Disc Doctor interference

[Michael Brown]

Hi All,

Yes Bill code works perfectly.
Just one last question. Would it work on a BBC with a Datacentre where Disc Doctor may be stored differently?

Mick.

[billcarr2005]

Just one last question. Would it work on a BBC with a Datacentre where Disc Doctor may be stored differently?

Since the code is only disabling the ROM with the matching header "DISC DOC" from within the paged ROM table I can't see why it shouldn't.
And stored differently how? If the name is different then the program can be altered to match the correct characters you'd expect to find.

[Michael Brown]

Hi Bill,

Just asking that was all. Sadly my BBC has been out of action for a couple of years so I cannot test the Datacentre myself.
It would have been nice to add this code to loaders of games affected by Disc Doctor but it has to be universal, well emulator and a real BBC and a BBC with Datacentre.

thanks for your help.
Mick.

[Michael Brown]

Added Bill's code to Atic Atac and sent it to Lee.
Hopefully it will work with a Datacentre,

If so, then I may be able to add the code to a couple of other games.

thanks again.
Mick.

[Michael Brown]

Another one to possibly take off the list is Jet Boot Jack as this is my fault. I had to move the original loading routine from &7F00 to somewhere else and chose &100 causing the Disc Doctor issue. The original tape has no issues.
I have corrected this problem and sent a copy to Lee to check.
If OK, then I'll repost D009.

regards,
Mick.

[Michael Brown]

Disc 053 now has the original Cyborg Warriors without the Disc Doctor check as that did not work correctly depending on your setup.

A message is now included on that page telling you that Disc Doctor causes text corruption.

regards,
Mick.

[Michael Brown]

Please not that Discs 009 and 010 have now been re-posted on the forum as Lee has confirmed they work on a real BBC with a Datacentre fitted,

regards,
Mick.

[vanekp]

Yes I have noticed that in the past that Disc Doctor causes issues with games I stopped using it or only loaded it into a ram bank when I needed to use it.
so I don't get what all the fuss is about.

[billcarr2005]

Disc 053 now has the original Cyborg Warriors without the Disc Doctor check as that did not work correctly depending on your setup.

Depending on the ROM header within the installed ROM...

Since you've been rather vague about the corruption on Cyborg Warriors, as well as the version of Disc Doctor which was installed, I installed Disc Doctor 1.10 on BeebEM 4.14 and checked myself.
Seems that "OPTIONS" is uncentred and split in half when Disc Doctor is installed?
The solution is... use the program I posted above, but change the string to "Disc Doc", since the program doesn't do any case normalisation (since ANDing the ROM header string with &DF would lose the space character), it just compares the exact string.
This "fixes" the error when I've briefly loaded it up, anyway...

Or alternatively, try this new version which turns "Disc Doc" into "DISC[00]DOC" and then checks against the stored value, so works with both variants
This doesn't explain why Atic Atac seemed to work, by presumably disabling the ROM, whereas it didn't disable with Cyborg Warriors?

edited to delete the superfluous DDOFF program

[billcarr2005]

Testing in BeebEM 4.14, with the following different versions of Disc Doctor

Code: Select all

CORRUPTED TITLE
DISC DOCTOR 1.05
DISC DOCTOR 1.07
DISC DOCTOR 1.09
Disc Doctor 1.10
DISC DOCTOR R

OK
DISC DOCTOR 1.0A
DISC DOCTOR 1.0B

*DDOFF disables all of the above and Cyborg Warriors doesn't have the bad OPTIONS. Maybe there's a conflict with the Datacentre?

[Pernod]

Code: Select all

CORRUPTED TITLE
Disc Doctor 1.10
DISC DOCTOR R

I don't believe these are official releases and are probably best ignored.

[Michael Brown]

Sorry about the vagueness.

DISC DOCTOR 1.09 is what I used.

Also, It was my code that Cyborg Warriors did not detect, that was the checking &130 for &0D or anything other than 0 that I removed. Not the ROMOFF code that works for Atic Atac.

The issue I have is this.
All my games worked fine on my old real BBC B BITD with no sideways ROM or extra ROMS fitted.
They also work fine under BeebEm and Bem as they have been tested by Lee and others.
The possible problem may be when someone transfers a copy of these games onto a USB stick and then loads them into a real BBC that has a Datacentre fitted as this may come with Disc Doctor and other ROMs and therefore interfer with the game as mentioned in the list I posted here.

I have now added comments with each disc on the forum highlighting the disc doctor clash.
Hopefully, I will be able to sort each of these games in turn over the next few months.

It is only a few games and some of them were only affected by amending them to work from disc in the first place as the original tapes were fine.

Mick.

[billcarr2005]

DISC DOCTOR 1.09 is what I used.

Also, It was my code that Cyborg Warriors did not detect, that was the checking &130 for &0D or anything other than 0 that I removed. Not the ROMOFF code that works for Atic Atac.

I see. So the 2nd, uppercase ROM header checker is probably redundant! I would've thought you'd use the method which was *thought* to work, rather than devise a method which didn't

The issue I have is this.
All my games worked fine on my old real BBC B BITD with no sideways ROM or extra ROMS fitted.
They also work fine under BeebEm and Bem as they have been tested by Lee and others.

As they would, because they are "vanilla" BBCs where nothing would interfere. All the code was written to not rely on any additional code (such as *MRUN to relocate tape files when running from disk). Problems will possibly arise when code is moved around from it's initial place and / or when additional ROMs are installed, but the route out of the problem isn't to change things some more.

The possible problem may be when someone transfers a copy of these games onto a USB stick and then loads them into a real BBC that has a Datacentre fitted as this may come with Disc Doctor and other ROMs and therefore interfer with the game as mentioned in the list I posted here.

Surely that's when a workable system like disabling the ROM would solve the problem, which was given to you on a silver platter, then led to believe that it didn't work on some systems, presumably without being tested?

[Michael Brown]

Hi Bill,

The program you gave me is now being installed into the games that need it.
So far Atic Atac has had it installed and Lee has confirmed it works.
I have also put it into Spellbinder and given a copy to Lee to check when he gets time.
Also some of the games were my doing like Jet Boot Jack that didn't need the ROM code, but just needed the loader moving elsewhere as the original tape version worked fine.

Also another one to remove from the list is Qwak.
Again the tape works fine.
It was me shifting its loader from &7000 to &100 to avoid screen distortion that caused the issue.
I have now amended this and the code is at &7A00 and I have sent Lee the new copy to check.

Again, thanks for the program and I will use it where I can.

regards,
Mick.

[Michael Brown]

Hi All,
Now been able to add Bill's ROM fix to Cyborg Warriors.
Stored in my CYBLOAD file at &22A0 and is called just before loading the code at &100.
I have sent a copy to Lee to try and if all is OK, then I will repost the disc.

Thats all for now.

Thanks again to everyone who has helped me sort this.

regards,
Mick.

EDIT: Also managed to add Bill's code to Thunderstruck II and White Light and they work OK for me.
I will send Lee the discs tomorrow.
That really is it for today now.
Mick.

[Michael Brown]

Another one to cross off my list is By Fair Means Or Foul.
This is the same game as Pro Boxing and the tape version of that loads with Disc Doctor.
The Disc Version of BFMOF loads the game at &400 and not &100 like mine.
Changing my code to run from &400 cures the problem.
Different problems occurred depending on what variable was strored at &130. Some made it skip the loader and some made the game crash at that loader. Now it seems to work.
I will send Lee the disc tomorrow for him to check.

regards,
Mick.

[Michael Brown]

BTW adding Bill's code to Omega Orb also cures that graphic glitch.
Again, I will send the disc to Lee tomorrow.

And that really is it now as the wife is back!

Mick.

[billcarr2005]

Another one to cross off my list is By Fair Means Or Foul.
This is the same game as Pro Boxing and the tape version of that loads with Disc Doctor.
The Disc Version of BFMOF loads the game at &400 and not &100 like mine.
Changing my code to run from &400 cures the problem.

Then why not just use the disc version?
So many changes... causing trouble down the line

[Michael Brown]

Hi Bill,
IIRC the reason why I did not to use the BFMOF disc version was because BITD the tape version was protected but a disc hack of it was given to me and that is what was used. When I came to remaster the games a few years back, I found a disc version on STH but it had extra files that loaded a master version or SWR version or something. But I did not have the disc space to store these extra files, so I kept the game in the form it was, but I did not realise that disc doctor was a problem at the time.
Hopefully now it is correct.

Mick.

[Michael Brown]

Hi All,
Qwak and By Fair Means or Foul have now been checked by Lee are OK.
I have re-posted Discs 042 and 044.

Also D053 with Bill's fix for Cyborg Warriors has been re-posted too.

More to follow once confirmed OK.

Mick.

[billcarr2005]

IIRC the reason why I did not to use the BFMOF disc version was because BITD the tape version was protected but a disc hack of it was given to me and that is what was used. When I came to remaster the games a few years back, I found a disc version on STH but it had extra files that loaded a master version or SWR version or something. But I did not have the disc space to store these extra files, so I kept the game in the form it was

I've just checked bbcmicro.co.uk and discovered that the much enhanced 128K version isn't uploaded there - it's got selectable fighters and music!
Also, I didn't check if A, B and C are exactly the same as 2,3 and 4 despite having the same attributes and the default, unexpanded version always loads 0,1,2,3,4 which are all on the same side, whereas 6,7,8,9,A,B,C are on the other.
Whilst disassembling the game, both on the original disk (protected) and PIAS (unprotected) versions, I bodged a slightly different / more compact loader which removed the checks used in the 128K version and borrows the reused OSCLI command to load the files.

