Jump to content

Photo

Atari SECAM computers


29 replies to this topic

#1 DyLucke OFFLINE  

DyLucke

    Space Invader

  • 28 posts

Posted Thu Nov 10, 2011 8:44 AM

Hi i would like to ask if there's any unexpensive way to use a SECAM 800XL or 130XE computer on a PAL TFT TV.

I've just acquired a couple of these computers and i've realized they're SECAM,
they came with a Monitor-SCART cable (6pin)
the video is shown but some colours are displayed in the wrong way.

Maybe the S-Video hack could fix the problem?

Thanks!

#2 Rybags ONLINE  

Rybags

    Quadrunner

  • 12,885 posts
  • Location:Australia

Posted Thu Nov 10, 2011 8:51 AM

Secam video is somewhat different from PAL.

The best chance would be if the TV has a system setting to use Secam, but from gear I've seen they typically only have PAL/NTSC.

But if you're in a European country then things are probably different.

#3 DyLucke OFFLINE  

DyLucke

    Space Invader

  • Topic Starter
  • 28 posts

Posted Thu Nov 10, 2011 8:59 AM

Well yep, i'm from Spain and the video system here is PAL, however NTSC can be displayed thru the SCART socket.

I don't know a single thing about SECAM, but i can see the SECAM computers i have here have a round 6pin plug instead the usual 5pin
for PAL computers. I'm not sure they can work on SECAM mode either. SECAM is used in France and Russia.

The cable provided with the computers is clearlly crafted to be used with SECAM ataris ON SECAM TVs thru the SCART socket,
however what i'm wondering is if some kind of rewiring or internal Atari hacking would make it work on a PAL TV.

Edited by DyLucke, Thu Nov 10, 2011 9:00 AM.


#4 Rybags ONLINE  

Rybags

    Quadrunner

  • 12,885 posts
  • Location:Australia

Posted Thu Nov 10, 2011 9:28 AM

The GTIA in Secam machines is significantly different also.

To accomodate the extra signalling needed, the joystick buttons are read serially through a single pin instead of the usual 4 pins.

So, you can't put a PAL GTIA in.

The Secam Ataris are not really explored to the extent of PAL/NTSC ones - I think someone's posted pics of a Secam motherboard, but aside from that and the FGTIA.PDF document, there's not a great deal of info around about them.

#5 orpheuswaking OFFLINE  

orpheuswaking

    River Patroller

  • 4,747 posts
  • Lone Raider Time!
  • Location:Indianapolis, Indiana, USA

Posted Thu Nov 10, 2011 9:38 AM

As far as I know you would need a SECAM tv to make those work.

Edited by orpheuswaking, Thu Nov 10, 2011 9:42 AM.


#6 Thorsten GŁnther OFFLINE  

Thorsten GŁnther

    Dragonstomper

  • 907 posts
  • Location:Wedel, Germany

Posted Thu Nov 10, 2011 9:52 AM

As far as I know you would need a SECAM tv to make those work.


Modern TVs in Europe are usually PAL/SECAM/NTSC compatible anyways (at least through AV inputs) and have been for quite some time (I know my first large CRT TV - a Panasonic TX-28LD4C, was and all my current ones are).

#7 Simius OFFLINE  

Simius

    Chopper Commander

  • 165 posts
  • Location:Warszawa, Poland

Posted Thu Nov 10, 2011 10:23 AM

The Secam Ataris are not really explored to the extent of PAL/NTSC ones


However, there are some experiences:
digital FGTIA SECAM-RGB adapter.
digital FGTIA SECAM-RGB adapter with scandoubling.

#8 DyLucke OFFLINE  

DyLucke

    Space Invader

  • Topic Starter
  • 28 posts

Posted Thu Nov 10, 2011 10:34 AM

Gosh, these adaptors look great, however i don't understand a single word in polish, and they seem to be expensive.

I've tried both computers on a Samsung T200HD and a Sony Bravia 32" with the same results, image is displayed but colours are wrong.
Sometimes green colour seems to be missing, sometimes red seems to be missing.
I guess if the TV was non SECAM compatible wouldn't show a shit on screen... But it actually does the work mostly.

I'll post some pictures in a while to show what i mean.

#9 mimo OFFLINE  

mimo

    Preppie!

  • 6,778 posts
  • It's easy living in a bubble

Posted Thu Nov 10, 2011 10:35 AM

send one to me, I have a SECAM TV :grin:

#10 orpheuswaking OFFLINE  

orpheuswaking

    River Patroller

  • 4,747 posts
  • Lone Raider Time!
  • Location:Indianapolis, Indiana, USA

Posted Thu Nov 10, 2011 10:39 AM

I guess if the TV was non SECAM compatible wouldn't show a shit on screen... But it actually does the work mostly.


Not necessarily, putting a PAL XL on a NTSC monitor it shows in black and white... Probably something similar with Secam on PAL. Not 100% sure though.

#11 mimo OFFLINE  

mimo

    Preppie!

  • 6,778 posts
  • It's easy living in a bubble

Posted Thu Nov 10, 2011 10:52 AM

Gosh, these adaptors look great, however i don't understand a single word in polish, and they seem to be expensive.

I've tried both computers on a Samsung T200HD and a Sony Bravia 32" with the same results, image is displayed but colours are wrong.
Sometimes green colour seems to be missing, sometimes red seems to be missing.
I guess if the TV was non SECAM compatible wouldn't show a shit on screen... But it actually does the work mostly.

I'll post some pictures in a while to show what i mean.


Is the colour issue not down to them being a SECAM system? I thought that the SECAM systems only have 16 colours available?

