Creativision and CVBasic with mame

[Golden Child]

I was hacking on mame and trying to get 32k roms to work:

https://forums.atariage.com/topic/38438 ... with-mame/

I was also trying to figure out how the 16 way controller worked.


some posts related to the 16 way controller:

viewtopic.php?t=294

https://mametesters.org/view.php?id=7338


The diagnostic b cart doesn't work in mame, but using the debugger, you can bypass some of the checks, setting pc=b5b7 (you may need to do it twice)

g
pc=b5b7
pc=b5b7



I made a spreadsheet of how I think the 16 way controller works:

direction 0 is down, moving CCW

Code: Select all

dir	down	right	up	left	SE	NE	NW	SW	zeros	zerosinorder				
0	1								1	1	253		11111101	FD
1	1				0				10	01	252		11111100	FC
2	1	2			0				120	012	248		11111000	F8
3		2			0				20	02	250		11111010	FA
4		2							2	2	251		11111011	FB
5		2				6			26	26	187		10111011	BB
6		2	3			6			236	236	179		10110011	B3
7			3			6			36	36	183		10110111	B7
8			3						3	3	247		11110111	F7
9			3				4		34	34	231		11100111	E7
10			3	5			4		354	345	199		11000111	C7
11				5			4		54	45	207		11001111	CF
12				5					5	5	223		11011111	DF
13				5				6	56	56	159		10011111	9F
14	1			5				6	156	156	157		10011101	9D
15	1							6	16	16	189		10111101	BD

[cheshirenoir]

Heh. Those threads about the controllers. That was me. I know SO MUCH more about them now, having played with several different controller replacements.

Probably the key piece if info you want is this part of the thread between a bunch of us here.
viewtopic.php?f=13&t=313&start=10#p3001
Scouter3D and Username did all the heavy lifting.

(I have yet another controller project ready to send off to JLCPCB, but I need to wait a little as another project has got "in the way" as it were. I got a laser cutter and that's been stealing all my spare money)

[Golden Child]

Hi Cheshire,

That's a good thread. I've implemented the 16 way joysticks but strangely it doesn't really help in planet defender. It seems to dislike diagonal movements, only moving the ship when its left right or up down.


https://forums.bannister.org/ubbthreads ... Post124816

[leadedsolder]

Have you figured out what the sanity check error ("CRB 80 00, CRB BF 3F") means in MAME?

As far as I can tell, it fails the second test of a test chain that starts at $b437 by retrieving $80 instead of $00 from port $1003. I assume that the other failure, "got $bf expected $3f" is the same issue with the same stuck bit, whatever it is that's there.

I get a different error on my CreatiVision clone on startup, and I'm just now starting on stepping through it in MAME to figure out what the ROM is doing to produce the error.

So far I've figured out the character set in use, which is quite unusual, and unexpectedly seems to be tied to the keyboard layout.