BBC games that don't run properly on a BBC B

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Michael Brown
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BBC games that don't run properly on a BBC B

Postby Michael Brown » Wed May 27, 2015 6:35 pm

Hi All,

2 titles that are for the BBC don't work on it.

They are

1) Airlift by Bug-Byte
2) Robo Swamp by Software for All.

Both games are from 1982.

Am I right in thinking these are for the OS 0.1?

The control keys do not response on Airlift - but it works fine under b-em with OS 0.1 selected.

A "no room at line..." error crops up on Robo Swamp on Beeb-Em (even if downloaded to &E00) and also the graphics are not right - but it works fine in Master Mode.

Can anyone help with sorting these 2 games out so they can be made to work on a normal BBC or under emulation in BBC B mode.

I know they are not the best games, but I would still like to have them working on a disc.

regards,
Mick.

PS another one with graphics corruption is The Three Crystals by Potter Programs. It is part of their Arcade 4 Pack and the other 3 games in it work fine.

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leenew
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Re: BBC games that don't run properly on a BBC B

Postby leenew » Wed May 27, 2015 8:42 pm

Hi Mick,
Are you saying the original tapes do not work correctly on the beeb? or just that none of the tape-to-disc hacks work properly?
Cheers,
Lee.

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Re: BBC games that don't run properly on a BBC B

Postby Michael Brown » Thu May 28, 2015 9:03 am

Hi Lee,

I only have the tape image for Airlift and it does not work properly.

I think someone needs to take a look at the VDU commands in Three Crystals and change them to work on a BBC B like what happened with Fruit Machine by A.Crump a short time back.

Airlift looks like is uses a "asc" command which may only be OS 0.1 based, so would need someone to change the way the keys are detected in order for it to work correctly.

As for Robo Swamp, the "no Room at line ..." seems to be the direct fault of a build up of data filling all the available space left in memory.

here is a disc with the original files on for each game.

FaultyOS01 games.zip
(15.13 KiB) Downloaded 43 times


regards,
Mick.

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Re: BBC games that don't run properly on a BBC B

Postby richardtoohey » Thu May 28, 2015 9:10 am

I'm looking at Airlift now.

It doesn't start-up probably on a BBC B 1.2 (under Beebem) but it does on a Master. On both it doesn't respond to key strokes.

On the Master it places the treasure and draws the meteors, on the BBC B it doesn't even get that far, but I think I've found the bug (EDIT or maybe not!)

I'm working off the UEF from here:

http://www.stairwaytohell.com/bbc/archi ... Byte_B.zip

@Mick where do you think the non-functional key-reading code is? I can't find any, but it must be there somewhere! The asc code I'm seeing is all about placing the characters and detecting what character (if any) is there.

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Re: BBC games that don't run properly on a BBC B

Postby richardtoohey » Thu May 28, 2015 9:44 am

The issue that stops it drawing the urns and meteors on OS 1.2:

Code: Select all

 1300X=RND(33)+4:Y=RND(24)+6:IF FNasc(X,Y)<>255 THEN 1300
It gets stuck in an endless loop there, because instead of getting character 255 it gets 159. Change that 255 to a 159, and it gets further. Also change

Code: Select all

  990CMP #255:BEQ knock
EDIT: so the characters defined are:

Urn 249, but *FX135 returns 153 on OS 1.2
Helicopter 250, we get 154,
Meteor 254, we get 158
Block 255, we get 159

So I guess (?) that on OS 0.1 and MOS 3.2, you get the defined character e.g. 255, but on OS 1.2 you get 159.

To make it work on OS 1.2, I'm planning on making URN%,BLK%,HEL% and MET% variables and using them in the code - that should fix it for OS 1.2.

For the keys not working, it's here:

Code: Select all

  180I%=INSTR(CK$,CHR$(?215))-1:IF I%<0 THEN PROCwait(5):GOTO 260
There's something in OS 0.1 at 215 (&D7) that it uses to decide whether or not to let you move. Under OS 1.2 or later, I% always ends up less than 0, so you never move. Fudge it like this

Code: Select all

  180I%=INSTR(CK$,CHR$(?215))-1:I%=1:IF I%<0 THEN PROCwait(5):GOTO 260
and the helicopter moves (not under your control.)

So if "we" can figure out what is stored at &D7 under OS 0.1, and where that is in OS 1.2 (and 2.0 and 3.2 and 3.5) then we can fix it. Or alternatively, tweak the code to do the same thing as the PEEK.

EDIT: :idea: :idea: :idea: Last key pressed! Change that 215 to &EC (in line 180), and the keys work! Thank you to http://mdfs.net/Docs/Comp/BBC/AllMem

The game still doesn't work because it isn't recognising the other game objects (because of the first issue), so still a bit more work to do ...

Attached is a Master-only version with that change to line 180, no other changes.

Note that you have to pick the urns up from above - so you have to wait until the meteors clear a space.
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AirliftM.zip
(3.83 KiB) Downloaded 36 times

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Re: BBC games that don't run properly on a BBC B

Postby richardtoohey » Thu May 28, 2015 10:19 am

Robo Swamp is also down to the characters.

Look at line 420 - VDU 31,X,Y, OSBYTE 135 to get the text character at the X,Y position. Then it looks for characters 225, 226 and 227.

Code: Select all

  420VDU31,D%,E%:A%=135:C%=USR(&FFF4)
  430C%=C%AND&FFFF:C%=C%DIV&100
  440IFC%=225ORC%=227THENENDPROC
  450IFC%=226THENSOUND0,-15,6,2:N%=N%+1:Q%=Q%-1:PRINTTAB(X%?I%,Y%?I%);" ":X%?I%=255:ENDPROC
On OS 1.2, you won't get those values - they'll be in the range 128 to 160. So same sort of fix as required for Airlift.

Don't know about No room message yet; one thing at a time!

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Re: BBC games that don't run properly on a BBC B

Postby richardtoohey » Fri May 29, 2015 9:45 am

Three Crystals is a bit simpler!

First file, T3C, change last two lines to:

Code: Select all

   11PAGE=&1B00
   12CHAIN"SCROLL"
Second file, SCROLL, change the last line to:

Code: Select all

  119CHAIN"3CRYSTA"
Final file, 3CRYSTA, need to delete some lines to make enough room for the character explosion. The deleted lines are purely to do with the REM control code protection.

So delete lines

Code: Select all

4,6,8
46,48
336,338
596,598
1000,1010,1020,1030,1040,1050,1060,1070,1080
Then it runs. I can't get off the first screen, so I don't know if there are any more out-of-memory issues lurking! :oops:

So the game needs two extra pages of RAM for the extra characters. I tried using OSBYTE 180 to fiddle with OSHWM but that seemed to work right up until *FX 20,1. So easier to start trimming down the program.

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Re: BBC games that don't run properly on a BBC B

Postby Michael Brown » Fri May 29, 2015 12:32 pm

thank you for taking the time to look at these.

Hopefully, in time, they can be amended to run on the Beeb!

Mick.

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Re: BBC games that don't run properly on a BBC B

Postby Michael Brown » Fri May 29, 2015 5:57 pm

Just taken another look at Three Crystals.

Using D|isc Doctor and *MZAP on the main game, I can see there are blank spaces of between 2 and 5 after a lot of the lines of data.
So far I have added a "A" to the end of the space just before the 0D so I can then list the program to see where the "A"s have been added then re-copy that line and hit return at the end of the data before the "A".
So far I have knocked &400 in space off the length of the program and still have a fair way to go, so hopefully the game will run at &1B00 without a "no room at line ..." message cropping up!

Thanks again for everything,
Mick.

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Re: BBC games that don't run properly on a BBC B

Postby richardtoohey » Fri May 29, 2015 8:09 pm

I almost got Airlift working but then it went wrong so I'm going back to square 1. It will need a download routine to get it to &E00, as well as the character code and PEEK address change.

Not sure what you are seeing with The 3 Crystals. With my change it works fine on BBC B mode (on Beebem) without any No room messages. Or do those occur if you get out the first room?

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Re: BBC games that don't run properly on a BBC B

Postby richardtoohey » Sat May 30, 2015 1:11 am

Here's an SSD with The Three Crystals working for me (I had to add in line 48 back in because there is a GOTO to it.)

Also Airlift. Changes as described above - so that ?215 becomes ?&EC; and the character detection uses the lowest possible value e.g. a block character (the green blocks in the middle) is returned as character 159 on OS 1.2, not 255. As well as the list above, we need to look for character 156 (252 in the original code) - this is the base (so without the change, you can never return the urn to the base.) So I've added AIRLFT1 to set PAGE and CHAINed AIRLFT2 to *LOAD the original BASIC AIRLIFT code and move it down to &E00. Works for me! :D

I think Robo-Swamp is much the same - in OS 0.1 you ask for the character at a text position, and you get the code you defined it as. On OS 1.2, you'll get the lowest possible value for it.

This is all on Beebem as BBC B with OS 1.2.
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FixedOS01games.zip
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Re: BBC games that don't run properly on a BBC B

Postby richardtoohey » Sat May 30, 2015 1:22 am

And same again, but Robo-Swamp fixed.

