1 /*****************************************************************************/
5 /* Internal include file, do not use directly */
7 /* "GTIA, Graphic Television Interface Adaptor, is a custom chip used in the */
8 /* Atari 8-bit family of computers and in the Atari 5200 console. In these */
9 /* systems, GTIA chip works together with ANTIC to produce video display. */
10 /* ANTIC generates the playfield graphics (text and bitmap) while GTIA */
11 /* provides the color for the playfield and adds overlay objects known as */
12 /* player/missile graphics (sprites)" - Wikipedia article on "GTIA" */
15 /* (C) 2000 Freddy Offenga <taf_offenga@yahoo.com> */
16 /* 2019-01-14: Bill Kendrick <nbs@sonic.net>: More defines for registers */
19 /* This software is provided 'as-is', without any expressed or implied */
20 /* warranty. In no event will the authors be held liable for any damages */
21 /* arising from the use of this software. */
23 /* Permission is granted to anyone to use this software for any purpose, */
24 /* including commercial applications, and to alter it and redistribute it */
25 /* freely, subject to the following restrictions: */
27 /* 1. The origin of this software must not be misrepresented; you must not */
28 /* claim that you wrote the original software. If you use this software */
29 /* in a product, an acknowledgment in the product documentation would be */
30 /* appreciated but is not required. */
31 /* 2. Altered source versions must be plainly marked as such, and must not */
32 /* be misrepresented as being the original software. */
33 /* 3. This notice may not be removed or altered from any source */
36 /*****************************************************************************/
42 /* Define a structure with the GTIA register offsets for write (W) */
44 unsigned char hposp0; /* 0x00: horizontal position of player 0 */
45 unsigned char hposp1; /* 0x01: horizontal position of player 1 */
46 unsigned char hposp2; /* 0x02: horizontal position of player 2 */
47 unsigned char hposp3; /* 0x03: horizontal position of player 3 */
48 unsigned char hposm0; /* 0x04: horizontal position of missile 0 */
49 unsigned char hposm1; /* 0x05: horizontal position of missile 1 */
50 unsigned char hposm2; /* 0x06: horizontal position of missile 2 */
51 unsigned char hposm3; /* 0x07: horizontal position of missile 3 */
53 unsigned char sizep0; /* 0x08: size of player 0 */
54 unsigned char sizep1; /* 0x09: size of player 1 */
55 unsigned char sizep2; /* 0x0A: size of player 2 */
56 unsigned char sizep3; /* 0x0B: size of player 3 */
57 unsigned char sizem; /* 0x0C: size of missiles */
59 unsigned char grafp0; /* 0x0D: graphics shape player 0 (used when ANTIC is not instructed to use DMA; see DMACTL) */
60 unsigned char grafp1; /* 0x0E: graphics shape player 1 */
61 unsigned char grafp2; /* 0x0F: graphics shape player 2 */
62 unsigned char grafp3; /* 0x10: graphics shape player 3 */
63 unsigned char grafm; /* 0x11: graphics shape missiles */
65 unsigned char colpm0; /* 0x12: color player and missile 0 */
66 unsigned char colpm1; /* 0x13: color player and missile 1 */
67 unsigned char colpm2; /* 0x14: color player and missile 2 */
68 unsigned char colpm3; /* 0x15: color player and missile 3 */
69 unsigned char colpf0; /* 0x16: color playfield 0 */
70 unsigned char colpf1; /* 0x17: color playfield 1 */
71 unsigned char colpf2; /* 0x18: color playfield 2 */
72 unsigned char colpf3; /* 0x19: color playfield 3 */
73 unsigned char colbk; /* 0x1A: color background */
75 unsigned char prior; /* 0x1B: priority selection */
78 /* 0x1C: vertical delay -- one-line resolution movement of
79 ** vertical position of an object when two line resolution display is enabled
82 unsigned char gractl; /* 0x1D: stick/paddle latch, p/m control */
84 unsigned char hitclr; /* 0x1E: clear p/m collision */
85 unsigned char consol; /* 0x1F: builtin speaker */
89 /* Values for SIZEP0-SIZEP3 and SIZEM registers: */
90 #define PMG_SIZE_NORMAL 0x0 /* one color clock per pixel */
91 #define PMG_SIZE_DOUBLE 0x1 /* two color clocks per pixel */
92 #define PMG_SIZE_QUAD 0x2 /* four color clocks per pixel */
95 /* COLPM0-COLPM3, COLPF0-COLPF3, COLBK color registers:
96 ** See the "HUE_..." #defines in "atari.h" for the hue values;
97 ** Bitwise OR (|) with 0x00 (darkest) through 0x0F (lightest) (only even values are unique)
100 /* PRIOR register values */
102 #define PRIOR_P03_PF03 0x01 /* Players 0-3, then Playfields 0-3, then background */
103 #define PRIOR_P01_PF03_P23 0x02 /* Players 0-1, then Playfields 0-3, then Players 2-3, then background */
104 #define PRIOR_PF03_P03 0x04 /* Playfields 0-3, then Players 0-3, then background */
105 #define PRIOR_PF01_P03_PF23 0x08 /* Playfields 0-1, then Players 0-3, then Playfields 2-3, then background */
107 #define PRIOR_5TH_PLAYER 0x10 /* Four missiles combine to be a 5th player (uses COLPF3) */
109 #define PRIOR_OVERLAP_3RD_COLOR 0x20 /* Overlap of players result in a 3rd color */
110 /* Overlap of players 0 & 1 and of players 2 & 3 results in a third color,
111 ** the logical OR of the two players' colors;
112 ** Other overlaps (e.g., players 0 and 2) result in black (0x00).
