Commodore 128 Alive!

Commodore 128 => Herdware => Topic started by: Andrew Sutton on December 30, 2007, 01:33 PM

Title: RGBI to Component video on TV?
Post by: Andrew Sutton on December 30, 2007, 01:33 PM
I just got my C128 (I know, 22 years late!!), and have been tinkering with video setups. RF clearly stinks. I got a monitor cable, and combined the luma and composite out and hooked it up to AV on my TV. It worked, but had "shadows" in 128 mode. In C64 mode, it was nice and sharp. Must be a quirk with the 8563!
Now for the good(?) part. Would it be possible to make an RGB cable to connect to component video on a TV?
Title: RGBI to Component video on TV?
Post by: Andrew Sutton on December 30, 2007, 02:02 PM
I'm probably barking up the wrong tree with my post. I was in the process of making a composite cable, when my DIN connector broke apart (must be ancient and brittle).
I also tried to make a cable to connect the RGB port to an Apple Color monitor's 15 pin D connector... didn't work. I think the Apple monitor doesn't have the "intensity" line that the C128 requires.
Title: RGBI to Component video on TV?
Post by: Mark Smith on December 30, 2007, 04:57 PM
If you can be a little patient I might get off my arse and finish my RGBI to component converter.

So far I have worked out (but not built):

RGBI to RGB
H-sync + V-Sync to C-Sync

But I need to find a schematic of RGB + C-sync to component ... I've already got a box of tricks that does the job but would like to know how it works to see if an all in one can be done.

Tomorrow is a quiet work day I'll draw it then and someone with a bigger brain than me can criticise it :-)

Mark
Title: RGBI to Component video on TV?
Post by: Mangelore on December 30, 2007, 05:55 PM
Quote from: strandedinnzBut I need to find a schematic of RGB + C-sync to component ... I've already got a box of tricks that does the job but would like to know how it works to see if an all in one can be done.
I have an RGB to component schematic which I'll e-mail to you now.
Title: RGBI to Component video on TV?
Post by: smf on December 31, 2007, 12:37 AM
Quote from: Mangelore
Quote from: strandedinnzBut I need to find a schematic of RGB + C-sync to component ... I've already got a box of tricks that does the job but would like to know how it works to see if an all in one can be done.
I have an RGB to component schematic which I'll e-mail to you now.
How about posting it here?
Title: RGBI to Component video on TV?
Post by: Mangelore on December 31, 2007, 05:51 AM
Quote from: smfHow about posting it here?
Here's a block diagram.
http://us1.webpublications.com.au/static/downloads/articles/102648_RGBVidConverter_Blockdiag.eps

More info here
http://www.siliconchip.com.au/cms/A_102648/printArticle.html

More files here
http://www.siliconchip.com.au/cms/attachments/show.html?year=2004&month=October

I don't have the complete article but you can purchase it online.
Title: RGBI to Component video on TV?
Post by: Mark Smith on December 31, 2007, 12:07 PM
Well I think I've managed to cobble together an RGBI to RGB/SCART converter .. it will need somone to look over it for me, as it's mainly a collate of various bits of the puzzle from sources on the internet, I do need a bit of help manking sure the voltages are correct and in converting volts to smaller volts, and also making sure I've got grounding done right.

Looks OK in my eyes :-)

As soon as I get home I'll upload a picture (work blocks all these picture sharing sites!)

Regards

Mark
Title: RGBI to Component video on TV?
Post by: Mark Smith on December 31, 2007, 12:09 PM
Quote from: Mangelore
Quote from: smfHow about posting it here?
Here's a block diagram.
http://us1.webpublications.com.au/static/downloads/articles/102648_RGBVidConverter_Blockdiag.eps

More info here
http://www.siliconchip.com.au/cms/A_102648/printArticle.html

More files here
http://www.siliconchip.com.au/cms/attachments/show.html?year=2004&month=October

I don't have the complete article but you can purchase it online.
Nice article .. so I purchased it :-)

Mark
Title: RGBI to Component video on TV?
Post by: Mark Smith on December 31, 2007, 05:41 PM
Can some big brains review this for me ?

I'm unsure how to do the voltage conversion stuff (from 12V 600milliamps to 1V and 5V) or how to make it a noise free design .. basically this is a collate of a number of schematics I've found so it's been a learning experience :-)

http://picasaweb.google.com/markinnz/C128Stuff/photo#5150038188089460322

1)  What it's trying to do is convert RGBI to analog RGB
2)  Combine the H-sync + V-Sync in the Green channel (for Sync on Green)
3)  Combine H-Sync + V-Sync into C-Sync (Composite Sync)
4)  Set the SCART to 4:3 aspect ratio
5)  Set the SCART to use RGB input.

Regards

Mark
Title: RGBI to Component video on TV?
Post by: Andrew Sutton on January 01, 2008, 11:38 AM
Would that work for the Component Video (RCA/Phono) connectors on US/NTSC TV? But probably not, the NTSC format is analog, and doesn't the C128 RGBI use digital?
Title: RGBI to Component video on TV?
Post by: Mark Smith on January 01, 2008, 02:41 PM
Quote from: moparramWould that work for the Component Video (RCA/Phono) connectors on US/NTSC TV? But probably not, the NTSC format is analog, and doesn't the C128 RGBI use digital?
Step (6) is to get the RGB to Component :-)

Yes C128 RGBI is digital .. which is what step (1) sorts out by converting it to analog.

Mark
EhPortal 1.34 © 2025, WebDev