*KEY interference in games

having trouble with an archived file or want to correct something? report it here!
Michael Brown
Posts: 1896
Joined: Sat Apr 03, 2010 12:54 pm
Location: Nottingham

*KEY interference in games

Postby Michael Brown » Thu Jan 05, 2017 3:03 pm

Hi all,

Played a few games over xmas - the first time for a long time and noticed something odd.

Found that pressing f0-f9 by mistake during some games or in the high score resulted in the following...

1) Loud bleep in high score table.
2) Complete mess displayed in high score table.
3) Broke the game in high score table.
4) Games went wild when asked to enter details such as Y/N or entering co-ordinates etc.

Upon exploring various games, I discovered that some authors had obviously come across this problem and used a fix which is...
1) *FX225 in the basic code
2) LDA#&E1 LDX#&00 JSR&FFF4 in machine code.

The reason for this error is when code gets loaded at (or downloaded over) &B00 that does not contain 101010101010 etc.

I am currently working through my games and will re-post any games that contain this error.
Each game needs testing and this may take some time.

Obviously, any game that uses *KEY commands in basic cannot be cured with the above.
Using *FX18 afterwards is a no-no as this puts the 1010101010 back at &B00 and so wipes any code that is stored there breaking any game that relies on it.

The quickest and simplest fixes are adding *FX225 in the loader or adding the M/C routine to the game after the downloading routine just before calling the execution address.

I have already e-mailed Lee about this.
Just wondering if anyone else has come across it.

Some of the games include...
Chuckie Egg, Fortress, Copter Capers, Repton and Boffin.

BITW
Happy new year

Mick.

User avatar
tricky
Posts: 1918
Joined: Tue Jun 21, 2011 8:25 am
Contact:

Re: *KEY interference in games

Postby tricky » Thu Jan 05, 2017 5:41 pm

I remember a few BITD that fail if you press escape too.
I certainly would be nice to fix, but you can't fix'em all (BREAK).

Michael Brown
Posts: 1896
Joined: Sat Apr 03, 2010 12:54 pm
Location: Nottingham

Re: *KEY interference in games

Postby Michael Brown » Fri Jan 06, 2017 8:08 am

Yes I remember too that if you pressed ESCAPE rapidly and continually then you coud break into some games where basic code had the ON ERROR RUN statement not at the start of the code but a *FX200,0 or *FX200,2 was.
I believe that I corrected these as I found them.

If anyone knows of any game you can break into like this, then please let me know.

As for the *KEY problem... I am going to have a go at fixing ALL of them!.

regards,
Mick.

Michael Brown
Posts: 1896
Joined: Sat Apr 03, 2010 12:54 pm
Location: Nottingham

Re: *KEY interference in games

Postby Michael Brown » Fri Jan 13, 2017 3:29 pm

Now started to re-post my 30th Anniversary collection in blocks of 10 discs at a time in the Submissions thread,

Hopefully, this will sort the issue for anyone who wants better versions of the games.

regards,
Mick.

Michael Brown
Posts: 1896
Joined: Sat Apr 03, 2010 12:54 pm
Location: Nottingham

Re: *KEY interference in games

Postby Michael Brown » Sat Jan 21, 2017 3:19 pm

Just re-posted the next batch of 10 discs with amended *KEY versions.

Discs 021-030 will be posted next week!

regards,
Mick.

PS Also found that some games have a *KEY 0 DELETE 30,50]MOLD]MRUN]M
which also left KEY 0 putting this code into high scores when pressed.
Again *FX225 command added after the procedure was implemented caused no further problems.
BTW putting a *FX225 beforehand cause the *KEY command to be ignored and therefore the game will not work, so all fixes must come afterwards.
Some of the G J Key games in The Micro User like Dino also use *KEY functions that need the *FX225 adding afterwards.

Hopefully, the fixes will make better gameplay!

Michael Brown
Posts: 1896
Joined: Sat Apr 03, 2010 12:54 pm
Location: Nottingham

Re: *KEY interference in games

Postby Michael Brown » Fri Jan 27, 2017 1:23 pm

Looking through even more games I have also noticed that some of the *KEY issues have been caused by the downloading process.
Either by having the *KEY0 OLD RUN routine included or by loading parts of the game between &0900 and &0D00 and then moving them up to &E00 which leaves the code at &B00 which causes the problem.

