Antagonists and The Secret of Arendarvon Castle

want to request software or documentation that you can't find online? post in here!
iamaran
Posts: 160
Joined: Tue Mar 14, 2006 8:08 pm

Antagonists and The Secret of Arendarvon Castle

Postby iamaran » Tue Jan 31, 2012 4:40 pm

Has anyone come across The Antagonists and/or The Secret of Arendarvon Castle? They are listings from books of the same name published by Addison Wesley Productions in 1985.

The books were available for several platforms and were seemingly available with or without a cassette.

Thanks.

iamaran
Posts: 160
Joined: Tue Mar 14, 2006 8:08 pm

Re: Antagonists and The Secret of Arendarvon Castle

Postby iamaran » Mon Feb 02, 2015 9:14 pm

Scans of The Secret of Arendarvon Castle have been located, but somehow I don't think I'll be typing it in any time soon...

https://plus.google.com/photos/+ArendRensink/albums/5631330469099306449

User avatar
leenew
Posts: 3253
Joined: Wed Jul 04, 2012 3:27 pm
Location: Doncaster, Yorkshire

Re: Antagonists and The Secret of Arendarvon Castle

Postby leenew » Mon Feb 02, 2015 10:52 pm

Wow! That makes Infocom seem positively stingy with their additional material!
Looks cool 8)
Who's typing it in then? Or even better - who's got the cassette? :D
Lee.

User avatar
richardtoohey
Posts: 3353
Joined: Thu Dec 29, 2011 5:13 am
Location: Tauranga, New Zealand

Re: Antagonists and The Secret of Arendarvon Castle

Postby richardtoohey » Mon Feb 02, 2015 11:06 pm

They have helpfully split up the typing into suggested 1.5 hour chunks, one for every day for a week. :shock:

duikkie
Posts: 2509
Joined: Fri Feb 07, 2014 3:28 pm

Re: Antagonists and The Secret of Arendarvon Castle

Postby duikkie » Tue Feb 03, 2015 6:11 am

it a gamble to read what you read and to guess what to type in :)

leenew wrote:Wow! That makes Infocom seem positively stingy with their additional material!
Looks cool 8)
Who's typing it in then? Or even better - who's got the cassette? :D
Lee.

User avatar
lurkio
Posts: 973
Joined: Tue Apr 09, 2013 11:30 pm
Location: Doomawangara
Contact:

Re: Antagonists and The Secret of Arendarvon Castle

Postby lurkio » Wed Feb 04, 2015 11:53 pm

I actually tried typing a bit of this in :shock: : the decoder program and a few lines of DATA.

Line 1010 and lines 1040-1100 are all verified by the error-detecting checksum routine. (To see that, delete lines 1020 and 1030 (and then optionally renumber the remaining data lines to close the gap left by the deleted lines, so that 1040 becomes 1020, and 1050 becomes 1030, etc.).)

The DATA lines that fail the checksum test (1020-1030) give no clue as to why -- I mean, I can't tell which characters are wrong in some cases -- although in other cases it's obvious that a char is fuzzy and badly scanned, but then it's not at all clear what it should actually be! Aaargh!

(Plus, there's the curious incidence of n_code%.)

