Issue making TMNT 1 MMC3 Reproduction

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Issue making TMNT 1 MMC3 Reproduction
by on (#148807)
I'm using a TLROM board. I applied infidelity's MMC3 patch from v9.1 to Teenage Mutant Ninja Turtles (U).nes and the resulting rom plays fine on my Everdrive N8 and in FECUX.

I split and pad it my normal way using famirom and solder the programmed eprom down using these directions:
PRG ROM:
Pin 1 Nothing!
Pin 2 Hole 24
Pin 24 Pin 16 (or another ground)
Pin 30 Hole 1
Pin 31 Hole 2

CHR ROM:
Pin 1 Nothing!
Pin 2 Hole 24
Pin 22 Hole 31
Pin 24 Hole 2
Pin 30 Hole 1
Pin 31 Nothing!

The resulting game starts but is graphically garbled and then freezes. Tieing A18 and A19 to high/low has no impact.

Here's pics: http://imgur.com/a/Yk7Ma

Anyone have any ideas?
Re: Issue making TMNT 1 MMC3 Reproduction
by on (#148809)
Best guess: bad UVEPROM.
Re: Issue making TMNT 1 MMC3 Reproduction
by on (#148810)
I actually have tried it on 2 different TLROM donor boards and 4 total different eprom, same issue on them all.
I almost feel like it's got to be something with the patch. Which if that's the case I doubt I'd be able to fix it as assembly is a bit over my head
Re: Issue making TMNT 1 MMC3 Reproduction
by on (#148811)
AaronE wrote:
I'm using a TLROM board.

Are you sure? The board in your picture says TLSROM, which is not compatible with the "standard" MMC3 configuration.
Re: Issue making TMNT 1 MMC3 Reproduction
by on (#148812)
Joe wrote:
AaronE wrote:
I'm using a TLROM board.

Are you sure? The board in your picture says TLSROM, which is not compatible with the "standard" MMC3 configuration.

Ah good catch, the other board I tried it on with the same end issue/result is TLROM
http://i.imgur.com/WGSzPHh.jpg
Re: Issue making TMNT 1 MMC3 Reproduction
by on (#148813)
Joe wrote:

TLSROM can be rewired to behave as TLROM and vice versa. Besides, if it were just the TLSROM, the symptoms would be those of wrong mirroring.
Re: Issue making TMNT 1 MMC3 Reproduction
by on (#148851)
That patched rom is using WRAM. You need a TSROM board.
Re: Issue making TMNT 1 MMC3 Reproduction
by on (#148852)
Both famirom and nesmapperprogram showed me no RAM. Is there another way to double check to see if it does need WRAM?
Re: Issue making TMNT 1 MMC3 Reproduction
by on (#148854)
On emulators, the RAM is always there. The bit in the header says if it's battery-backed or not.

To be sure if it uses WRAM, set a breakpoint on accesses to $6000-$7FFF.
Re: Issue making TMNT 1 MMC3 Reproduction
by on (#148856)
ah ok it does have this in debugger as a breakpoint when I set it to 6000 to 7FFF read/write

07:CEAA:8D 00 60 STA $6000 = #$03
Re: Issue making TMNT 1 MMC3 Reproduction
by on (#148885)
AaronE wrote:
Both famirom and nesmapperprogram showed me no RAM. Is there another way to double check to see if it does need WRAM?


famirom can only tell if a rom uses wram if there's a battery, where ram is implied, or the rom builder set the non-standard ram units value. so when it says "not specified" that doesn't mean zero ram, it means neither of those values are set and it can't make a determination.
Re: Issue making TMNT 1 MMC3 Reproduction
by on (#148923)
Ok I put it on a TSROM board and the graphics are even worse than before but I can hear the music of the game running.