Article: French -RGB- NES

Started by jpx72, October 13, 2011, 12:11:49 am

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jpx72

October 13, 2011, 12:11:49 am Last Edit: October 13, 2011, 04:41:04 am by jpx72
All credits to dic-sc7 from http://www.forum.emunes.pl

Raw translation of this topic, may contain mistakes (both grammatical and contentual). Author has been notified and agrees with my attempt (I asked about doing an article on FW and he agrees).
I did it because I still think there is too few informations about the French RGB NES, actually this is the second article I've found do far. If somebody can play with it, it can be a nice article for the main FW page... don't you think? Of course theres THIS ARTICLE too: http://blog.hardcoregaming101.net/2009/12/french-nes-with-rgb-output.html so maybe combining those two together somehow... :bub:



French NES has been manufactured in a special way. "FRA" console is the only NES manufactured with a RGB output. This was the only way to introduce it to the French market. Common knowledge is that French TV color system is SECAM (being slowly eliminated these days). Nintendo had to manufacture a special version of PPU and that wasn't really economicaly acceptable. In those days, SECAM was used in France and its colonies, but also in former Soviet Union and its satelites (Eastern Bloc countries). Nintendo decided not to distribute the console by themselves, but this task was entrusted to a French branch of BANDAI.

Technical details:

  • Mainboard version: PAL-EEC "NES-CPU-11"

  • CIC lockout chip: 3195Av (with additional protection agains some pirate carts)

  • CPU and PPU identical to other console versions (FRG, NOE, GBR - PAL)
    CPU - RP2A07A
    PPU - RP2C07-0

  • Xtal - KDS 26,601712



The cover itself is the same as NTSC version, no distinguishable markings or changes from an ordinary NES.

Console lacks RF modulator and RCA output connectors. There is a special Nintendo-standard 10-pin connector instead. Cable for connecting the console with TV is a special 10-line cable ended with male SCART connector, carrying both audio and video (RGB). Original French AV cable pinout (colors match original) in attachment.

Instead of a RF modulator, this console has a decoder build around Sony V7021 (28-pin SDIP) PAL/NTSC to RGB decoder (used in Commodore and Amiga equipment). Pinout of the Sony V7021:
1 GND1
2 SYNC OUT
3 BF OUT
4 ACK TC
5 TP ADJ
6 Vcc1
7 ALT PLS OUT
8 Vcc3
9 APC TC
10 HUE ADJ
11 VXO 2
12 VXO 1
13 GND3
14 SC OUT
15 GND2
16 R OUT
17 G OUT
18 B OUT
19 DLA IN
20 DLA BIAS
21 CHROMA OUT
22 Vcc2
23 CHROMA ADJ
24 CHROMA IN
25 ACC TC
26 TC 2
27 VIDEO IN
28 TC 1


It's proven that by exchanging the CPU, PPU and Xtal from a NTSC console, the French NES can be converted to output NTSC signal, but some minor changes to Sony V7021 connections must be made (Ref: http://www.forum.emunes.pl/index.php?topic=3771.0).

A couple of words about picture quality of standard FRA console:
 Colors are more saturated (actually good thing)
 Contrast looks better too, and furthermore it changes the way of displaying upper and lower margins(???).

After changing the console to NTSC, the results worsen:
- Contrast is superb, but the colours are not right, especially the red colour.


satoshi_matrix

Thanks for posting this. I lovvvvvvvvve looking at strange motherboards. It's total nerd porn. one thing you didn't mention that's important: the French NES doesn't have a true RGB encoder; what's being feed along the RGB output via the SCART signal is a composite signal. Obviously I don't own a French NES, but I would guess that the colors being off has to do encoding/decoding issues with SECAM.

Did you watch the Dendy documentary I posted? The Russian gentleman shows to much comedic effect how SECAM ruined his childhood.  :D

jpx72

Quote from: satoshi_matrix on October 13, 2011, 01:55:50 am
Did you watch the Dendy documentary I posted? The Russian gentleman shows to much comedic effect how SECAM ruined his childhood.  :D

:D no , but I surely will watch that!

This is exact translation, nothing (only the pinout) is added to it, so combining this info with some other informations may make a very interesting addition to the FW main articles.  
We do have a topic where this has been discussed before http://www.famicomworld.com/forum/index.php?topic=6211.0
And yes, it's not true RGB, but it's still RGB, although it's made out of composite signal. The output on the scart cable IS RGB, not composite, AFAIK...if you look on the connector drawing closely, you have to have a TV that has RGB input to display this. That also means that this output can be connected to an Arcade RGB monitor,although the quality of picture will be similar to composite.

io

I can tell that RGB from french NES is crappy, you can't do real RGB quality from a composite signal.
That's why composite is really better with this console.

QuoteAfter changing the console to NTSC, the results worsen:
- Contrast is superb, but the colours are not right, especially the red colour.

Did you see that too jpx72 when you did your PAL with NTSC components NES ?

jpx72

Quote from: io on November 22, 2011, 06:17:29 am
Did you see that too jpx72 when you did your PAL with NTSC components NES ?

My mod has been done to a German PAL NES without RGB output, and the quality of image (after NTSC-izing) was preserved = the same as original.

io

Good if quality is the same for composite output after switching to NTSC, that's what I was worried about.