Famicom Reproduction Diagrams?

Famicom Reproduction Diagrams?
by Tormenter on 2007-09-30 (#27307)

I have a Famicom game on a HVC-SNROM cart that I wish to reproduce in case it ever goes bad. Are there any wiring diagrams for famicom games anywhere? I noticed there are NES Wiring Diagrams on this site (eprom conversions on nesdev.com part) but I do not see any famicom anywhere. Could someone help me out and point me in the right direction? Or if you know the wiring by chance lol. Thanks!

by Bregalad on 2007-10-01 (#27315)

NES ROM wiring are exactly identical to Famicom ROM wiring as far I know.

by Tormenter on 2007-10-03 (#27336)

Bregalad wrote:
NES ROM wiring are exactly identical to Famicom ROM wiring as far I know.

Ahhh...This one is a HVC-SNROM, which accepts 28 pin eproms, so those couldnt be wired the same =( hehe

by peppers on 2007-10-03 (#27337)

Using this Image of one an example you can see that there are unused through holes next to the PRG ROM
If this game had a larger PRG rom those through holes would be filled with pins of a ROM
Also the HVC-SNROM board used a CHR RAM

Fyi: the mask ROM pinout is the same although since your western and NES carts are easier to some by over here you could just use the NES equivalent

by Tormenter on 2007-10-03 (#27338)

peppers wrote:
Using this Image of one an example you can see that there are unused through holes next to the PRG ROM
If this game had a larger PRG rom those through holes would be filled with pins of a ROM
Also the HVC-SNROM board used a CHR RAM

Fyi: the mask ROM pinout is the same although since your western and NES carts are easier to some by over here you could just use the NES equivalent

I did a direct solder, and I got the cart to work...only one time, and couldnt get it working again. Though I used a chr AND prg. Im confused on this one lol

by Tormenter on 2007-10-03 (#27339)

Btw, thats the EXACT same donor I used....the file size was 64k chr and 32k prg, I used 27c512 and a 27c256

by peppers on 2007-10-03 (#27340)

Tormenter wrote:
Btw, thats the EXACT same donor I used....the file size was 64k chr and 32k prg, I used 27c512 and a 27c256

Why don’t you just say exactly what you are trying to do
things go a lot faster if you do not feel the need to be vague about what your trying to accomplish

by Tormenter on 2007-10-03 (#27341)

peppers wrote:
Tormenter wrote:
Btw, thats the EXACT same donor I used....the file size was 64k chr and 32k prg, I used 27c512 and a 27c256

Why don’t you just say exactly what you are trying to do

there are no mmc1 games with a 64k chr in Japan and the prg is always larger than the chr or the same size

no game like what you are describing exist, things go a lot faster if you do not feel the need to be vague about what your trying to accomplish

It is a Unreleased test cart I have and that is dumped. I will be releasing it after I finish putting it to cart.

The PRG is 32k, and the CHR is 64k (yes, chr is larger), using cajones to split it. I used the donor you shown above in the link.

It is showing the game as:

Logical Length: 98320 bytes
ROM Size: 32768 bytes (2 16k banks)
VROM Size: 65536 byes (8 8k banks)
Memory Mapper: 1 - MMC1
Mirronring: Vertical
4-Page VRAM (none)
Trainer: (none)
Battery RAM: In Use

by Tormenter on 2007-10-03 (#27342)

This is from Nestopia:

CRC: 0xE149E0B2
System: NTSC
Board/Chips: SxROM
Mapper: 1
PRG-ROM: 32k, CRC: 0xAF8F7059
CHR-ROM: 64k, CRC: 0x031F9622
W-RAM: 8k
Mirroring: Vertical

by peppers on 2007-10-03 (#27344)

yes I made i mistake about that chr always being smaller thing and edited it shortley before you replyed

by peppers on 2007-10-03 (#27345)

first problem I see is the board is controlled mirroring and your dump is vertical

btw: did you connect the CHR side correctley when replaceing the RAM with a ROM?

by Tormenter on 2007-10-03 (#27346)

peppers wrote:
first problem I see is the board is controlled mirroring and your dump is vertical

So the donor is set to horizontal only? I switched the mirroring on the rom and it still works great.

What about the wiring? I got a direct solder to work actually, 1 time, then I restarted and could never get it working again

by peppers on 2007-10-03 (#27348)

I edited my last post slightley

I am not an expert but there are 3 types of mirroring vertical, horizontal and controlled (meaning the mirroring is controlled by the program) if the mirroring is not set right the display will be jumbled when trying to play through levels but will often still display menus normaly and will outherwise play right, also if the CHR is not correct the display will be even more jumbled

by Tormenter on 2007-10-03 (#27349)

peppers wrote:
first problem I see is the board is controlled mirroring and your dump is vertical

btw: did you connect the CHR side correctley when replaceing the RAM with a ROM?

How do you mean? I just did a direct solder of the chr and prg slots to the holes. It fired up, only once.

by peppers on 2007-10-03 (#27351)

the PRG side should be correct but I do not think the chr side is (not 100% sure on that though)

what happens when you put the game in the console?

by Lloyd Gordon on 2007-10-03 (#27355)

If it worked once and not again it could be one of the ROM pins wasn't soldered and just made a lucky contact the first time. Try checking each pin and see if the solder flowed normally. Also use a multimeter to check each pin connection. Try not to put any force on the cart when you are checking as the flexing can make an intermittent open solder joint connect.

by Tormenter on 2007-10-03 (#27356)

peppers wrote:
the PRG side should be correct but I do not think the chr side is (not 100% sure on that though)

what happens when you put the game in the console?

Nothing. I fiddled around putting it at different angles etc for several minutes...it FINALLY came on, then I turned power off, and back on, and couldnt get it working again, i tried for about 10 minutes after that. I cleaned connectors etc, so thats not the issue. 2 different systems as well.