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r26436 Wednesday 27th November, 2013 at 19:54:47 UTC by Tafoid
Added Atari 2600, 5200, and 7800 palette notes.  [Robert Tuccitto]
[src/mame/video]tia.c
[src/mess/drivers]a7800.c atari400.c

trunk/src/mess/drivers/atari400.c
r26435r26436
3333    values 24.7 thru 27.7 degrees in 0.5 degree increments.  Enabled
3434    Phase Shift 26.2 degrees as default.
3535
36    NOTE: Atari system's (2600, 5200, 8bit, 7800) palette appear different
37    on modern flat panel displays than their original target display
38    device, CRT.  Most noticeable is Hue 1x which is Gold on a CRT,
39    but appears Green-Yellow on flat panels.  Other hues may be distorted
40    as well on flat panel displays.
36    2013-11-23 Robert Tuccitto:
37   Added palette notes
4138
4239******************************************************************************/
4340
r26435r26436
756753   PORT_BIT(0xff, 0x72, IPT_AD_STICK_Y) PORT_SENSITIVITY(JOYSTICK_SENSITIVITY) PORT_KEYDELTA(JOYSTICK_DELTA) PORT_MINMAX(0x00,0xe4) PORT_PLAYER(4)
757754
758755INPUT_PORTS_END
756/***************************************************************
757Atari 5200 Palette Notes:
759758
759Palette on a modern flat panel display (LCD, LED, Plasma, etc.)
760appears different from a traditional CRT. The most outstanding
761difference is Hue 1x, the hue begin point. Hue 1x looks very
762'green' (~-60 to -45 degrees - depending on how poor or well it
763handles the signal conversion and its calibration) on a modern
764flat panel display, as opposed to 'gold' (~-33 degrees) on a
765CRT.  The official technical document, "GTIA C014805 NTSC"
766stipulates Hue 1x as gold.
760767
768The "Atari 5200 Field Service Manual" provides two different
769sets of instructions in harmony with utilizing the "PAM
770Diagnostic SALT Cartridge v1.1".  In one account it states the
771color just below and above the reference bar to be within one
772shade of each other. 
773
774Under the same reference document, directions are given for it
775to be the same color.  Phase Shift 25.7 degrees matches Hue 1x,
77615x and the color below the reference bar.
777
778However, if the system is adjusted within the first several
779minutes of running, the warm up, consistent system run time,
780causes Hue 15x (F$) to become stronger/darker gold (More brown
781then ultimately red-brown); as well as leans Hue 14x (E$) more
782brown than green.  Once achieving a phase shift of 27.7,
783Hue 14x (E$) and Hue 15x (F$) near-exact match Hue 1x and 2x
784respectively.
785
786Accounting for system 'warm-up', phase shifting, as well as the
787instructions for it to be within one shade of each other, would
788make Phase Shift 26.2 degrees or 26.7 degrees a realistic
789logical choice.
790
791It also collaborates with the official "GTIA C014805 NTSC"
792document for color order: Hue 1x = Gold, Hue 2x = Orange,
793Hue 15x (F$) = Light-Orange; Phase Shift 26.2 places
794Hue 15x (F$) between Hue 1x, Gold and Hue 2x, Orange;
795a Light Orange in color.  Color descriptions are best measured
796in the middle of the brightness scale.
797
798It should be mentioned that Green-Yellow is referenced at
799Hue 13x (D$), nowhere near Hue 1x.  A Green-Yellow Hue 1x is
800how the palette is manipulated and modified (in part) under
801a modern flat panel display.
802
803Note though, even a properly calibrated console, at power on,
804the phase shift appears as low as ~23 degrees and after a
805considerable consistent runtime, can be as high as ~28 degrees. 
806In general, the low end of ~23 degrees lasts for maybe several
807seconds, whereas higher values such as ~25-27 degrees is the
808most dominant during system run time.
809
810Additionally, the blue to red (And consequently blue to green)
811ratio proportions may appear different on a modern flat panel
812display than a CRT in some instances for the Atari 5200 system. 
813Furthermore, you may have some variation of proportions even
814within the same display type.
815 
816One side effect of this on the console's palette is that some
817values of red may appear too pinkish - Too much blue to red. 
818This is not the same as a traditional tint-hue control
819adjustment; rather, can be demonstrated by changing the blue
820ratio values via MESS HLSL settings.
821
822Lastly, the Atari 2600 & 7800 NTSC color palettes hold the same
823hue structure order and have similar appearance differences
824dependent upon display type.
825***************************************************************/
761826/**************************************************************
762827 *
763828 * Palette - Phase Shift 26.2
trunk/src/mess/drivers/a7800.c
r26435r26436
6868
6969    2013/10/27 Robert Tuccitto  Modernized screen parameters for NTSC & PAL.
7070
71    2013/11/03 Fixed correctly typo under 26.7 7$.
71    2013/11/03 Robert Tuccitto Fixed correctly typo under 26.7 7$.
