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LaTraille

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Hello,

Anyone has attempted this conversion? I see many variations of the daughter boards (2, 4, 8 roms...). Nebulas Ray usually has 8 but the picture on arcademodbios shows a conversion with two...

Thanks!
 
http://postimg.cc/image/3ua9edbjr/

I've seen a conversion like this that sold on another forum, seems to have two MX26L6420 at 64mbit instead of 8 roms of 8mbit like the MAME romset, with what seems to me pins /WE and /BYTE set to HIGH, and probably a 3.3v regulator underneath for Vcc.

I don't know if simply combining the high and low roms into one single eprom a piece will be sufficient or if there needs to be some code altered in the game program to make this intervention possible.
 
http://postimg.cc/image/3ua9edbjr/

I've seen a conversion like this that sold on another forum, seems to have two MX26L6420 at 64mbit instead of 8 roms of 8mbit like the MAME romset, with what seems to me pins /WE and /BYTE set to HIGH, and probably a 3.3v regulator underneath for Vcc.

I don't know if simply combining the high and low roms into one single eprom a piece will be sufficient or if there needs to be some code altered in the game program to make this intervention possible.
That picture was taken by me and portraits my conversion I made some time ago, I still have it hereI used a 3.3V voltage regulator, two MX26L6420 on smaller revision of OBJECT board.Obviously I use a patched ROM set to by-pass the custom KEY chip.Lastly I merged the MAME OBJECT ROMs in two files.
 
That picture was taken by me and portraits my conversion I made some time ago, I still have it hereI used a 3.3V voltage regulator, two MX26L6420 on smaller revision of OBJECT board.Obviously I use a patched ROM set to by-pass the custom KEY chip.Lastly I merged the MAME OBJECT ROMs in two files.
Very cool ! :) Small world. Do you know if the MAME rom files are patched ?
 
They have been not publicly released.So this mean yo have throw your money to someone... :)
 
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So always being interested in conversion ROMs potentially leading to multi-kits, I took a look at the NB-1 games list...
Uh, yeah it's only good game IMO IS Nebula's Ray (aka convert all the boards into NR, abandon pursuit of multi). X/
 
So always being interested in conversion ROMs potentially leading to multi-kits, I took a look at the NB-1 games list...
Uh, yeah it's only good game IMO IS Nebula's Ray (aka convert all the boards into NR, abandon pursuit of multi). X/
Yeah all other games are kinda crap, or should I say, I wouldn't want to play or have in my collection. :P
 
I took a look at the NB-1 games list...
Uh, yeah it's only good game IMO IS Nebula's Ray
Well, Point Blank isn't bad, but it does require a gun cab.
The real shame is that the NB-2 hardware which is nearly identical to NB-1 is what runs both Mach Breakers and Outfoxies... and nothing else that could be converted to either of those two :-/
 
Here are the patched program ROMs (World version):

(now with fixed stars)
http://www.filedropper.com/nbrprothack_1

Tested in MAME only (I don't own the hardware).

Donations are welcome if you like my work and want to support me (paypal apocalypse-mods@outlook.co.nz)

[EDIT]
Played it a bit, this game is awesome!

[EDIT 2]
Only difference I've found is some stars in the background are supposed to be displayed randomly according to values coming from the keycus.

0000.png


In the patched version they are aligned (no RNG).
Of course this could be circumvented by adding a subroutine generating "random" numbers using whatever fluctuating value I can find in RAM as seed for instance.

0001.png


[EDIT 3]
Random values are read from the keycus @ 0x3ACC in program ROMs then rotated left by one bit and ANDed with 0x1ff and finally written to RAM @ 23A6E6 (0x100 bytes).
We could store a set of "random" variables in ROM, not sure what other impact it has in game, there doesn't seem to be any RNG regarding enemies pattern from what I've played.

[EDIT 4]
Fixed the stars, link updated.
 
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Hi :

Does this mean ican concert j league v shootout to a rebula ray and donate to a worthy cause all in the roll of the dice?


Regards
Euphoria
:rolleyes:
 
I recently picked up a Super World Stadium to attempt this conversion. It has the smaller 2-chip OBJECT board I'd like to merge the OBJECT ROMs to use this smaller board the way @caius did.

Is this just a matter of concatenating the upper and lower banks?
nr1obj0u + nr1obj1u + nr1obj2u + nr1obj3u = upper.bin
nr1obj0l + nr1obj1l + nr1obj2l + nr1obj3l = lower.bin

or is it more involved than that?
 
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Logically thinking, that's how I would have thought the object roms would be consolidated but I'm sure someone more knowledgeable will chime in and confirm.
 
I think that's how it works.
Is this just a matter of concatenating the upper and lower banks?

nr1obj0u + nr1obj1u + nr1obj2u + nr1obj3u = upper.bin
nr1obj0l + nr1obj1l + nr1obj2l + nr1obj3l = lower.bin

or is it more involved than that?
 
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