RGB-VGA Converter -- buy or build?

Jim Leonard trixter at oldskool.org
Sun Mar 14 14:37:26 CDT 2010

As previously discussed in this list, and documented on 
http://www.oldskool.org/pc/cgacal , CGA monitors have circuitry to 
change color index #6 to a different color.  CGA also has a fourth 
"intensity" pin.  Does anyone know if some sort of specially-wired cable 
might be able to convert 4-pin RGBI to something these kinds of 
converters can take as input and everything will still look decently?

I ask because I have a need to do video capture of native CGA output. 
Don't ask :-)

The best solution I've come up with is to use an older VGA card (1990 or 
before) that comes with utilities to force it into CGA emulation -- 
forces 400 scandoubled lines, forces the 8x8 font, and ports react 
properly to MC6845 writes.  This is 95% of the way there, but it's still 
a 70Hz refresh rate, not 60.  All ideas welcome.

On 3/9/2010 11:50 AM, Dan Roganti wrote:
> Jovica Stojoski wrote:
>> Hi,
>> I need scematics of RGB to VGA converter.
> we use one of these, it's almost universal , RGB/CGA/EGA/YUV to VGA
> Converter
> more details on the website
> http://www.jammaboards.com/store/cga/ega/yuv-to-vga-converter-pcb-gbs-8220/prod_291.html
> only $50
> =Dan

Jim Leonard (trixter at oldskool.org)            http://www.oldskool.org/
Help our electronic games project:           http://www.mobygames.com/
Or check out some trippy MindCandy at     http://www.mindcandydvd.com/
A child borne of the home computer wars: http://trixter.wordpress.com/

More information about the cctalk mailing list