*/BFMOF to load

edit: a quick *LOAD of 2 & A, 3 & B and 4 & C into screen memory show that all of the files are different
further edit: although somewhat confusingly, FOULA, FOULB and FOULC don't contain the contents of the PIAS re-release files A,B and C or the 11,12 or 13 file loaded from the original disk... rather they contain the contents of 2, 3 and 4. Obviously they could be called red, green and blue... but such gratuitous changes seem

[Michael Brown]

Hi All,
D035 and 037 with Spellbinder and Omega Orb now re-posted with Bill's Fix.

That just leaves Thunderstruk II on D034.
Bill's fix has been added and it works fine except...
Lee has reported that on a real BBC with Datacentre, there is some fast flicker on the robot on the second screen ( I believe it is the robot's eye that flashes red and yellow).
Indeed I had not noticed as my test setup had Disc Doctor in slot 13 (which poked &0D to &130).
Loading it into slot 0 (to emulate a Datacentre) shows this glitch.
It is there on the uef tape when slot 0 is used, but not if any other slot is used as far as I can tell.
Therefore it is not a fault of my transfer and must be something else.

Anyone got any ideas?
Could a simple *FX command sort this out?

I have attached a copy of the current build of D034.
This has not been uploaded to the forum as I would like to see if this glitch can be patched so the game can work on a real BBC with a Datacentre fitted.

regards,
Mick.

Disc034.zip

(215.7 KiB) Downloaded 79 times

[billcarr2005]

Lee has reported that on a real BBC with Datacentre, there is some fast flicker on the robot on the second screen ( I believe it is the robot's eye that flashes red and yellow).
Indeed I had not noticed as my test setup had Disc Doctor in slot 13 (which poked &0D to &130).
Loading it into slot 0 (to emulate a Datacentre) shows this glitch.
It is there on the uef tape when slot 0 is used, but not if any other slot is used as far as I can tell.
Therefore it is not a fault of my transfer and must be something else.

Anyone got any ideas?
Could a simple *FX command sort this out?

This happens under emulation on BeebEM 4.14 and bEM 2.2 - without any Disc Doctor ROM and / or without any hint of Datacentre nearby... I believe it's designed that way! Most of the sprites have some form of animation...
I think it's the red pixel to the left. I would hazard a guess that the two large dots to the right are the eyes and the antennas at the top are the ears.

ThunderstruckII.png (414 Bytes) Viewed 7997 times

[Michael Brown]

Thanks for that Bill.

BTW I have found another one.
Chicane has some code that loads the game at &100.
It worked fine for me as it actually stored &0D at &130 which is why I missed it, It was only when I loaded Disc Doctor at slot 0 that it crashed as it stored &0 at &130.
I have amended the code to load from &140 instead and sent it to Lee to check.
There is no uef tape copy of this at STH to check to see if this was caused by the disc hack or not.

[billcarr2005]

There is no uef tape copy of this at STH to check to see if this was caused by the disc hack or not.

I'd hazard a guess that the answer to this conundrum is a resounding yes!

[Michael Brown]

Chicane on D013 has now been reposted.

Another strange one is Network (another Peter Scott game).
This one works fine on my BeebEm setup with Disc Doctor in slot 13 (0D) which again is why I missed it first time around.
Lee has confirmed that on his real BBC with A Datacentre with Disc Doctor ?&130 returns a value of 11.

Loading Disc Doctor under BeebEm into slot 11 causes the game to loose its screen data and you just fall and fall and then a "bad program" appears.

Running Bill's ROM fix cures this, but first I have asked Lee to try the game on his setup first just to see what happens on real hardware.
If Lee reports a fault then I will amend the game accordingly.

Mick.

[leenew]

I have only confirmed that, at the minute, it returns 11, as that is where it is, at the minute...

Lee

[Rich Talbot-Watkins]

Just to say, I don't think Bill's program can have any negative consequences whatsoever, as it just disables a ROM with a specific name, and there won't be any game ever which relied on the presence of a ROM (let alone one called "DISC DOCTOR"!) to operate correctly.

I'd be inclined just to run that code from the menu program itself to save having to patch individual disk images.

[Michael Brown]

Hi All,

I think that is all the games now anyway.
I think if there were more, then I would have added Bill's code to the !BOOT file on my disks.

I now only need to ad the code to Network, Kastle and Thai Boxing and that is it.

Now I know what to look out for I should be able to add this code to any new stuff that comes my way.

Thanks again.

Mick.

[Michael Brown]

Discs 108 and 110 have now been reposted and that concludes this fix for my discs.

If any minor errors are found in future then a message will be added to that disc's post.
One has just been added to D027 to warn of possible interference with Network

regards,
Mick.