/*****************************************************************************/ /* */ /* _antic.h */ /* */ /* Internal include file, do not use directly */ /* */ /* */ /* "ANTIC, Alphanumeric Television Interface Controller, is responsible for */ /* the generation of playfield graphics which is delivered as a datastream */ /* to the related CTIA/GTIA chip. The CTIA/GTIA provides the coloring of the */ /* playfield graphics, and is responsible for adding overlaid sprite */ /* (referred to as "Player/Missile graphics" by Atari). Atari advertised it */ /* as a true microprocessor, in that it has an instruction set to run */ /* programs (called display lists) to process data. ANTIC has no capacity */ /* for writing back computed values to memory, it merely reads data from */ /* memory and processes it for output to the screen, therefore it is not */ /* Turing complete." - Wikipedia article on "ANTIC" (with edits) */ /* */ /* (C) 2000 Freddy Offenga */ /* 24-Jan-2011: Christian Krueger: Added defines for Antic instruction set */ /* 2019-01-16: Bill Kendrick : More defines for registers */ /* */ /* */ /* This software is provided 'as-is', without any expressed or implied */ /* warranty. In no event will the authors be held liable for any damages */ /* arising from the use of this software. */ /* */ /* Permission is granted to anyone to use this software for any purpose, */ /* including commercial applications, and to alter it and redistribute it */ /* freely, subject to the following restrictions: */ /* */ /* 1. The origin of this software must not be misrepresented; you must not */ /* claim that you wrote the original software. If you use this software */ /* in a product, an acknowledgment in the product documentation would be */ /* appreciated but is not required. */ /* 2. Altered source versions must be plainly marked as such, and must not */ /* be misrepresented as being the original software. */ /* 3. This notice may not be removed or altered from any source */ /* distribution. */ /* */ /*****************************************************************************/ #ifndef __ANTIC_H #define __ANTIC_H /*****************************************************************************/ /* Define a structure with the ANTIC coprocessor's register offsets */ /*****************************************************************************/ struct __antic { unsigned char dmactl; /* (W) direct memory access control */ unsigned char chactl; /* (W) character mode control */ unsigned char dlistl; /* display list pointer low-byte */ unsigned char dlisth; /* display list pointer high-byte */ unsigned char hscrol; /* (W) horizontal scroll enable */ unsigned char vscrol; /* (W) vertical scroll enable */ unsigned char unuse0; /* unused */ unsigned char pmbase; /* (W) msb of p/m base address (for when DMACTL has player and/or missile DMA enabled) */ unsigned char unuse1; /* unused */ unsigned char chbase; /* (W) msb of character set base address */ unsigned char wsync; /* (W) wait for horizontal synchronization */ unsigned char vcount; /* (R) vertical line counter */ unsigned char penh; /* (R) light pen horizontal position */ unsigned char penv; /* (R) light pen vertical position */ unsigned char nmien; /* (W) non-maskable interrupt enable */ union { /* (W) ("NMIRES") nmi reset -- clears the interrupt request register; ** resets all of the NMI status together */ unsigned char nmires; /* (R) ("NMIST") nmi status -- holds cause for the NMI interrupt */ unsigned char nmist; }; }; /*****************************************************************************/ /* DMACTL register options */ /*****************************************************************************/ /* Initialized to 0x22: DMA fetch, normal playfield, no PMG DMA, double-line PMGs */ /* Playfield modes: */ #define DMACTL_PLAYFIELD_NONE 0x00 #define DMACTL_PLAYFIELD_NARROW 0x01 /* e.g., 32 bytes per scanline with thick borders */ #define DMACTL_PLAYFIELD_NORMAL 0x02 /* e.g., 40 bytes per scanline with normal borders */ #define DMACTL_PLAYFIELD_WIDE 0x03 /* e.g., 48 bytes per scanline with no borders (overscan) */ /* Other options: */ /* If not set, GTIA's GRAFP0 thru