So it defines characters 224-228:

Code: Select all

   40VDU23,224,&3C,&3C,&18,&FF,&18,&3C,&66,&C3
   50VDU23,225,0,&3C,&7E,&5A,&7E,&66,&3C,0
   60VDU23,226,62,126,127,255,255,252,126,126
   70VDU23,227,0,24,60,126,126,24,24,60
   80VDU23,228,0,221,119,0,238,59,0,0
And then later on it is checking to see what characters are at a given position:

Code: Select all

  420VDU31,D%,E%:A%=135:C%=USR(&FFF4)
  430C%=C%AND&FFFF:C%=C%DIV&100
  440IFC%=225ORC%=227THENENDPROC
  450IFC%=226THENSOUND0,-15,6,2:N%=N%+1:Q%=Q%-1:PRINTTAB(X%?I%,Y%?I%);" ":X%?I%=255:ENDPROC
  470IFC%=224THENSOUND0,-15,2,2:PRINTTAB(D%,E%);CHR$225;TAB(X%?I%,Y%?I%);" ":R%=255:I%=B%:ENDPROC
But under OS 1.2, you will get the lowest character value - so you've written character 224 on-screen, but you will get character 128 back from OSBYTE 135. So for the above checks, we need to change:

224 to 128
225 to 129
226 to 130
227 to 131
228 to 132

It doesn't need any move-down code - seems to fit with PAGE at &1900 (quite an effective game considering the tiny size!)
Attachments
SecondFixedOS01games.zip
(15.17 KiB) Downloaded 61 times

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Re: BBC games that don't run properly on a BBC B

Postby Michael Brown » Sat May 30, 2015 3:40 pm

wow!

Thanks alot for sorting these.

The thing with The Three Crystals is that the main part originally loaded in at &1200 but now loads at &1B00 which means space of &900 is no longer available at the top of the program which may, only may, cause a "no room" message" at some point. So removing as much of any unncessary code as possible to lower the top of the program back down in memory should hopefully stop the "no room" message from appearing.

As for Robo-Swamp.
The seconf fix seems to be the same as the first and Robo Swamp still has the old values.
I can type them in, but if you have already done it then fine.

There was another thing I noticed with Robo Swamp and that was the the blue border on the game was printing double on the left hand side instead of single on both sides and is missing from the top. Is this another OS 0.1 thing?

regards,
Mick.

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Re: BBC games that don't run properly on a BBC B

Postby richardtoohey » Sat May 30, 2015 8:32 pm

Hhhmmm, sounds like I didn't upload the right version of Robo-Swamp, then. :?: But the only changes I made were those character codes, so if you give them a go it should also work for you.

Don't know about the blue border, I'll have to dust off a Windows machine and put b-em on there to have a look at how it works under OS 0.1.

The Three Crystals - yes, all makes sense to trim it down. I don't get any out of room messages, but then I haven't managed to finish a single screen of the three levels yet.

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Re: BBC games that don't run properly on a BBC B

Postby richardtoohey » Sun May 31, 2015 1:30 am

richardtoohey wrote:Don't know about the blue border, I'll have to dust off a Windows machine and put b-em on there to have a look at how it works under OS 0.1.
Ohh, just tried to build b-em 2.2 on OpenBSD, and I'm in business! :D I couldn't get 2.1 to build, but 2.2 plays nicely.

But I can't get DFS working under 0.1, so I can't load the SSD, so I can't open Robo-Swamp under 0.1. And I can't find a UEF anywhere - have you got one, Mick?

EDIT: Doesn't matter; if I run the game in Master mode it shows what it should look like, so I'll get it to do the same under OS 1.2.

EDIT2: It's down to (a) where characters get placed when VDU 5 is in operation, and I think also when you write the last character (at 20,31) - it automatically scrolls, so that's why you lose the top line.

Try this in OS 0.1, OS 1.2, and MOS 3.2 and you'll see the difference:

Code: Select all

VDU22,5,5,31,10,10,65
So it effectively does MODE 5, VDU 5, moves to 10,10 and writes an "A".

On OS 0.1 and 3.2, the "A" appears at position 10,10. Under OS 1.2, it will appear at the graphics cursor, and (probably just off-screen).

If you look at PROCstart, line 650, and the lines 680,690, and 700, they are drawing the border usings CHR$228 (with that CHR$4 in line 700 going back to writing text at the text cursor - VDU 4)

We can't just knock out the VDU 5, because without it the borders get drawn in green, and there are other potential side-effects.