#12 DyLucke OFFLINE  

DyLucke

    Space Invader

  • Topic Starter
  • 28 posts

Posted Thu Nov 10, 2011 11:12 AM

SECAM Ataris:
Posted Image

PAL Atari:
Posted Image


SECAM Ataris:
Posted Image

PAL Atari:
Posted Image


SECAM Ataris:
Posted Image

PAL Atari:
Posted Image


Any idea? Something wrong with the cable maybe?

#13 DyLucke OFFLINE  

DyLucke

    Space Invader

  • Topic Starter
  • 28 posts

Posted Thu Nov 10, 2011 11:16 AM

Another sample:

SECAM Ataris:
Posted Image

PAL Atari:
Posted Image

#14 DyLucke OFFLINE  

DyLucke

    Space Invader

  • Topic Starter
  • 28 posts

Posted Thu Nov 10, 2011 11:17 AM

Forgive me for the low quality of the pictures, i should have used the camera instead this stupid cellphone.

#15 rdea6 ONLINE  

rdea6

    Stargunner

  • 1,671 posts
  • Location:Arizona USA

Posted Thu Nov 10, 2011 11:44 AM

Have you tried adjusting the color pot through the small hole on the bottom of the Atari.??

#16 DyLucke OFFLINE  

DyLucke

    Space Invader

  • Topic Starter
  • 28 posts

Posted Thu Nov 10, 2011 12:05 PM

The only adjustable thing on this computer is a switch to turn it to B/W or Colour. Maybe i'm missing something.

Edited by DyLucke, Thu Nov 10, 2011 12:18 PM.


#17 rdea6 ONLINE  

rdea6

    Stargunner

  • 1,671 posts
  • Location:Arizona USA

Posted Thu Nov 10, 2011 1:01 PM

Have look at this link: ---- http://atarinside.dy..._serialNumber=3

Secam mother board shows a color vsync pot.

#18 DyLucke OFFLINE  

DyLucke

    Space Invader

  • Topic Starter
  • 28 posts

Posted Thu Nov 10, 2011 2:02 PM

WTF? I have to check this out... Now i don't have the time, i'll post you back in a couple of days. Thanks for the info, i'll give it a try.

#19 StaxX28 OFFLINE  

StaxX28

    Chopper Commander

  • 166 posts
  • Location:France

Posted Thu Nov 10, 2011 3:52 PM

It's normal, every SECAM XL/XE have this 'problem'!

Jerry Jessop explains why French Ataris produce fewer colors:
I will tell you why it only has monochrome out, because it's SECAM and a
SECAM GTIA was never produced. The PAL GTIA is used in France and the Lum
outputs are run into an onboard encoder to produce a "psudo" color depending
on the Luminance output, composite only. This is why a SECAM VCS or 800 has
nowhere near the same number of colors (16) availible as a PAL or NTSC unit

http://www.classiccm...ixl/atari8b.txt

#20 Simius OFFLINE  

Simius

    Chopper Commander

  • 165 posts
  • Location:Warszawa, Poland

Posted Thu Nov 10, 2011 4:20 PM

That isn't true. SECAM FGTIA produce pallette of 120 colors (15 colors x 8 intensity levels) and there is possibility to expand this to 240.

#21 orpheuswaking OFFLINE  

orpheuswaking

    River Patroller

  • 4,747 posts
  • Lone Raider Time!
  • Location:Indianapolis, Indiana, USA

Posted Thu Nov 10, 2011 4:45 PM

But maybe that explains why the games he's running are showing vibrant colors, just wrong...

#22 DyLucke OFFLINE  

DyLucke

    Space Invader

  • Topic Starter
  • 28 posts

Posted Thu Nov 10, 2011 4:58 PM

I've reduced a lot the vibrant colors messing with the color pot, but if nothing is wrong with the video cable, some colours are shown totally different from a PAL screen.
Probably FGTIA has some similar issue to the 2600's TIA that performed a different pallette.
I don't believe it has less colours than the GTIA, that would mean the missing colours from the pallette would be shown in black or on other different colour that could seem absolutelly wrong.
The question is this isn't happening it's more like just the pallette has some colours that are different, probably as a result of the way SECAM manages colour in comparison to PAL.

I'll get another video cable and we will finally figure what happens here. It doesn't seem a problem with the TVs neither a problem with both SECAM Ataris, bec they perform in the same way.

By the way Simius, these video boards are being produced? What's the price for one unit? What kind of video output does it provide?
It reminds me a bit the "Individsion" for the Amiga computers.

#23 Simius OFFLINE  

Simius

    Chopper Commander

  • 165 posts
  • Location:Warszawa, Poland

Posted Thu Nov 10, 2011 5:01 PM

But maybe that explains why the games he's running are showing vibrant colors, just wrong...

Rather because SECAM palette is other than PAL and NTSC.

Edited by Simius, Thu Nov 10, 2011 5:01 PM.


#24 orpheuswaking OFFLINE  

orpheuswaking

    River Patroller

  • 4,747 posts
  • Lone Raider Time!
  • Location:Indianapolis, Indiana, USA

Posted Thu Nov 10, 2011 5:06 PM

Or maybe Secam users prefer to see an ocean of blood in karateka rather than the normal blue :D

#25 Rybags ONLINE  

Rybags

    Quadrunner

  • 12,885 posts
  • Location:Australia

Posted Thu Nov 10, 2011 5:11 PM

Secam transmits the (Y-R) and (Y-B) signal on alternate scanlines, so I guess it's feasible for non compatible TVs to return all kind of weird results.

One of the 256 colour chart programs is what you should run on it - that way some sense could be made of what's going on.




0 user(s) are browsing this forum

0 members, 0 guests, 0 anonymous users