zacharyfruhling Posted May 25, 2015 Share Posted May 25, 2015 Does anyone happen to have the precise RGB color codes for the standard TI-99/4A color palette? I am trying my hand at porting some of my old programs and want to keep a similar aesthetic. TI Color Codes: 2 - Black 3 - Medium Green 4 - Light Green 5 - Dark Blue 6 - Light Blue 7 - Dark Red 8 - Cyan 9 - Medium Red 10 - Light Red 11 - Dark Yellow 12 - Light Yellow 13 - Dark Green 14 - Magenta 15 - Gray 16 - White RGB Equivalents? ... Thanks! Zachary 1 Quote Link to comment Share on other sites More sharing options...
zacharyfruhling Posted May 25, 2015 Author Share Posted May 25, 2015 I found some RGB color codes listed at this link, but they don't look quite right to me: http://briantw.com/ti-99/4a/TI%20RGB%20Values.Txt Does anyone know the RGB or hex codes used for the TI colors in the Classic99 emulator? Quote Link to comment Share on other sites More sharing options...
Tursi Posted May 25, 2015 Share Posted May 25, 2015 I don't have the source with me at the moment, but Classic99's open source, you can download it and look in tivdp.cpp for the palette. I actually have a half dozen palettes in there (if I didn't remove the extras ). I (and numerous others, even on this forum) have attacked the question of the 9918 color numerous times. I went so far as to hire an artist to attempt to color match for me. The ultimate problem, though, is there really isn't an RGB equivalent. Let me explain why. We pretty much all start with the datasheet, which lists the approximate values for YCrCb, which is (as I follow) how the color is first generated inside the chip. From the patent and from discussions with the creator, we know that these values are literally taps along a resistor line, and the stated word is that the datasheet isn't necessarily perfect. Still, it's a good starting point - but it's analog, right there on the chip, and therefore subject to variances. After that, we come out to the video circuitry. There are two types of NTSC compatible 9918 - the composite video version used in the TI-99/4 series, and the component version used in the ColecoVision (each machine is just an example). These signals are run out through video mixing/amplification circuitry, as necessary, which shifts the signals some. Ultimately, you end up at a monitor, probably as composite video (meaning you've now lost some bandwidth -- actually on the 9918 you've lost that bandwidth before it even reaches the output pin). Now you run into a monitor's decode circuitry, where the actual color displayed depends on the alignment of the monitor's clocks with the input signal. On original monitors, where 'hue' was an adjustment control, that could literally be anything. Modern displays remove a lot of the control, so I suppose are at least more consistent. At any rate, we can be as true as we want to the datasheet, but the actual color displayed depends on a lot more than that internal tap. So my stance is that the best we can do it get it pretty close to an average sample, and be happy. 3 Quote Link to comment Share on other sites More sharing options...
sometimes99er Posted May 25, 2015 Share Posted May 25, 2015 These are from MESS. 0x000000, // 1 black 0x21c842, // 2 green 0x5edc78, // 3 light green 0x5455ed, // 4 blue 0x7d76fc, // 5 light blue 0xd4524d, // 6 dark red 0x42ebf5, // 7 cyan 0xfc5554, // 8 red 0xff7978, // 9 light red 0xd4c154, // 10 dark yellow 0xe6ce80, // 11 light yellow 0x21b03b, // 12 dark green 0xc95bba, // 13 magenta 0xcccccc, // 14 gray 0xffffff // 15 white 2 Quote Link to comment Share on other sites More sharing options...
