Clues over Clues on ATARI XL

[emkay]

In 1990 I finished a Game named ADMIRANDUS. Because there is no EMULATOR that shows the game correct, I made a screenshot with my Pc-Capture Card. It IS from my 800XL, but what is going to be wrong on the screen ?

[TXG/MNX]

Nice graphics especialy the small picture. What do you have to do in the game?

 

TXG/MNX

[Sheddy]

Yep, very nice

 

Here's my guess..

 

I'd say that top 1/3 although it looks complex is mostly just PM overlays and DLIS, and will display OK

 

But I guess the bottom 1/3 is going to look wrong coz the emulators don't do horizonal timing right yet. Either you're switching from gr.8 (or 0) to gr.15 horizontally or you're multiplexing the PM's horizontally.

 

[DEBRO]

But I guess the bottom 1/3 is going to look wrong coz the emulators don't do horizonal timing right yet. Either you're switching from gr.8 (or 0) to gr.15 horizontally or you're multiplexing the PM's horizontally.

 

 

I'd be interested to know too.

 

I tried a trick like that but couldn't get it to work on the emulator. I never tried it on the real 8-bit. I was told that 2 graphic modes on one scan line might be impossible because ANTIC reads the display list for the scan line and doesn't re-read it for the graphic mode update. I wanted to try it though versus taking what was written

[Heaven/TQA]

try the following...

 

use ANTIC F (gr.... 1/3 of scanline do not change anything, then switch the PRIOR register ($40) and go into mode9 after another 1/3 switch back to antic f ($00) and antic should produce something similar to antic e...

 

this was told me (i never tried it...) by coders. you can see this effect in HARD demos like "Joyride".

 

my 2 cents regarding atari "hardware" bugs...

 

hve

[Jetboot Jack]

Debro,

 

You're right you cannot change graphics mode mid scanline - I've never seen it done...

 

But as Hve says you can flip the GTIA mode bits midline to switch between Antic F and and any GTIA (9, 10 and 11 in basic modes) effects - since they are the same graphic mode as far as Antic knows

 

You could also do the same trick with GRIOR and Antic 2 to flip between normal text and wierd GTIA mode text (Murder on the Zinderneuf by EA was done in these modes)...

 

sTeVE

[emkay]

High HVE!

 

 

 

>use ANTIC F (gr.... 1/3 of scanline do not change anything, then switch the PRIOR register ($40) and go into mode9 after another 1/3 switch back to antic f ($00) and antic should produce something similar to antic e...

 

Yes, You are right.

 

 

 

>this was told me (i never tried it...) by coders. you can see this effect in HARD demos like "Joyride".

 

But, I did it before

 

>my 2 cents regarding atari "hardware" bugs...

 

If it is for real a bug or not, that would be unkown. But, did you ever seen it on a GAME?

 

Hard-Software did great things, but did they great things for the ATARI?

 

I wanted to do great things for that great machine!

 

For those who want to know: The Game is a type of "Wheel of fortune".

 

 

 

But, there is more...look at it.

[emkay]

BTW:

What you can't see, is the Sound of the Game that is using a 2-point modulation, that is far beyond a SID on C64 and uses only a VBI-routine.

 

Believe it or not

[Sheddy]

Not sure what you mean by 2 point modulation, but I think I'm not the only one who would like to see this game!

How about posting a .bin of it?

[emkay]

@Sheddy

 

 

May I send it as an ATR in an E-Mail?

 

Remember an ATARI-Emulator doesn't show the correct graphics and the sound is not correct played too...

 

Hmmm.... maybe on a 60Hz ATARI, the graphics might be wrong too, and due to the VBI, the sound may be faster.

[Sheddy]

[email protected]

 

thanks

[emkay]

So if you put that game on an original machine and while in the game, just wait a few minutes for the pause-mode

 

[emkay]

Does anyone know, how many Steps of the 6502 are made in one Scanline? At 50Hz and at 60Hz?

So think about it, when using WSYNC with only a change of a Color...

Till the end of the Scanline, the whole Computer does nothing!

So don't be surprised, getting crackles in Digi-Sounds...

So, make a Routine, that playes the Digi-Sound, while using/in a DLI and forget WSYNC