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PostPosted: Tue Jan 05, 2016 8:20 am 
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Hi!! I'm just trying to do a Legend of Zelda repro from a portuguese translated ROM by Hexagon I got from NesNinja site.
I used this board from "Gol de Craque", a Jaleco's Goal pirated version sold by Gradiente here in Brazil:
Front of the board: https://drive.google.com/open?id=0B0OtM ... 0M5OE92LWc
Back of the board: https://drive.google.com/open?id=0B0OtM ... DU4cG1mblE
I have done some rewiring on the board, following this schematics:
http://www43.tok2.com/home/cmpslv/Famic/Fcmp1.png
For the ROM I used a P28f001, PRG RAM is a KMS6264A-12 and CHR RAM is a KM6264BL-10.

So far so good the game only boots if I add R1, a 10k resistor, as show in the schematics, but when I press start it just locks out.
If I leave it alone, it locks on the treasures screen.
I just can't imagine what can be wrong.
Anyone has any ideas of what can be happening?
Are the schematics I followed correct?
I've not put the battery on the board yet, but I think this could not be doing all this trouble.
Thanks in advance!


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PostPosted: Tue Jan 05, 2016 1:51 pm 
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I'm not very familiar with what you are doing but depending on the size of the translation couldn't you just split the rom into 2 files and toss on two 27c801 and swap bin them and toss on a troy aikmen cart? Or is it too big a file for that?


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PostPosted: Tue Jan 05, 2016 2:07 pm 
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The original game is 1Mibit, as is the translation.

It's not SNES, one doesn't need 8Mibit 'PROMs.


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PostPosted: Tue Jan 05, 2016 2:12 pm 
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The size is fine, it's just a 1mbit image. The memory you suggested AFAIK is a 8mbit.
A lot bigger than needed.
I'll try to use both RAMs with 2x the same ICs...
I don't see much logic in this but...
I'm just running out of ideas!

Maybe the cloned MMC1 has a glitched SRAM control logic...
Or there's some address lines incorrect?
I just had not touched the address and data lines...
Only the ROM's A16 and the control lines of the RAMs, should I mod it someway?


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PostPosted: Tue Jan 05, 2016 2:28 pm 
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It's remotely plausible that the clone MMC1 emits WRAM/CE rather than WRAM+CE.

But I really don't know, it seems at least as likely that the chip-on-board is some non-MMC1 thing and that the original was mapper hacked for the original Gol de Craque port.


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PostPosted: Tue Jan 05, 2016 4:01 pm 
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Yeah sorry I assumed this was snes. I should have read it a little better.

Can you use a normal ntsc donor? If you can nes open golf and golf power should be good donors. You would just rewire the prg as follows.


SNROM (mapper 1):
Bend up pins 1, 2, 24, 30 and 31 (or cut tracks 2, 24 and 30)
Solder pin 2 to hole 24 (A16)
Solder pin 24 to GND (OE)
Solder pin 30 to hole 1 (A17)

edit: that if for m27c eproms. Not sure about the eprom you use.

Unfortunately I am not familiar with the boards and chips you are using so I will not be of much help.


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PostPosted: Tue Jan 05, 2016 4:33 pm 
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lidnariq, is there some way to confirm this?
AFAIK this MMC1 clone has both CE and /CE.
I don't know if it's functional.
Before doing this repro, I tried Chip n' Dale on this board.
I even had finished the game.
It may be just a subset of MMC1 though...

icemanxp300: Yeah! I could be using official NES carts, it even seems easier to mod.
But they are too expansive here, around 100 bucks each!
That's why I'm stuck with the cheap pirates, or it would be like declaring war on my wife! :-b


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PostPosted: Tue Jan 05, 2016 5:08 pm 
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Location: NE Indiana, USA (NTSC)
SLROM: MMC1 with CHR ROM
SKROM: MMC1 with CHR ROM and WRAM
SKROM with battery: MMC1 with CHR ROM and battery-backed WRAM
SGROM: MMC1 with CHR RAM
SNROM: MMC1 with CHR RAM and WRAM
SNROM with battery: MMC1 with CHR RAM and battery-backed WRAM

Both Chip 'n Dale games are SLROM. For The Legend of Zelda, you want SNROM with battery. For Zelda II: The Adventure of Link, you want SKROM with battery.