Code: Select all

40 RESTORE
50 PROCinit
60 add%=beg%
70 REPEAT
80 PROCnew_line
90 REPEAT
100 byte%=FNnext_byte
110 sum%=sum%+byte%
120 PROCadd_byte(byte%)
130 UNTIL line$=""
140 PROCchecksum
150 UNTIL add%>end%
160 END
180 DEF PROCinit
190 REM VDU 15
200 READ line%,in_bas%,n_code%,nob%
210 READ out_bas%,beg%,end%
220 ENDPROC
240 DEF PROCnew_line
245 REM P. "PROCnew_line"
250 READ line$
260 code%=0
270 check%=FNnext_byte
280 sum%=0
290 line%=line%+10
300 PRINT line%
310 ENDPROC
330 DEF PROCchecksum
340 IF code%=1 AND sum% MOD out_bas%=check% THEN ENDPROC
350 PRINT"Checksum error in line ";line%
360 END
370 ENDPROC
390 DEF PROCadd_byte(byte%)
400 IF nob%=1 THEN 440
410 ?add%=byte% DIV &80
420 byte%=byte% MOD &80
430 add%=add%+1
440 ?add%=byte%
450 add%=add%+1
460 ENDPROC
480 DEF FNnext_byte
490 LOCAL char%,byte%
500 REPEAT
510 char%=FNnext_char
520 code%=in_bas%*code%+char%
525 REM P. code%
530 UNTIL code%>=out_bas%
540 byte%=code% MOD out_bas%
550 code%=code% DIV out_bas%
555 REM P. code%
560 =byte%
580 DEF FNnext_char
590 LOCAL char$
600 REPEAT
610 char$=LEFT$(line$,1)
615 REM P.char$
620 line$=MID$(line$,2)
630 UNTIL char$<>" "
640 IF char$<"A" THEN =ASC(char$)-48 ELSE =ASC(char$)-55
1000 DATA 1000,36,29,1,257,18057,18631
1010 DATA 001F K8F5 8FF8 FP8F Z8G9 FK8T FJUG OVHK ZJ4Z NN0E UBE8 BE37
1020 DATA 03YP 3RZG 33MI S7ZK U37O POYN 4V63 S3G3 3PIF 54MG B0YX 2DT2
1030 DATA 0L4A 22E2 U455 MCUR VQ9T BHZ0 8WXZ CWBE THQP X6DD 20YS YG5Q
1040 DATA 0FSQ 5T9S SU3D XB39 6WEA 3FI4 ER6G HICT RT7E X3S6 HK2W 533A
1050 DATA 0DPC EHLD ZC4U RUAF 87PS U3ZC VRO7 V2YG LOBK P5HU GCEA Z2JV
1060 DATA 0CYV D958 6HC2 7FE3 P3Q9 5CNM 23FO IO7H WZ7J KH0D ZB3V 7FSO
1070 DATA 05WT FZDL ZO26 RU71 KH0L 4J4M 5WNE 7FL7 RZZZ 6IZI AEXJ DD7M
1080 DATA 01EH 3GZV 1IGZ 9L7Q 6LNM 01Q2 1HWX 0EOC OAFV SJ87 F2ES UIOB
1090 DATA 04HG B3J7 7FX0 M7QY LD23 FMJK AJRK IF7P M10L VZGA DFHE THWP
1100 DATA 0KC3 FO4E R7GH ICN6 Q6MN 7AKH IZD4 NTQ6 KN7Q KHIZ D4NS QDO2
Decoder.png
DATA.png

User avatar
lurkio
Posts: 973
Joined: Tue Apr 09, 2013 11:30 pm
Location: Doomawangara
Contact:

Re: Antagonists and The Secret of Arendarvon Castle

Postby lurkio » Tue Feb 24, 2015 12:09 am

The Secret Of Arendarvon Castle can now be played online. Click here to play online. (The game takes a little while to initialise.)

I contacted Arend Rensink, the original author of the book The Secret of Arendarvon Castle, and he kindly sent me some higher-quality scans and OCRs of the listings from the book. Lee and I have now checked and input the listings, and the game seems to work (in BeebEm at least).

I've attached an SSD here. It should be seen as a work in progress because I had to tinker with the main BASIC program before it would run: it was bombing out with a "No room" error, so I compressed it (removed REMs and spaces; concatenated lines; shortened variable names; preferred resident integer vars; etc.). It's my compressed version that appears on the disc-image as $.AREND. (There's also an older, larger, less compressed version called O.AREND, which you can switch to if you find that my compression has accidentally introduced bugs.)

    AREND_fix01.zip
    SSD disc-image of the game The Secret Of Arendarvon Castle for use in the BeebEm emulator. EDIT March 2017: fixed LOAD/SAVE bug. (Previous, buggy version of .SSD was downloaded 83 times. Oops.)
    (36.5 KiB) Downloaded 6 times
Please let me know if you have any problems running the game.

Just in case anyone's interested and finds them useful, the disc-image above includes BASIC-program versions of most of the listings from the book. Additionally, here are all the listings from the book as plain text files:

    listings.zip
    Plain-text versions of the listings from the book The Secret Of Arendarvon Castle
    (33.48 KiB) Downloaded 82 times

Arend sent me some interesting background info on the game and the book:

Arend Rensink wrote:... The book came out in a transitional period where it started to be less usual to have to type in your own programs. At some point you could buy a tape at some extra cost, but AFAIK that never got off the ground ...

... this was one of a set of books, each targeted at another of the many home computers that were around in the first half of the eighties. Besides the BBC Micro edition, I still have copies for the ZX Spectrum, Apple II and IPM PC (!) lying around; we also covered the Commodore 64, and maybe more that I forgot ...

The books were all the same [but] the encrypted [data, much of which] is ... a kind of bytecode avant la lettre ... is ... different from one computer to the next. That's really a pity, for it means that your work will not be reusable [on non-Beeb machines]. I suspect it might have something to do with memory layout differences, but I do not remember ...
lurkio wrote:Were you inspired to create the ALADIN bytecode by Infocom and the way they constructed their games (using the virtual "Z-machine")? Or was ALADIN an independent invention?

It was independent; in fact, this is the first time I've heard of the Z-machine at all. Yes, I agree that it looks like essentially the same idea, and clearly they were there before. Well, in my defense I can claim that literature research was somewhat more cumbersome back then...

