Atari 7800 Secam Question and information help

[Magic Knight]

Hi

 

Im working on an s-Video circuit for the 2600 TIA which is based on the french Secam signal. As Secam is remarkably different from NTSC and PAL this is going to be a completely different one from the existing circuits available. I have the information i need for a 2600 or 7800 on TIA to get this done,

 

So the the TIA circuit as we know is in the 7800 and is easily adaptable, but there appears to be little or no information regarding Secam 7800's where the MARIA chip is concerned.

 

Was there a french Maria chip for secam or was the output from this sent via Piritel(or scart) with a PAL signal outputted?

 

 

Even better - if someone out there has a 7800 Schematic for Secam - that would be the ultimate want for me to proceed further,

 

 

[alex_79]

The 7800 never had a SECAM version. Peritel 7800 consoles sold in France were based on PAL models with a RGB converter board installed instead or the rf modulator.
The cable of the Peritel 7800 only carries RGB and sync, there's no composite video (so neither PAL nor SECAM).

http://atariage.com/forums/topic/163892-rgb-scart-for-the-7800/

[+slx]

The 7800 never had a SECAM version. Peritel 7800 consoles sold in France were based on PAL models with a RGB converter board installed instead or the rf modulator.

The cable of the Peritel 7800 only carries RGB and sync, there's no composite video (so neither PAL nor SECAM).

 

http://atariage.com/forums/topic/163892-rgb-scart-for-the-7800/

As knowledge about the Peritel 7800s seems to be rather scarce any you seem to know about them:

 

Any idea why a Peritel 7800 might display colors in MARIA mode but B/W in TIA mode (and how this might be corrected)?

[Magic Knight]

Thanks - its interesting how the 2600, A8 (XL and XE) series got the secam treatment (albeit a crap selection of colors) and the Maria didnt.

 

I guess the lavish color scheme was too much to dull down to greys for the palette that the Maria gives?

 

For the latest on how to get the best from the Peritel side and avoiding black and white TIA - see here: http://eddystoys.blogspot.com/2014/08/atari-2600.html

 

Its in French but if you download the automatic webpage translator, it comes out fairly understandable (on Mozilla anyhow)