+acadiel Posted May 26, 2015 Share Posted May 26, 2015 Yep, you also have to add the fact that some people are used to watching on a television set with their /4A (and you get funky artifacts, and strangely off colors by design), and some are more in tune with a RGB monitor (i.e. Geneve). The first time I looked at a Geneve hooked up via RGB and compared it to my /4A, I noticed a huge difference in some programs. So, you have the following: 1) Technically correct (via data sheet) 2) Correct as seen via a RF modulator on an 80's television (what people were used to) 3) Correct as seen through a composite connection on a composite monitor (shouldn't be much different than #2, but including for completeness) 4) Correct as seen through a RGB connection (EVPC, Geneve, or other 9938/9958 type of connection) 5) Correct as seen via a VGA monitor (F18A) 6) Correct as seen via emulation (Classic 99, MESS, and even these can be different because of what the author used). Quote Link to comment Share on other sites More sharing options...
artrag Posted May 26, 2015 Share Posted May 26, 2015 have a look at the sources of openmsx you can find them here http://openmsx.sourceforge.net/ Quote Link to comment Share on other sites More sharing options...
matthew180 Posted May 26, 2015 Share Posted May 26, 2015 The F18A uses these for the 12-bit (4-bits per color) approximations: -- Palette 0, original 9918A NTSC color approximations x"000", -- 0 Transparent x"000", -- 1 Black x"2C3", -- 2 Medium Green x"5D6", -- 3 Light Green x"54F", -- 4 Dark Blue x"76F", -- 5 Light Blue x"D54", -- 6 Dark Red x"4EF", -- 7 Cyan x"F54", -- 8 Medium Red x"F76", -- 9 Light Red x"DC3", -- 10 Dark Yellow x"ED6", -- 11 Light Yellow x"2B2", -- 12 Dark Green x"C5C", -- 13 Magenta x"CCC", -- 14 Gray x"FFF", -- 15 White These values were generated from the color data on pg. 2-17 (26 in the PDF) of the 9918A datasheet. 1 Quote Link to comment Share on other sites More sharing options...
ColecoFan1981 Posted March 10, 2016 Share Posted March 10, 2016 (edited) The F18A uses these for the 12-bit (4-bits per color) approximations: -- Palette 0, original 9918A NTSC color approximations x"000", -- 0 Transparent x"000", -- 1 Black x"2C3", -- 2 Medium Green x"5D6", -- 3 Light Green x"54F", -- 4 Dark Blue x"76F", -- 5 Light Blue x"D54", -- 6 Dark Red x"4EF", -- 7 Cyan x"F54", -- 8 Medium Red x"F76", -- 9 Light Red x"DC3", -- 10 Dark Yellow x"ED6", -- 11 Light Yellow x"2B2", -- 12 Dark Green x"C5C", -- 13 Magenta x"CCC", -- 14 Gray x"FFF", -- 15 White These values were generated from the color data on pg. 2-17 (26 in the PDF) of the 9918A datasheet. Matthew, I am sorry for not responding to this thread when it was active, but I could suggest these values for future MESS and Classic99 emulation: 1 - Black (#000000) 2 - Medium Green (#46B83C) 3 - Light Green (#7CCF70) 4 - Dark Blue (#5D4DFF) 5 - Light Blue (#7F71FF) 6 - Dark Red (#B66247) 7 - Cyan (#5CC7EE) 8 - Medium Red (#D86B48) 9 - Light Red (#FB8F6C) 10 (A) - Dark Yellow (#C3CE42) 11 (B) - Light Yellow (#D3DB77) 12 (C ) - Dark Green (#3EA030) 13 (D) - Magenta (#B664C6) 14 (E) - Gray (#CDCDCD) 15 (F) - White (#FFFFFF) The TMS9928A colors are as follows (0.47 saturation level) 1 - Black (#000000) 2 - Medium Green (#44B54E) 3 - Light Green (#79CEEA) 4 - Dark Blue (#5B56D7) 5 - Light Blue (#8178EA) 6 - Dark Red (#B56054) 7 - Cyan (#6CDAEC) 8 - Medium Red (#D5685D) 9 - Light Red (#F98C81) 10 (A) - Dark Yellow (#CCC366) 11 (B) - Light Yellow (#DED18D) 12 (C ) - Dark Green (#3F9F45) 13 (D) - Magenta (#B469B2) 14 (E) - Gray (#CDCDCD) 15 (F) - White (#FFFFFF) ~Ben Edited March 10, 2016 by ColecoFan1981 Quote Link to comment Share on other sites More sharing options...
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