Mapper Decap Project

Discuss hardware-related topics, such as development cartridges, CopyNES, PowerPak, EPROMs, or whatever.

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Memblers
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Re: Mapper Decap Project

Post by Memblers »

FrankWDoom wrote: Tue Dec 21, 2021 1:23 pm
Memblers wrote: Sat Dec 18, 2021 1:40 am I could send multiple AX5202P, if that's wanted. If I can find my MTPO cart, I could donate an MMC2. I've had the cart for decades, at some point it quit working (despite any contact cleaning). What seems weird is that I know of two other people who have dead Punchout carts. Could be a coincidence, but cart failures seem to be very rare (excluding obvious visible corrosion etc.), yet it apparently happened to the same game in those cases.
i think i have a couple non-working punchouts (tyson or otherwise, don't recall offhand). have you determined if the roms are ok or not?
I haven't done any testing with it, besides cleaning it and seeing a grey screen. I have a (working) PC10 version also, at one point I thought of maybe swapping the MMC2 onto there to check if it's dead, but lost interest as it seems that shrink-dip sockets were hard to find. It uses EPROM for PRG so can't test that quickly, not without tracing out the ROM select jumpers (assuming this board even supports mask rom).
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org
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Re: Mapper Decap Project

Post by org »

I updated the first post with statistics on parcel shipments. None have arrived yet, I'm looking forward to it :)
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Ben Boldt
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Re: Mapper Decap Project

Post by Ben Boldt »

Thank you org, I will do anything I can to help with MMC5/A. I have been very lucky to come across plenty of both revisions to share and keep for testing now.
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Re: Mapper Decap Project

Post by org »

I decided to check the technique from this video: https://youtu.be/kTPXKA66baQ

Picked the random board from the last package - JY-115. I don't know what's on it, because my Famiclone burned out.

JY-115

by NewRisingSun:
J.Y. cartridges are Taiwanese.
EL860339C is canonically mapper 211, which is identical to mapper 209.
No RAM, only PRG-ROM, CHR-ROM, and the J.Y. ASIC.

https://wiki.nesdev.org/w/index.php?tit ... mpany_ASIC

Research on blobs

Blob 1 - CHR-ROM?

The chip looks smaller than blob_3, so it is most likely a CHR-ROM.

You can't see the mask technology yet, you have to remove the metal.

Blob 2 - ASIC

The chip was bigger than I thought it would be, so when I opened it up, a piece accidentally broke off.

In addition, it was very dirty - the epoxy does not want to come off.

The chip technology is very similar to ASIC logic-arrays:
- The substrate contains transistors stacked in a grid pattern.
- With two top metal layers the transistors are connected in different configurations to form logic gates.

Blob 3 - PRG-ROM?

It looks like a PRG-ROM. You can't see the mask technology yet, you have to remove the metal.



All of the mapper stuff will be here:
https://drive.google.com/drive/folders/ ... sp=sharing
Attachments
asic_40x_logic.jpg
blob1_40x_bonds.jpg
asic_10x_trans.jpg
IMG_5691.png
board_blobs_annotated.jpg
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org
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Re: Mapper Decap Project

Post by org »

Updated the first post with Package1 details.

I'm thinking of opening up the next JY-101 to see how different it is from the JY-115.

I'll start analyzing it when I'm done with the other NES projects.)
I really need to learn the technique of cleaning epoxy off the chips...
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Re: Mapper Decap Project

Post by org »

Clarification on memory chips JY-115.

Blob 1 - PRG-ROM Blob 3 - CHR ROM.

Both memory chips are the same size, but have a slightly different layout.
Both chips seem to use Multi-level memory cells (ion-doped FETs), where one transistor can define several bits. At the output of a row of cells are DC comparators.

That is, you can not dream of a visual dump by picture. Even if you remove the metal - most likely there will be the same "sausages" with different concentration of ion implantation, to set different bit values.

I'll take the metal off one memory chip, just to check.
Attachments
rom_comparators.jpg
rom_cells.jpg
Last edited by org on Sun Jan 30, 2022 4:14 am, edited 2 times in total.
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Re: Mapper Decap Project

Post by org »

Also added a bit to the first post with comments from the parcel's author, on various mappers.
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Re: Mapper Decap Project

Post by org »

I mastered the epoxy surface cleanup, now the datasets should turn out prettier.
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Acetone_Cleaning_clean.jpg
Acetone_Cleaning_dirty.jpg
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Re: Mapper Decap Project

Post by org »

Guys, if you have any priorities on the mappers I've already received, post here. In my spare time, I'll be opening and photographing them one by one.

I will post quality pics of the dirt-cleaned JY ASIC in 40x soon, too.
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Re: Mapper Decap Project

Post by org »

Uploaded JY-115-asic_40x_clean_m2.zip
Mappers/JY-115:
https://drive.google.com/drive/folders/ ... sp=sharing
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Re: Mapper Decap Project

Post by NewRisingSun »

org wrote: Sun Jan 30, 2022 4:32 amGuys, if you have any priorities on the mappers I've already received, post here.
µPD7756 :wink:
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Re: Mapper Decap Project

Post by org »

Made the first pass of lapping on the JY ASIC. The standard cells became visible, I even tried to make a small analysis and immediately found cells very similar to DFF.

Soon will be dataset after the first polishing pass, then there will be another polishing session to remove residual m2.

I also grinded the metal off the ROM. It turned out to be a regular mask ROM with ion implantation, but the cells were very small (I estimate their size at 100-200 nm), at the limit of my microscope.
Attachments
rom_cells.jpg
jy_dff.jpg
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Ben Boldt
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Re: Mapper Decap Project

Post by Ben Boldt »

This is a pretty cool project. Has anything new in the past couple of months?
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org
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Re: Mapper Decap Project

Post by org »

While I'm preparing a book on PPU, here's some research on the topic of mappers.

Source: https://nescartdb.com/profile/view/834/bomberman

A similar approach will be used to find out the pin assignments of the chip that is under the epoxy blob.
Attachments
NES-NROM-128-04-Bomberman.xml
(175.31 KiB) Downloaded 29 times
2.png
1.png
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Ben Boldt
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Re: Mapper Decap Project

Post by Ben Boldt »

Do you know about KrzysioPCB made by krzysiobal? It is similar visual PCB tracing tool with direct connection to Eagle so you can turn it easily into a schematic.
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