2600 color palettes on a 7800?

[SeaGtGruff]

I have a question about the color palettes on the different types of 7800s, specifically when playing 2600 games.

 

I have an NTSC 7800, and I know the color palette in 2600 mode is the same as on an NTSC 2600.

 

I assume that on a PAL 7800, the color palette in 2600 mode is the same as on a PAL 2600-- hues 0, 1, 14, and 15 are gray scale, and the other hues are "scrambled" (or alternating). Is that correct?

 

What about on a "SECAM 7800"? From glancing through some of the threads here, I take it there is no "SECAM 7800" per se, rather it is a "SCART 7800." What is the color palette like on a SCART 7800 in 2600 mode? Is it like the 8-color SECAM palette on a SECAM 2600, or is it different?

 

The reason I ask is because I've started tentatively working on an RPG game engine for the 2600, and I'd like to let the user select the console type on an options menu-- i.e., NTSC 2600, PAL 2600, SECAM 2600, NTSC 7800, PAL 7800, or (I presume) SCART 7800. Among other things, the console type selected would determine the color palette.

 

I'd also like to let the user select the functionality of the console switches-- e.g., "tv type" might be used to select the frame rate or number of scan lines, or it might be used to pause or resume the game, or something else. I know the "tv type" switch is grounded on a SECAM 2600, so it would be hardcoded in the program as "not used" if the "console type" option is set to SECAM 2600. And the 7800's "pause" button is equivalent to the 2600's "tv type" switch, but operates differently (i.e., pressed or not pressed), so that would affect how the program handles it. I presume the "pause" switch on a SCART 7800 functions as it does on an NTSC 7800 or PAL 7800, rather than being grounded. Is that correct?

 

Any answers to these questions would be greatly appreciated!

 

Michael

Edited March 14, 2011 by SeaGtGruff

[Nukey Shay]

Since SCART-equipped 7800's use PAL games, I would imagine that the palette is the same between them. They just look better with the RGB-quality output.

[+Mitch]

Yes, it's just PAL palette but in RGB.

 

Mitch

[SeaGtGruff]

Okay, so if the "console type" is set to "SCART 7800," I can just use the PAL palette. Cool! Although I think it would have been awesome for SCART 7800 owners if a full 128-color palette could have been provided. For that matter, I don't understand why the PAL 2600 couldn't have had more colors, such as

 

PAL Hue 0 = NTSC Hue 0

PAL Hue 2 = NTSC Hue 1

PAL Hue 4 = NTSC Hue 2

PAL Hue 6 = NTSC Hue 3

PAL Hue 8 = NTSC Hue 4

PAL Hue A = NTSC Hue 5

PAL Hue C = NTSC Hue 6

PAL Hue E = NTSC Hue 7

PAL Hue F = NTSC Hue 8

PAL Hue D = NTSC Hue 9

PAL Hue B = NTSC Hue A

PAL Hue 9 = NTSC Hue B

PAL Hue 7 = NTSC Hue C

PAL Hue 5 = NTSC Hue D

PAL Hue 3 = NTSC Hue E

PAL Hue 1 = NTSC Hue F

 

I suppose there must be some technical reason why they didn't do that. Then again, the PAL 8-bit Atari computers have 128 (or 256) colors, *and* the hues don't follow the "scrambled/alternating" scheme used on the PAL 2600, so I presume the reason had more to do with cost than technology.

 

Michael

 

 

 

[Nukey Shay]

It seems as though PAL-compliant circuitry was sort of "hacked into" TIA's design...since it robs from one of the sound channels. The color loss could have stemmed from that?