A MySQL configuration limit is preventing this post from appearing as intended. I will report it in phpBB issues.


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PostPosted: Tue Jan 05, 2016 5:22 pm 
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Maybe try making a reproduction of an SKROM board?

Alternatively, could you use the pinouts on the wiki with a continuity meter
- http://wiki.nesdev.com/w/index.php/MMC1_pinout
- http://wiki.nesdev.com/w/index.php/Mask_ROM_pinout
- http://wiki.nesdev.com/w/index.php/6264_static_RAM

to see if the supposed chip-on-board MMC1 matches up?

SNROM "should" have both /CE (pin 11, actually CHR A16) and +CE (pin 6) outputs.


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PostPosted: Tue Jan 05, 2016 6:18 pm 
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lidnariq wrote:
Maybe try making a reproduction of an SKROM board?


Will that work? Zelda uses onboard chr ram where as skrom has chr rom.


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PostPosted: Tue Jan 05, 2016 6:34 pm 
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Location: NE Indiana, USA (NTSC)
It'll work if you skip The Legend of Zelda and instead make Zelda II: The Adventure of Link.


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PostPosted: Tue Jan 05, 2016 6:59 pm 
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Right, I just meant "test with another game"


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PostPosted: Wed Jan 06, 2016 6:10 am 
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What I have done to the board up to now (according to my to-do list):
PRG ROM:
Cut the trace to the old A16 on the 28 pin chip (22), bridged the trace to the 32 pin's chip pin 2.
Bridged the 32 pin IC pín 24 to pin 22.
Made 4 holes on the board, so I don't need to bend the IC pins.

CHR RAM:
Cut the pin 22 trace and bridged to /RD.
Bridged pin 20 to PA13.
Cut pin 27 trace (was going to MMC1 pin 9) and bridged to PPU /WE.
Disconnected pin 26 from MMC1 pin 8 and bridged to VCC.
Bridged pin 1 and 28.

PRG RAM:
Cut the trace on pin 22 and bridged to GND.
Cut the trace on pin 26 from MMC1 pin 22 and bridged to MMC1 pin 6.
Cut the trace on pin 27 from MMC1 pin 1 and bridged to MMC1 pin 17.
Cut the trace on pin 20 and bridged to MMC1 pin 11.
Bridged pin 1 and 28.
Cut the VCC trace and added a diode to it.

As far as I remember, I have not done anything else besides adding R1 and R3.
The traces I have cutted that were going to the PRG ROM where later rebridged to the ROM, leaving some more traces that goes to PRG RAM alone.
I'll try another game, it may be the translation that has some bugs...
Should change the PRG RAM (or WRAM) to the CHR RAM's same IC model be a good idea too?


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PostPosted: Sat Jan 09, 2016 1:29 pm 
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Weird thing happened:
I changed the PRG RAM IC, so, both RAMs are the same part, speed...
At first it was the same, than I removed R1 and R2.
The game stopped locking on presentation, has some graphical glitches, but works.
Then, at the name entry there are 3 names wich I can't select.
I erased them all and tried to create a new one, but as soon as I finish the names appear again with weird chatacters and I can't start the game.
Is this game timing critical?
Why such difference with a slight faster RAM?
Very weird!!


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PostPosted: Mon Feb 15, 2016 4:03 am 
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After my vacations, I'll try to resume this project.
I'll try Metroid in this board this evening.
Just in case someone is interested in the results I got with Zelda, I'm posting some small videos on YouTube:
Intro: https://youtu.be/qv0MgqCEbgg
Name entry: https://youtu.be/BuJ_kjjr-pw
Gameplay: https://youtu.be/WJLmb4W9Bto

I would be glad if someone could give me something to at least start debugging it.
Thanks in advance!!


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