115 /* GTIA special graphics mode options */
116 /* Pixels are 2 color clocks wide, and one scanline tall
117 ** (so 80x192 in normal playfield width).
118 ** May be used with both bitmap and character modelines.
121 #define PRIOR_GFX_MODE_9 0x40
122 /* 16 shade shades of the background (COLBK) hue;
123 ** Note: brightnesses other than 0 (darkest) in COLBK cause additional effects
126 #define PRIOR_GFX_MODE_10 0x80
127 /* 9 color palette mode;
128 ** COLPM0 (acts as background) thru COLPM3, followed by COLPF0 thru COLPF3, and COLBK
131 #define PRIOR_GFX_MODE_11 0xC0
132 /* 16 hues of the background (COLBK) brightness;
133 ** Note: hues other than 0 (greys) in COLBK caus additional effects
137 /* VDELAY register values */
139 #define VDELAY_MISSILE0 0x01
140 #define VDELAY_MISSILE1 0x02
141 #define VDELAY_MISSILE2 0x04
142 #define VDELAY_MISSILE3 0x08
143 #define VDELAY_PLAYER0 0x10
144 #define VDELAY_PLAYER1 0x20
145 #define VDELAY_PLAYER2 0x40
146 #define VDELAY_PLAYER3 0x80
149 /* GRACTL register values */
151 #define GRACTL_MISSLES 0x01 /* enable missiles */
152 #define GRACTL_PLAYERS 0x02 /* enable players */
154 #define GRACTL_LATCH_TRIGGER_INPUTS 0x04
155 /* "Latch" triggers; once pressed, will give a continuous
156 ** pressed input until this bit is cleared
160 /* Define a structure with the GTIA register offsets for read (R) */
162 unsigned char m0pf; /* 0x00: missile 0 to playfield collision */
163 unsigned char m1pf; /* 0x01: missile 1 to playfield collision */
164 unsigned char m2pf; /* 0x02: missile 2 to playfield collision */
165 unsigned char m3pf; /* 0x03: missile 3 to playfield collision */
166 unsigned char p0pf; /* 0x04: player 0 to playfield collision */
167 unsigned char p1pf; /* 0x05: player 1 to playfield collision */
168 unsigned char p2pf; /* 0x06: player 2 to playfield collision */
169 unsigned char p3pf; /* 0x07: player 3 to playfield collision */
170 unsigned char m0pl; /* 0x08: missile 0 to player collision */
171 unsigned char m1pl; /* 0x09: missile 1 to player collision */
172 unsigned char m2pl; /* 0x0A: missile 2 to player collision */
173 unsigned char m3pl; /* 0x0B: missile 3 to player collision */
174 unsigned char p0pl; /* 0x0C: player 0 to player collision */
175 unsigned char p1pl; /* 0x0D: player 1 to player collision */
176 unsigned char p2pl; /* 0x0E: player 2 to player collision */
177 unsigned char p3pl; /* 0x0F: player 3 to player collision */
179 unsigned char trig0; /* 0x10: joystick trigger 0 (0=pressed, 1=released) */
180 unsigned char trig1; /* 0x11: joystick trigger 1 */
181 unsigned char trig2; /* 0x12: joystick trigger 2 */
182 unsigned char trig3; /* 0x13: joystick trigger 3 */
184 unsigned char pal; /* 0x14: pal/ntsc flag */
186 unsigned char unused[10];
188 unsigned char consol; /* 0x1F: console buttons */
192 /* PAL register possible values */
194 #define TV_STD_PAL 0x1
195 #define TV_STD_NTSC 0xE
196 /* Note: This only tells you whether the GTIA is PAL or NTSC; some NTSC systems are modded with PAL ANTIC chips; testing VCOUNT limits can be done to check for that */
197 /* Note: Seems like it's not possible to test for SECAM */
200 /* Reading console keys (Start, Select, Option) via CONSOL register: */
202 #define CONSOL_START(x) !((unsigned char)((x) & 1)) /* true if Start pressed */
203 #define CONSOL_SELECT(x) !((unsigned char)((x) & 2)) /* true if Select pressed */
204 #define CONSOL_OPTION(x) !((unsigned char)((x) & 4)) /* true if Option pressed */
208 #endif /* #ifndef __GTIA_H */