So I think (?) the borders would have to be drawn with MOVE command equivalents.

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Re: BBC games that don't run properly on a BBC B

Postby Michael Brown » Sun May 31, 2015 12:29 pm

Hi Richard,

You are totally right about using the move statements.

I have now been able to amend Robo Swamp and make it look like it should by adding move 0,1020 to line 680, move 0,0 to line 690 and move 0,30 to line 700.

Also aded to line 690 to draw down the right hand side is a repeat:I=990:move1220,I:P.chr$132:I=I-32:untilI<50

roboswampfixed.zip
(1.68 KiB) Downloaded 36 times


thanks again for all your help in resolving the issues with these games.

I may have a few more games to post for resolving soon!!!

Mick.

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Re: BBC games that don't run properly on a BBC B

Postby CMcDougall » Sun May 31, 2015 2:54 pm

richardtoohey wrote:so I can't open Robo-Swamp under 0.1. And I can't find a UEF anywhere - have you got one, Mick?

no he doesn't nor will anyone, only went to disc on a real beeb and that was it :?
http://www.stardot.org.uk/forums/viewto ... 700#p79089
the other day I tried to load it again on more of my beeb's and it won't even show up on those :shock: so maybe why MIA, as it only seems to like the Issue3 beeb I got it with (clicks while loading in every block, with a few 'rewind tape's aswell) :o

nice work Richard 8) =D> =D> =D>
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Re: BBC games that don't run properly on a BBC B

Postby richardtoohey » Sun May 31, 2015 10:00 pm

Michael Brown wrote:I have now been able to amend Robo Swamp and make it look like it should
=D> I had a go myself but got bogged down very quickly. (Oops, that was an accidental pun!)
Michael Brown wrote:I may have a few more games to post for resolving soon!!!
Bring them on, it is interesting/fun to find out why they don't work. :D Can't guarantee success, but at least with these mostly-BASIC ones we've got a chance.

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Re: BBC games that don't run properly on a BBC B

Postby Michael Brown » Mon Jun 01, 2015 6:27 pm

Here is The Three Crystals with &300 in unused space removed cutting the main game down from &3C36 in length to &3936.

I have also added a pause routine to the first 2 files so you have chance to view them and also switched the cursor off.

thanks again for all your help soring out the vdu's

ThreeCrystalsfixed.zip
(10.06 KiB) Downloaded 40 times


PS Just needs play testing now to make sure no "no room at line..." errors pop up!

regards,
Mick.

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Re: BBC games that don't run properly on a BBC B

Postby richardtoohey » Mon Jun 01, 2015 8:24 pm

Michael Brown wrote:PS Just needs play testing now to make sure no "no room at line..." errors pop up!
Don't look at me, I couldn't get off any of the screens! :oops: Can't figure out how to get out of the room - I can't jump the beastie at the bottom; always run out of time on the snakes/crocs level; and have almost - but not quite! - got across the screen in the boat race.

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Re: BBC games that don't run properly on a BBC B

Postby CMcDougall » Mon Jun 01, 2015 8:24 pm

Michael Brown wrote:needs play testing now to make sure no "no room at line..." errors pop up!.

just done Key1 TheScroll (part1), using savestates so don't have to listen to the tune every death :cry: , but got through 3 rooms with no errs 8) , but don't think I will hurry to play anymore.....

Airlift, both versions don't work on the discs 'FixedOS01' & 'SecondOS1' , both say "
No such FN/PROC at line 100", I take it these still only work on M128? I have seen the screen after that err before, but got 42+ discs it 'might' be on :roll: :-k :-s
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Re: BBC games that don't run properly on a BBC B

Postby leenew » Mon Jun 01, 2015 11:52 pm

Michael Brown wrote:Hi All,

2 titles that are for the BBC don't work on it.

They are

1) Airlift by Bug-Byte
2) Robo Swamp by Software for All.

PS another one with graphics corruption is The Three Crystals by Potter Programs. It is part of their Arcade 4 Pack and the other 3 games in it work fine.


Mick, The Potter Arcade pack is on the MIA list, what 4 games are on it? Where are they archived?
Cheers
Lee.

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Re: BBC games that don't run properly on a BBC B

Postby richardtoohey » Tue Jun 02, 2015 2:14 am

CMcDougall wrote:Airlift, both versions don't work on the discs 'FixedOS01' & 'SecondOS1' , both say "
No such FN/PROC at line 100"
Hi, Col.

Are you CHAINing the new AIRLFT1 first? I've been getting them to work on BBC B (emulated) - probably won't work on a Master, no.