... I developed and programmed the game (including the game engine) and wrote all of the text of the book. All drawings and graphical designs are by Bert van der Veen ...

For me, this was an internship at a small company (omikron). The other authors ["Hal Renko & Sam Edwards"] are fake identities that were used for more software-related books at the time.


Many thanks to Arend for helping me bring his game back to the Beeb!

    screenshot.png
    In-game screenshot of The Secret Of Arendarvon Castle


    arendarvon 000.jpg
    Scan of the front cover of the Beeb version of the book of The Secret Of Arendarvon Castle
Last edited by lurkio on Wed Mar 01, 2017 7:16 pm, edited 9 times in total.

User avatar
richardtoohey
Posts: 3353
Joined: Thu Dec 29, 2011 5:13 am
Location: Tauranga, New Zealand

Re: Antagonists and The Secret of Arendarvon Castle

Postby richardtoohey » Tue Feb 24, 2015 12:55 am

lurkio wrote:Lee and I have now checked and input the listings
=D>

Must have been some amount of work!

And thanks for the interesting write-up. I'm not an adventure player myself but good to read about restoration efforts and also how things were done BITD.

User avatar
lurkio
Posts: 973
Joined: Tue Apr 09, 2013 11:30 pm
Location: Doomawangara
Contact:

Re: Antagonists and The Secret of Arendarvon Castle

Postby lurkio » Tue Feb 24, 2015 8:06 pm

richardtoohey wrote:
lurkio wrote:Lee and I have now checked and input the listings
=D> Must have been some amount of work!

Thanks, Rich. It would have been much worse if we'd been typing everything in from scratch, checksums or no checksums! But as it was, the fact that we had OCRs to work with helped a lot, even though we still had to correct loads of errors (which is where the checksum system actually did come into its own).
Last edited by lurkio on Tue Feb 24, 2015 10:14 pm, edited 1 time in total.

iamaran
Posts: 160
Joined: Tue Mar 14, 2006 8:08 pm

Re: Antagonists and The Secret of Arendarvon Castle

Postby iamaran » Tue Feb 24, 2015 9:58 pm

Thank you. I look forward to downloading it.

iamaran
Posts: 160
Joined: Tue Mar 14, 2006 8:08 pm

Re: Antagonists and The Secret of Arendarvon Castle

Postby iamaran » Thu Apr 23, 2015 10:24 pm

Scans of 'The Antagonists' have been sent to me if anyone fancies a challenge...

iamaran
Posts: 160
Joined: Tue Mar 14, 2006 8:08 pm

Re: Antagonists and The Secret of Arendarvon Castle

Postby iamaran » Wed Oct 07, 2015 8:18 pm

I am currently sorting The Antagonists. Soon...

iamaran
Posts: 160
Joined: Tue Mar 14, 2006 8:08 pm

Re: Antagonists and The Secret of Arendarvon Castle

Postby iamaran » Sun Nov 29, 2015 9:54 am

At long last, here is an ssd of The Antagonists.

I OCRd and corrected the listings, but Lurkio did all the hard work getting it to run, so credit to him.
Attachments
Antagonists.zip
(13.69 KiB) Downloaded 41 times

User avatar
lurkio
Posts: 973
Joined: Tue Apr 09, 2013 11:30 pm
Location: Doomawangara
Contact:

Re: Antagonists and The Secret of Arendarvon Castle

Postby lurkio » Sun Nov 29, 2015 10:17 pm

The Antagonists can now be played online. Click here to play online.

iamaran wrote:At long last, here is an ssd of The Antagonists. I OCRd and corrected the listings, but Lurkio did all the hard work getting it to run, so credit to him.

Thanks, Aran. What was odd about this game was that although the program listings used Arend Rensink's patented bytecode/checksum system (first seen in The Secret Of Arendarvon Castle), the authors of The Antagonists seemed to have cocked the system up.

The BASIC decoder programs were supposed to decode random-looking alphanumeric strings (from DATA lines) and store them in a chunk of free RAM, which the user would then manually save to disc. The saved file would contain machine code routines and data for the game.

However, some of the decoder programs were terminating with strange errors. I suspected that BASIC's stack was being corrupted, because PAGE was set very high. So I fiddled with Shadow RAM in Master 128 mode in BeebEm to try to get round the problem, but with limited success. Then I finally realised that instead of poking the decoded bytes into RAM, I just needed to write them straight to disc, using BPUT#, so I did. Problem solved.

So, it looks like the authors did encode all the game data correctly, but they left bugs in the decoder programs, which made the game impossible to decode (let alone play) without some tinkering.

Capture1.PNG
Screenshot
Capture2.PNG
Screenshot
01.jpg
Front cover of the book


Return to “archive requests”

Who is online

Users browsing this forum: No registered users and 1 guest