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View Full Version : Paradise CGA with only one color palette



nestor
June 4th, 2012, 09:34 AM
I have got a Paradise Modular Graphics Card that seems to be damaged, or maybe it was not 100% CGA compatible. In text mode, all 16 colors are showed correctly. But in graphics mode, it always use the same palette (black, white, red and cyan)

Here are some examples:

http://img96.imageshack.us/img96/8571/20120604131427797.th.jpg
Click to enlarge (http://img96.imageshack.us/img96/8571/20120604131427797.jpg)

http://img24.imageshack.us/img24/6425/20120604131443325.th.jpg
Click to enlarge (http://img24.imageshack.us/img24/6425/20120604131443325.jpg)

http://img651.imageshack.us/img651/4026/20120604131553465.th.jpg
Click to enlarge (http://img651.imageshack.us/img651/4026/20120604131553465.jpg)

http://img195.imageshack.us/img195/5350/20120604131919168.th.jpg
Click to enlarge (http://img195.imageshack.us/img195/5350/20120604131919168.jpg)

Any idea if this is the expected behavior?

Stone
June 4th, 2012, 09:53 AM
IIRC, 4 colors is the standard graphics mode for CGA.

Anonymous Freak
June 4th, 2012, 10:49 AM
Yes, but there are multiple palettes available. Magenta/Cyan/White is one, but it should also show Green/Red/Brown (the first photo,) and there is even an unusual Cyan/Red/White, which appears to be what this one is stuck in, showing the third palette in place of the two more common ones.

In fact, doing some reading, it looks like the third palette comes from "disabling the composite color burst bit while in graphics mode." Maybe that's just stuck on your card?

VileR
June 4th, 2012, 04:33 PM
In fact, doing some reading, it looks like the third palette comes from "disabling the composite color burst bit while in graphics mode." Maybe that's just stuck on your card?

looking at TULARC - at least one version of this card has onboard switches to choose between "RGB color", "composite color" and "composite B&W": http://stason.org/TULARC/pc/graphics-cards/U-Z/WESTERN-DIGITAL-CORPORATION-CGA-PARADISE-MODULAR-G.html

Maybe the card is just set to "composite B&W" - this probably force-disables the color burst bit... using RGB output that could produce the cyan/red/white palette as shown.

deathshadow
June 4th, 2012, 06:41 PM
Since you're on a commodore display, can we assume that's a composite connection and not a RGBI? If so, I'd agree with el_VR that it's likely the color burst line is either stuck, or disabled somehow.

Check what that tularc page says -- I'd not be surprised if you're set to either MDA display or Composite B&W, instead of color or color composite.

VileR
June 4th, 2012, 07:39 PM
If it was a composite signal, any output lacking the color-burst would actually show up as grey. My (uneducated) guess is that this is actually RGB(I), the card just needs to be jumpered correctly.

nestor
June 4th, 2012, 11:22 PM
Yes, the display is a Commodore 1084S with RGBI, and the card is jumpered as tularc page says. Maybe that info is not correct, i will try another jumper combinations.
Thanks for the answers!

nestor
June 5th, 2012, 11:45 AM
Mystery solved, jumper P2 must be in 1-2 position (Composite Color). TH99 says that this jumper is N/A when RGB output is used.