72
73   2014/11/23 Robert Tuccitto Added NTSC Palette Notes
7274***************************************************************************/
7375
7476#include "emu.h"
r26435r26436
98100   AM_RANGE(0x0460, 0x046f) /* XBOARD POKEY2 */
99101   AM_RANGE(0x0470, 0x047f) /* XBOARD CTRL */
100102   AM_RANGE(0x0480, 0x04ff) AM_MIRROR(0x100) AM_RAM    /* RIOT RAM */
101      AM_RANGE(0x1000, 0x17ff) AM_RAM /* hs SRAM */
103   AM_RANGE(0x1000, 0x17ff) AM_RAM /* hs SRAM */
102104   AM_RANGE(0x1800, 0x27ff) AM_RAM
103105   AM_RANGE(0x2800, 0x2fff) AM_RAMBANK("bank7")    /* MAINRAM */
104106   AM_RANGE(0x3000, 0x37ff) AM_RAMBANK("bank7")    /* MAINRAM */
105107   AM_RANGE(0x3800, 0x3fff) AM_RAMBANK("bank7")    /* MAINRAM */
106      AM_RANGE(0x3000, 0x3fff) AM_ROM  /* hs ROM space */
108   AM_RANGE(0x3000, 0x3fff) AM_ROM  /* hs ROM space */
107109   AM_RANGE(0x4000, 0x7fff) AM_ROMBANK("bank1")                        /* f18 hornet */
108110   AM_RANGE(0x4000, 0xffff) AM_WRITE(a7800_cart_w) /* XBOARD SRAM */
109      AM_RANGE(0x8000, 0x9fff) AM_ROMBANK("bank2")                        /* sc */
111   AM_RANGE(0x8000, 0x9fff) AM_ROMBANK("bank2")                        /* sc */
110112   AM_RANGE(0xa000, 0xbfff) AM_ROMBANK("bank3")                        /* sc + ac */
111113   AM_RANGE(0xc000, 0xdfff) AM_ROMBANK("bank4")                        /* ac */
112114   AM_RANGE(0xe000, 0xffff) AM_ROM
r26435r26436
154156   PORT_DIPSETTING(0x00, "B" )
155157INPUT_PORTS_END
156158
159/***************************************************************************
160Atari 7800 NTSC Palette Notes:
157161
162Palette on a modern flat panel display (LCD, LED, Plasma, etc.) appears
163different from a traditional CRT. The most outstanding difference is Hue 1x,
164the hue begin point. Hue 1x looks very 'green' (~-60 to -45 degrees -
165depending on how poor or well it handles the signal conversion and its
166calibration) on a modern flat panel display, as opposed to 'gold' (~-33
167degrees) on a CRT. 
168
169The system's pot adjustment manually manipulates the ratio of blue to
170green/blue to red, while the system 'warming-up' causes the palette phase
171shift to go higher in degrees.
172
173At power on, the system's phase shift appears as low as ~23 degrees and
174after a considerable consistent runtime, can be as high as ~28 degrees.
175 
176In general, the low end of ~23 degrees lasts for maybe several seconds,
177whereas higher values such as ~25-27 degrees is the most dominant during
178system run time.  180 degrees colorburst takes place at ~25.7 degrees (A
179near exact match of Hue 1x and 15x - To the naked eye they appear to be
180the same). 
181 
182However, if the system is adjusted within the first several minutes of
183running, the warm up, consistent system run time, causes Hue 15x (F$) to
184become stronger/darker gold (More brown then ultimately red-brown); as well
185as leans Hue 14x (E$) more brown than green.  Once achieving a phase shift
186of 27.7, Hue 14x (E$) and Hue 15x (F$) near-exact match Hue 1x and 2x
187respectively.
188 
189Therefore, an ideal phase shift while accounting for the reality of
190shifting while warming up, as well as maintaining differences between 1x,
1912x and 14x, 15x, would likely fall between a 25.7 and 27.7. Phase shifts
19226.2 degrees and 26.7 degrees places Hue 15x (F$) between Hue 1x and
193Hue 2x, having 26.2 degrees leaning closer to Hue 1x and 26.7 degrees
194leaning closer to Hue 2x.
195
196The above notion would also harmonize with what has been documented for
197the colors of 1x, 2x, 14x, 15x on the 7800.  1x = Gold, 2x = Orange,
19814x (E$) = Orange-Green. 15x (F$) = Light Orange.  Color descriptions are
199best measured in the middle of the brightness scale.  It should be
200mentioned that Green-Yellow is referenced at Hue 13x (D$), nowhere near
201Hue 1x.  A Green-Yellow Hue 1x is how the palette is manipulated and
202modified (in part) under a modern flat panel display.
203
204Additionally, the blue to red (And consequently blue to green) ratio
205proportions may appear different on a modern flat panel display than a CRT
206in some instances for the Atari 7800 system.  Furthermore, you may have
207some variation of proportions even within the same display type.
