Page 1 of 3

Famicom AV, PAL NES & Dendy chips decapsulation (progress!)

Posted: Sun Aug 30, 2015 12:36 am
by Eugene.S
Hi, nesdev!
I've contacted to http://zeptobars.ru/en/ project about half-year ago.

I gave to them some chips for decapsulation, and now we have first results.
-------------------------------------------------------------------------------------------------------------------------------------------------------------
Chips:

RP2A03H - Famicom AV "rev H" CPU
RP2C02H-0 - Famicom AV "rev H" PPU
RP2C07-0 - French version PAL NES PPU
(PPU itself output is standard composite signal, but finally converted to RGB by special decoder on NES mainboard)
Red/green emphasis bits are swapped.

UMC UA6527P - Hybrid ("Dendy") CPU made by "UMC". I know it has better DPCM, timbre and overall sound quality than TA-03NP1, but has 25%<->50% duty cycles swapped
UMC UA6538 - Hybrid ("Dendy") PPU made by "UMC". I've confirmed red/green emphasis swap on it. It has more saturated palette than TA02-NP-6538 and RP2C07-0.

TA-03NP1-6527P - Hybrid ("Dendy") CPU made by "TA". I know it has worse timbre and buggy DPCM than UMC UA6527P, but has right dutycycles
TA-02NP-6538 - Hybrid ("Dendy") PPU made by "TA". It has red/green emphasis bits also swapped, as well as RP2C07-0 and UA6538.
-------------------------------------------------------------------------------------------------------------------------------------------------------------

First photos of UMC UA6538 PPU:
METAL LAYER: http://s.zeptobars.ru/UMC-UA6538-HD.jpg
If everything is clear with the current view, and it can be properly reversed, zeptobars will remove metallization layer and go ahead to the polysilicon.

Re: Famicom AV and Dendy chips decapsulation (progress!)

Posted: Sun Aug 30, 2015 1:58 am
by HardWareMan
Awesome! I want to know the difference between that chips.

Re: Famicom AV and Dendy chips decapsulation (progress!)

Posted: Sun Aug 30, 2015 6:04 am
by Quietust
The metal image for that PPU is a bit blurry compared to the image I used for Visual 2C02, but hopefully it should be good enough for tracing, especially since the "core" of the chip seems to be an almost exact clone of the RP2C02, with differences being mostly in the interconnects and the pin drivers.

Re: Famicom AV and Dendy chips decapsulation (progress!)

Posted: Sun Aug 30, 2015 6:51 am
by feos
Quietust wrote:The metal image for that PPU is a bit blurry compared to the image I used for Visual 2C02, but hopefully it should be good enough for tracing, especially since the "core" of the chip seems to be an almost exact clone of the RP2C02, with differences being mostly in the interconnects and the pin drivers.
Since further steps couldn't be undone, they guy who's doing the work needs absolute approval and confirmation. Your post is one, right?

Re: Famicom AV and Dendy chips decapsulation (progress!)

Posted: Sun Aug 30, 2015 11:18 am
by org
I found some stitching errors :

Image

But anyway this image looks suitable for reversing to me :)

Re: Famicom AV and Dendy chips decapsulation (progress!)

Posted: Wed Sep 02, 2015 9:21 am
by barsmonster
org wrote:I found some stitching errors :
That is exactly what I was afraid of. Can you show where on the die you've found this?

Re: Famicom AV and Dendy chips decapsulation (progress!)

Posted: Thu Sep 03, 2015 1:41 pm
by org
Image

Re: Famicom AV and Dendy chips decapsulation (progress!)

Posted: Thu Sep 03, 2015 2:03 pm
by feos
Google wrote:Forbidden That’s all we know.

Re: Famicom AV and Dendy chips decapsulation (progress!)

Posted: Thu Sep 03, 2015 6:12 pm
by Eugene.S
I've dug up the roots - all the rivers flocking to TXC corporation:

Seems TXC "developed" first clone-chips itself in late 80s, and it was:
MG-P-501 (CPU) photo1
MG-P-502 (PPU) photo2
I need to find these chips for testing, and make 100% sure about hybrid or ntsc timings they have.
I know that some MicroGenius consoles was pure NTSC (6527+6528), but some have (6527P+6538) hybrids.

TXC also developed original games, like Journey to the West (Asia) (Unl)

I'm waiting for original RP2C07-0 to decap it too.

Re: Famicom AV and Dendy chips decapsulation (progress!)

Posted: Fri Sep 04, 2015 6:43 am
by org
Ugh :/

Image

Re: Famicom AV and Dendy chips decapsulation (progress!)

Posted: Sat Sep 05, 2015 1:18 pm
by Eugene.S
Piroxilin just confirmed red\green emphasis bits swap on TA-02NP 6538.
So, it has same behaviour as RP2C07 and UMC version of hybrid PPU (UA6538).
I guessed famiclone chips was RP2C07 copied, + timings adjusted to be NTSC/PAL hybrid.

I've also confirmed emphasis bits swap on RP2C07-0

Re: Famicom AV, PAL NES & Dendy chips decapsulation (progres

Posted: Tue Sep 29, 2015 8:10 am
by barsmonster
Redid metal:

http://s.zeptobars.ru/UMC-UA6538-2.jpg
http://s.zeptobars.ru/UMC-UA6538-2-HD50.jpg
http://s.zeptobars.ru/UMC-UA6538-2-HD.jpg

HD50 - is half resolution (like it was before), HD - full resolution (0.25Gb).
Full resolution is exceeding optical resolution limit, so we probably not loosing much.
Pending sign-off for etch.

Re: Famicom AV, PAL NES & Dendy chips decapsulation (progres

Posted: Tue Sep 29, 2015 10:49 am
by 2600
I'm interested in seeing what the RP2A03H differences are.

Famicom AV, PAL NES & Dendy chips decapsulation (progress)

Posted: Tue Sep 29, 2015 11:55 am
by Eugene.S
Sure, but we need 2C07 first: http://www.qmtpro.com/~nes/chipimages/#rp2c07
The Visual6502 project has one of these chips depackaged, but no plans to delayer or photograph it have been announced.
And i'm personally interested to find differences between "Dendy" and official NES.
Timings of NTSC/PAL hybrid famiclones are unique. We need to do good research.

Re: Famicom AV, PAL NES & Dendy chips decapsulation (progres

Posted: Tue Sep 29, 2015 2:35 pm
by barsmonster
barsmonster wrote:Redid metal:

http://s.zeptobars.ru/UMC-UA6538-2.jpg
http://s.zeptobars.ru/UMC-UA6538-2-HD50.jpg
http://s.zeptobars.ru/UMC-UA6538-2-HD.jpg

HD50 - is half resolution (like it was before), HD - full resolution (0.25Gb).
Full resolution is exceeding optical resolution limit, so we probably not loosing much.
Pending sign-off for etch.
Doh, on fresh eye found different stitching error :roll: