore software
emulation was required. A 32bit Arm chip would surely be capable of
emulating a 6502 at some speed. In fact it's fair to say that the emulation
is running at speeds equal to the BBC in many areas. However Mode 7 is not
one of them. This is definitely the weakest part of the emulator speed
wise. Its too slow and text ripples as it scrolls. However at least it has
Mode 7. The Electron although broadly similar to the BBC has a total
absence of Mode 7 and therefore it could be said that the Archimedes' BBC
emulator is superior to the Electron when it comes to BBC compatibility.
Which is rather an insult to the Electron when you think about it. Of
course the most important question of all is actual software
The more sophisticated the games the less likely they are to work. The
higher the percentage of the game that is written in Basic the more likely
they are to work. I'd make a guess and say generally about one in ten
games work. Thats of course the games I have which are unprotected and on
ADFS disks which may not represent the level of compatibility fairly.
In my experience there is a very high level of compatibility as most of
the educational titles I have are written in almost total Basic. In fact
some run in the Archimedes native Arm Basic.
3.8-Bit Software issues.
All the ADFS issues I have run without problems apart from one or two
programs. As mentioned above Mode 7 is slow but acceptable.
The emulator does provide for ROM images but I must admit I haven't tried
loading them. So it would be wrong to comment. The manual states that many
ROM images will work so I'll take their word for it. You can even create
launchable conversions. You can design a View icon for example and once
double clicked will load the emulator and rom image and start them
5.Application and utils.
Better compatibility than games. Applications tend to be more flexible
with memory and filing systems. So a lot of stuff does work.
Best of all the emulator is free and supplied with the computer. Well my
A3010 came with it. Theres also a tube emulator which uses the Archimedes
for input/output tasks etc and the tube emulator for 6502 code etc. It
works but just like connecting a 2nd processor to a normal BBC
compatibility is reduced and therefore you double your compatibility
problems with normal BBC software.