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Re: BBC games that don't run properly on a BBC B

Postby Michael Brown » Tue Jun 02, 2015 11:05 am

Hi Lee,

The Potter 4 pack were posted on the forum some time back.
I managed to get 3 of them to work.
I did post the working versions some time back.
They are Fruity, Hunchbach and Yartsie.

Now we have The Three Crystals as well!

Mick.

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Re: BBC games that don't run properly on a BBC B

Postby Michael Brown » Tue Jun 02, 2015 11:12 am

Another OS 0.1 game that has been the cause of concern is Martians from Micro Power.

Here is a disc tranfer of the OS0.1 version

MartiansOS0.1.zip
(3.69 KiB) Downloaded 37 times


All the aliens fall in the same spot.
However, if after downloading or loading the main game at &E00, you change the code at &208C and &2095 from &FE48 to &FE41 then the aliens will drop in slightly random places, but not as good as if the game is played in b-em with OS0.1 selected.
An amended version using this change is what is currently on Disc 069, but it would be great if someone could figure out what is happening and sort it properly.

regards,
Mick.

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Re: BBC games that don't run properly on a BBC B

Postby Michael Brown » Tue Jun 02, 2015 11:28 am

Hi Richard,

What happened to Galactic Intruder by Cosma.
I believe this also has OS0.1 issues.

Has anything more been resolved with it?

The last I knew was that you could load the tape image at &BF0 and then PAGE=&E00:OLD:RUN.

Mick.

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Re: BBC games that don't run properly on a BBC B

Postby CMcDougall » Tue Jun 02, 2015 7:18 pm

lee wrote:The Potter Arcade pack is on the MIA list, what 4 games are on it? Where are they archived?

yip, half onto .UEF full .SSD :P
viewtopic.php?f=7&t=8891&p=99215&hilit=the+potter+4+pack#p98857
richard wrote:Are you CHAINing the new AIRLFT1 first? I've been getting them to work on BBC B (emulated) - probably won't work on a Master

yip, doing that, on Laptop Win8.1 BeebEm414 Acorn1770 DFS2.26
but does not say Err on M128 in BeebEm414 , so that's when the next screen rang a bell on one of my discs
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Re: BBC games that don't run properly on a BBC B

Postby richardtoohey » Wed Jun 03, 2015 1:00 am

@Mick - those other games I think I just said "oh, they must be OS 0.1 only" - don't think there was any discussion of updating them to work on OS 1.2. I'll start having a look.

@Col - tried on b-em, too, AIRLFT1 and all good. So I'll try other DFSs and a real machine etc.

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Re: BBC games that don't run properly on a BBC B

Postby richardtoohey » Sun Jun 14, 2015 5:02 am

Michael Brown wrote:Another OS 0.1 game that has been the cause of concern is Martians from Micro Power.

Here is a disc tranfer of the OS0.1 version

MartiansOS0.1.zip


All the aliens fall in the same spot.
However, if after downloading or loading the main game at &E00, you change the code at &208C and &2095 from &FE48 to &FE41 then the aliens will drop in slightly random places, but not as good as if the game is played in b-em with OS0.1 selected.
An amended version using this change is what is currently on Disc 069, but it would be great if someone could figure out what is happening and sort it properly.

regards,
Mick.
Is this any better? (I can't see how to load a SSD on my b-em, it's tape-only, so can't test with OS 0.1)

Code: Select all

*LOAD MARTIAN
?&308D=&44
?&3096=&44
CALL &3200
It's using T1C-L instead of T2C-L.

I think/wildly guess that under OS 0.1 Timer 2 is in the right timing mode for the game to just work. Under OS 1.2 you'd have to set the mode correctly, but I don't know enough about the 6522s to work that out yet.

FE44 is already used for something in the game, so it might not work 100% properly if also using it for the "randomness" of the alien positioning - but maybe it will?

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Re: BBC games that don't run properly on a BBC B

Postby Michael Brown » Sun Jun 14, 2015 8:29 am

WOW!!!

Hi Richard, that poke &FE44 is much much better. In fact it seems to solve the issue.
However, you are right about ?&FE44 being used elsewhere, as it is used just before the new code at &3085 (before downloading) where there is a LDA &FE44 CMP &86.
Getting me thinking, I tried changing the poke from &FE48 to &FE45 instead and it seems to do the same thing as ?&FE44. I have checked through the machine code and found that there is no other ?&FE45s used.

Now testing the game under both BeebEm and B-em to see if any faults crop up.

BTW, does anyone know what the difference is between poking to &FE48, &FE44 and &FE45?

regards,
Mick.


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