Super Digga versions

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joachim
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Super Digga versions

Post by joachim »

While trying to look at the source of Super Digga (http://bbcmicro.co.uk/game.php?id=1583) I noticed that the game file is completely different to the one that was actually published in Electron User (https://archive.org/details/ElectronUse ... 1/mode/2up). The EU version is a typein-friendly format which uses the BASIC assembler, whereas the bbcmicro.co.uk version contains no assembly source and just CALLs some embedded machine code.

It would be nice to
  1. figure out and document where the bbcmicro.co.uk version came from, and
  2. archive both versions (the original magazine version seems to be available on 8bs EUD 88-2) and link them together as alternative versions.
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Rich Talbot-Watkins
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Re: Super Digga versions

Post by Rich Talbot-Watkins »

If you LOAD "DIGGA" and then type PAGE=PAGE+&800, you can see the main listing. Pretty much all the magazine type-ins on bbcmicro.co.uk are obfuscated in this way, and I honestly have no idea why. I'd prefer them all to be presented in their original form, although, in this regard I'm something of a purist, and would love if the disk images were a format which preserved the original protection and everything!
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lurkio
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Re: Super Digga versions

Post by lurkio »

As I recently implied in a post in another thread, many (probably most) of the games on bbcmicro.co.uk are derived from Mick's unofficial "30th Anniversary" DSD compilations. Mick's ethos when compiling the DSDs was to try to squeeze eighteen games onto every DSD. The downside of that is that he's sometimes had to go to some lengths to combine multiple files into one, which I suspect is what happened in the case of Super Digga.

But the upside is that Mick and Lee (and me, to a lesser exent) have put a lot of work into testing the games and painstakingly typing in instructions and listings, and debugging them when necessary, and compacting some of the originally tape-based games to get them to load from and save to disc, etc... I've tried to convey a sense of some of this behind-the-scenes work on the About page on bbcmicro.co.uk and in various posts scattered across Stardot.

The result is that some games might appear to be "obfuscated" in some way. But then the purpose of bbcmicro.co.uk was never to preserve original releases intact. It was to find a manageable and reasonably efficient process to get thousands of Beeb games online quickly, without having to find and upload each one manually (although the details (the metadata) for many of the games have been input manually -- largely by Lee).

The process isn't perfect, and I'm not always happy with the way some games end up being altered en route to being uploaded to bbcmicro.co.uk, but, so far, the positives seem to have outweighed the negatives. The original brief, which was to quickly get the bulk of the Beeb's game catalogue online on a user-friendly website, with as few errors and bugs as possible, seems to have been fulfiled. And, at the end of the day, there's only so much spare time that we can volunteer to spend on the archive, so we had to take a pragmatic approach. Nevertheless, we're always happy to receive suggestions or bug reports, etc.

:idea:
joachim
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Re: Super Digga versions

Post by joachim »

Ok, this time an actual bug report, again from one of the newly posted Electron User games: Shove Penny (http://bbcmicro.co.uk/game.php?id=1616) crashes after your second turn with "No room at line 530".

Even though it's shifted itself down to &E00, TOP is at &27E9 which is pretty tight for a MODE 2 game. My guess is that adding the memory shift routine made it just too long to fit.
Michael Brown
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Re: Super Digga versions

Post by Michael Brown »

Hi Thanks for the report.
The original game featured a shift routine which was not deleted after running, so I can only assume the original game would crash at some point as well.
I have amended the downloader to shift the game down to &D00 instead allowing extra space. Hopefully, that sorts it!

regards,
Mick.
Michael Brown
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Re: Super Digga versions

Post by Michael Brown »

Hi All,
Yes, with regard to the above. The adding of the instructions to some games from the mag listings was something I started doing more recently and not at the time of creating the discs. Therefore, due to disc space limitations with the amount of filenames, It was not always possible to create a separate file for the instructions and I had to do a sort of merge where the instructions run in at &1900 and then call a machine code downloader that shifts the game code (which is stored after the instructions) down to &E00 or wherever.

I too am not 100% happy with this arrangement, but it was a case of this way or no instructions and I think some of the games benefit from having their instructions.
In a perfect world we would just transfer the games from tape to disc and they would be left as they were and would run as they should. This is not the case with most games and some modification is needed for disc use. I have tried to keep the games as close to how they were intended, but with some, I have no choice but to add amendments.
Hopefully, what I have done does not distract you from how the games perform.

Finally, please, please, please try the games and if you find a fault with the game or what I have done to it, report it on this forum and I will sort a solution as soon as I can.

thanks,
Mick.
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