208 
209One side effect of this on the console's palette is that some values of
210red may appear too pinkish - Too much blue to red.  This is not the same
211as a traditional tint-hue control adjustment; rather, can be demonstrated
212by changing the blue ratio values via MESS HLSL settings.
213
214Lastly, the Atari 2600 & 5200 NTSC color palettes hold the same hue
215structure order and have similar appearance differences that are dependent
216upon display type.
217***************************************************************************/
158218/***************************************************************************
159219    PALETTE - 26.2 PHASE SHIFT
160220***************************************************************************/
trunk/src/mame/video/tia.c
r26435r26436
4848PALETTE_INIT_MEMBER(tia_ntsc_video_device, tia_ntsc)
4949{
5050   int i, j;
51/********************************
51/********************************************************************
52Atari 2600 NTSC Palette Notes:
53
54Palette on a modern flat panel display (LCD, LED, Plasma, etc.)
55appears different from a traditional CRT. The most outstanding
56difference is Hue 1x, the hue begin point. Hue 1x looks very
57'green' (~-60 to -45 degrees - depending on how poor or well it
58handles the signal conversion and its calibration) on a modern
59flat panel display, as opposed to 'gold' (~-33 degrees) on a CRT.
60
61The official technical documents: "Television Interface Adaptor
62[TIA] (Model 1A)", "Atari VCS POP Field Service Manual", and
63"Stella Programmer's Guide" stipulate Hue 1x to be gold.
64
65The system's pot adjustment manually manipulates the degree of
66phase shift, while the system 'warming-up' will automatically
67push whatever degrees has been manually set, higher.  According
68to the Atari VCS POP Field Service Manual and system diagnostic
69and test (color) cart, instructions are provide to set the pot
70adjustment having Hue 1x and Hue 15x (F$) match or within one
71shade of each other, both a 'goldenrod'.
72
73At power on, the system's phase shift appears as low as ~23
74degrees and after a considerable consistent runtime, can be as
75high as ~28 degrees.
76 
77In general, the low end of ~23 degrees lasts for several seconds,
78whereas higher values such as ~25-27 degrees are the most
79dominant during system run time.  180 degrees colorburst takes
80place at ~25.7 degrees (A near exact match of Hue 1x and 15x -
81To the naked eye they appear to be the same). 
82 
83However, if the system is adjusted within the first several
84minutes of running, the warm up, consistent system run time,
85causes Hue 15x (F$) to become stronger/darker gold (More brown
86then ultimately red-brown); as well as leans Hue 14x (E$) more
87brown than green.  Once achieving a phase shift of 27.7 degrees,
88Hue 14x (E$) and Hue 15x (F$) near-exact match Hue 1x and 2x
89respectively.
90 
91Therefore, an ideal phase shift while accounting for properly
92calibrating a system's color palette within the first several
93minutes of it running via the pot adjustment, the reality of
94shifting while warming up, as well as maintaining differences
95between Hues 1x, 2x and 14x, 15x, would likely fall between 25.7
96and 27.7 degrees.  Phase shifts 26.2 and 26.7 places Hue 15x/F$
97between Hue 1x and Hue 2x, having 26.2 degrees leaning closer to
98Hue 1x and 26.7 degrees leaning closer to Hue 2x.
99 
100The above notion would also harmonize with what has been
101documented within "Stella Programmer's Guide" for the colors of
1021x, 2x, 14x, 15x on the 2600 and 7800.  1x = Gold, 2x = Orange,
10314x (E$) = Orange-Green. 15x (F$) = Light Orange.  Color
104descriptions are best measured in the middle of the brightness
105scale.  It should be mentioned that Green-Yellow is referenced
106at Hue 13x (D$), nowhere near Hue 1x.  A Green-Yellow Hue 1x is
107how the palette is manipulated and modified (in part) under a
108modern flat panel display.
109
110Additionally, the blue to red (And consequently blue to green)
111ratio proportions may appear different on a modern flat panel
112display than a CRT in some instances for the Atari 2600 system. 
113Furthermore, you may have some variation of proportions even
114within the same display type.
115 
116One side effect of this on the console's palette is that some
117values of red may appear too pinkish - Too much blue to red. 
118This is not the same as a traditional tint-hue control adjustment;
119rather, can be demonstrated by changing the blue ratio values
120via MESS HLSL settings.
121
122Lastly, the Atari 5200 & 7800 NTSC color palettes hold the same
123hue structure order and have similar appearance differences that
124are dependent upon display type.
125********************************************************************/
126/*********************************
52127Phase Shift 24.7
53128        {  0.000,  0.000 },
54129        {  0.192, -0.127 },
r26435r26436
156231        {  0.099, -0.182 },
157232        {  0.194, -0.126 },
158233        {  0.244, -0.042 }
159**********************************/
234*********************************/
160235
161236   static const double color[16][2] =
162237/*********************************

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