Under these conditions. it is not the fault of the author, but just one of those things caused as a result of trying to get the games to run off disc. At least now, they should all work correctly.

BTW, Discs 021-030 have now been re-posted in the Submissions thread.

Michael Brown
Posts: 1896
Joined: Sat Apr 03, 2010 12:54 pm
Location: Nottingham

Re: *KEY interference in games

Postby Michael Brown » Fri Feb 03, 2017 11:30 am

Discs 031-040 have now been re-posted over in the submission thread.

regards,
Mick.

Michael Brown
Posts: 1896
Joined: Sat Apr 03, 2010 12:54 pm
Location: Nottingham

Re: *KEY interference in games

Postby Michael Brown » Fri Feb 10, 2017 1:19 pm

Discs 041-050 have now been re-posted over in the submission thread.
Halfway there now!

regards,
Mick.

Michael Brown
Posts: 1896
Joined: Sat Apr 03, 2010 12:54 pm
Location: Nottingham

Re: *KEY interference in games

Postby Michael Brown » Fri Feb 17, 2017 5:29 pm

Discs 051-060 have now been re-posted over in the submission thread.
Getting there now!

regards,
Mick.

Michael Brown
Posts: 1896
Joined: Sat Apr 03, 2010 12:54 pm
Location: Nottingham

Re: *KEY interference in games

Postby Michael Brown » Tue Feb 21, 2017 9:48 am

I have now been able to sort out just about all the games in my collection (except for games that feature the use of *KEY functions in their gameplay which have been left as they are).

There is just a few games I have not been able to sort - these are the likes of Questprobe One and Hex (both text adventures).
Something in their code affects the function keys - nothing bad, but *FX225 doesn't sort it like the rest.
Can anyone help?

regards,
Mick.

Michael Brown
Posts: 1896
Joined: Sat Apr 03, 2010 12:54 pm
Location: Nottingham

Re: *KEY interference in games

Postby Michael Brown » Wed Feb 22, 2017 1:05 pm

Upon further inspection of the games that *KEY command interfere with that *FX225 won't resolve - I have noticed that they are all one file starting at &2900 around &3500 in length. It looks like they are all the same engine so if a fix can be found for one game, it may be possible that it may fix them all.
It looks like it is the QUILL program.

Anyone help?

It would be great to sort these before I re-post discs 091-100.

regards,
Mick.

Michael Brown
Posts: 1896
Joined: Sat Apr 03, 2010 12:54 pm
Location: Nottingham

Re: *KEY interference in games

Postby Michael Brown » Fri Mar 03, 2017 12:20 pm

All discs up to and including Disc 080 have now been re-posted.

Sadly not been able to sort *KEY problems with Quill based text adventures.

Mick.

Michael Brown
Posts: 1896
Joined: Sat Apr 03, 2010 12:54 pm
Location: Nottingham

Re: *KEY interference in games

Postby Michael Brown » Tue Mar 07, 2017 3:54 pm

Just about all games on all discs now sorted.

Sorted all the Quill ones - simply changing the &A5 at &298E to &00 as the Quill program was basically doing a *FX225,165 and now does a *FX225,0 instead.

Should have spotted this earlier - but better late than never.

Just leaves Questprobe One and Mystery Fun House - both by Mak Jukic
QP1 has a LDA#&91 command at &3658 which allows you to press the function keys and get different colours.
I have not yet been able to find a way around this issue.
If anyone can help?

regards,
Mick.

Michael Brown
Posts: 1896
Joined: Sat Apr 03, 2010 12:54 pm
Location: Nottingham

Re: *KEY interference in games

Postby Michael Brown » Fri Mar 10, 2017 1:07 pm

Just re-posted discs 081-090 in the other thread.

Next week will be discs 091-100 (the text adventure games).
All of these are fixed except the 2 Mak Jukic games - although pressing the function keys only changes the text colour and doesn't crash the games, so I may just leave them as they are if a fix cannot be found in time.

regards,
Mick.


Return to “archive issues”

Who is online

Users browsing this forum: No registered users and 3 guests