The Taroda Scheme (BBC version)

want to contribute an update to the archive? post it here!
Post Reply
User avatar
billcarr2005
Posts: 1191
Joined: Fri Sep 09, 2005 3:01 pm
Location: UK
Contact:

The Taroda Scheme (BBC version)

Post by billcarr2005 » Sat Feb 24, 2018 11:46 pm

The disk / code protection used is detailed here

viewtopic.php?f=2&t=9061&p=195316#p195316
Attachments
The Taroda Scheme.zip
The Taroda Scheme (BBC version)
(37.62 KiB) Downloaded 92 times

User avatar
lurkio
Posts: 1564
Joined: Tue Apr 09, 2013 11:30 pm
Location: Doomawangara
Contact:

Re: The Taroda Scheme (BBC version)

Post by lurkio » Sun Feb 25, 2018 12:40 am

Thanks, BillC!

Just a minor note: the .SSD won't work if you've got the PRES Advanced BASIC Editor ROMs installed because they intercept the command *B, which clashes with the name of a machine-code file on the .SSD which seems to be run with the same command, *B!

:!:

User avatar
CMcDougall
Posts: 6058
Joined: Wed Feb 02, 2005 3:13 pm
Location: Shadow in a Valley of Scotland
Contact:

Re: The Taroda Scheme (BBC version)

Post by CMcDougall » Sun Feb 25, 2018 8:30 am

Great job, glad you got the disc, & forced it to copy =D> =D> =D>
ImageImageImage

User avatar
billcarr2005
Posts: 1191
Joined: Fri Sep 09, 2005 3:01 pm
Location: UK
Contact:

Re: The Taroda Scheme (BBC version)

Post by billcarr2005 » Sun Feb 25, 2018 10:07 am

lurkio wrote:Thanks, BillC!

Just a minor note: the .SSD won't work if you've got the PRES Advanced BASIC Editor ROMs installed because they intercept the command *B, which clashes with the name of a machine-code file on the .SSD which seems to be run with the same command, *B!

:!:
I always find it's best practice to disable any unnecessary ROMs when loading up any software, for maximum compatibility.
You could also argue it's bad practice to just have *B rather than */B or *RUN B in the code, I assume they did this to make it harder to scan through the data and see the obvious and/or to save space.
However it's fairly trivial to change the filename and where it's OSCLI'd from by hex-editing the SSD - offset &18 (the catalogue) and &16EA6 (it's position in the file BOOT, &ACE when the file is *LOADed)

User avatar
lurkio
Posts: 1564
Joined: Tue Apr 09, 2013 11:30 pm
Location: Doomawangara
Contact:

Re: The Taroda Scheme (BBC version)

Post by lurkio » Sun Feb 25, 2018 10:35 am

billcarr2005 wrote:it's fairly trivial to change the filename and where it's OSCLI'd from by hex-editing the SSD - offset &18 (the catalogue)
That's the wrong catalogue entry! It's the one at offset &08 that you need to edit.
billcarr2005 wrote:and &16EA6 (it's position in the file BOOT, &ACE when the file is *LOADed)
Thanks.

Have you got any documentation/instructions for the game?

:?:

User avatar
billcarr2005
Posts: 1191
Joined: Fri Sep 09, 2005 3:01 pm
Location: UK
Contact:

Re: The Taroda Scheme (BBC version)

Post by billcarr2005 » Sun Feb 25, 2018 12:06 pm

lurkio wrote: Have you got any documentation/instructions for the game?

:?:
Attachments
The Taroda Scheme Instructions 1.jpg
Instructions Side 1
The Taroda Scheme Instructions 2.jpg
Instructions Side 2
Heyley Software Disc-Based Adventure Games.jpg
Advertisement

User avatar
lurkio
Posts: 1564
Joined: Tue Apr 09, 2013 11:30 pm
Location: Doomawangara
Contact:

Re: The Taroda Scheme (BBC version)

Post by lurkio » Sun Feb 25, 2018 7:23 pm

billcarr2005 wrote:[instructions]...
Thanks!

Btw, I assume the files O.B and O.Boot can be deleted? And an instructions program added? Does it matter which precise sectors the files occupy?

:?:

User avatar
billcarr2005
Posts: 1191
Joined: Fri Sep 09, 2005 3:01 pm
Location: UK
Contact:

Re: The Taroda Scheme (BBC version)

Post by billcarr2005 » Sun Feb 25, 2018 8:27 pm

lurkio wrote:
Btw, I assume the files O.B and O.Boot can be deleted? And an instructions program added? Does it matter which precise sectors the files occupy?

:?:
Yes, O.B and O.Boot are the original, unmodified versions of the files, they can safely be deleted.
I'm fairly certain that R/H1 can be removed too... this does contain code, but refers to the protection and the file originally was longer and further data occupied the "bad" tracks which couldn't be read under normal DFS conditions (and just contained E5 anyway)
There shouldn't be any direct access of the disk with OSWORD&7F, so files are able to be moved around too :)

User avatar
lurkio
Posts: 1564
Joined: Tue Apr 09, 2013 11:30 pm
Location: Doomawangara
Contact:

Re: The Taroda Scheme (BBC version)

Post by lurkio » Mon Feb 26, 2018 7:16 pm

billcarr2005 wrote:Yes, O.B and O.Boot are the original, unmodified versions of the files, they can safely be deleted.
I'm fairly certain that R/H1 can be removed too...
Done and done.

I've typed up the instructions, put them on an .SSD together with the game itself, and uploaded it to bbcmicro.co.uk:
:idea:

Post Reply