GRAFP3, and/or GRAFM registers are used for ** player & missile shapes, respectively. (Modify the registers during the horizontal blank ** (Display List Interrupt), a la "racing the beam" on an Atari VCS/2600, ) ** if set, ANTIC's PMBASE will be used to fetch shapes from memory via DMA. */ #define DMACTL_DMA_MISSILES 0x04 #define DMACTL_DMA_PLAYERS 0x08 /* Unless set, PMGs (as fetched via DMA) will be double-scanline resolution */ #define DMACTL_PMG_SINGLELINE 0x10 /* Unless set, ANTIC operation is disabled, since it cannot fetch ** Display List instructions */ #define DMACTL_DMA_FETCH 0x20 /*****************************************************************************/ /* CHACTL register options */ /*****************************************************************************/ /* Initialized to 2 (CHACTL_CHAR_NORMAL | CHACTL_INV_PRESENT) */ /* Inverted (upside-down) characters */ #define CHACTL_CHAR_NORMAL 0x00 #define CHACTL_CHAR_INVERTED 0x04 /* Inverse (reverse-video) characters */ #define CHACTL_INV_TRANS 0x00 /* chars with high-bit shown */ #define CHACTL_INV_OPAQUE 0x01 /* chars with high-bit appear as space */ #define CHACTL_INV_PRESENT 0x02 /* chars with high-bit are reverse-video */ /*****************************************************************************/ /* Values for NMIEN (enabling interrupts) & NMIST (cause for the interrupt) */ /*****************************************************************************/ /* Display List Interrupts ** Called on a modeline when "DL_DLI" bit is set the ANTIC instruction, ** and jumps through VDSLST vector. */ #define NMIEN_DLI 0x80 /* Vertical Blank Interrupt ** Called during every vertical blank; see SYSVBV, VVBLKI, CRITIC, and VVBLKD, ** as well as the SETVBV routine. */ #define NMIEN_VBI 0x40 /* [Reset] key pressed */ #define NMIEN_RESET 0x20 /*****************************************************************************/ /* ANTIC instruction set */ /*****************************************************************************/ /* Absolute instructions (non mode lines) */ #define DL_JMP ((unsigned char) 1) #define DL_JVB ((unsigned char) 65) #define DL_BLK1 ((unsigned char) 0) /* 1 blank scanline */ #define DL_BLK2 ((unsigned char) 16) /* 2 blank scanlines */ #define DL_BLK3 ((unsigned char) 32) /* ...etc. */ #define DL_BLK4 ((unsigned char) 48) #define DL_BLK5 ((unsigned char) 64) #define DL_BLK6 ((unsigned char) 80) #define DL_BLK7 ((unsigned char) 96) #define DL_BLK8 ((unsigned char) 112) /* Absolute instructions (mode lines) */ /* Note: Actual width varies (e.g., 40 vs 32 vs 48) depending on ** normal vs narrow vs wide (overscan) playfield setting; see DMACTL */ /* Character modes (text, tile graphics, etc.) */ /* monochrome, 40 character & 8 scanlines per mode line (aka Atari BASIC GRAPHICS 0 via OS's CIO routines) */ #define DL_CHR40x8x1 ((unsigned char) 2) /* monochrome, 40 character & 10 scanlines per mode line (like GR. 0, with descenders) */ #define DL_CHR40x10x1 ((unsigned char) 3) /* colour, 40 character & 8 scanlines per mode line (GR. 12) */ #define DL_CHR40x8x4 ((unsigned char) 4) /* colour, 40 character & 16 scanlines per mode line (GR. 13) */ #define DL_CHR40x16x4 ((unsigned char) 5) /* colour (duochrome per character), 20 character & 8 scanlines per mode line (GR. 1) */ #define DL_CHR20x8x2 ((unsigned char) 6) /* colour (duochrome per character), 20 character & 16 scanlines per mode line (GR. 2) */ #define DL_CHR20x16x2 ((unsigned char) 7) /* Bitmap modes */ /* colour, 40 pixel & 8 scanlines per mode line (GR. 3) */ #define DL_MAP40x8x4 ((unsigned char) 8) /* 'duochrome', 80 pixel & 4 scanlines per mode line (GR.4) */ #define DL_MAP80x4x2 ((unsigned char) 9) /* colour, 80 pixel & 4 scanlines per mode line (GR.5) */ #define DL_MAP80x4x4 ((unsigned char) 10) /* 'duochrome', 160 pixel & 2 scanlines per mode line (GR.6) */ #define DL_MAP160x2x2 ((unsigned char) 11) /* 'duochrome', 160 pixel & 1 scanline per mode line (GR.14) */ #define DL_MAP160x1x2 ((unsigned char) 12) /* 4 colours, 160 pixel & 2 scanlines per mode line (GR.7) */ #define DL_MAP160x2x4 ((unsigned char) 13) /* 4 colours, 160 pixel & 1 scanline per mode line (GR.15) */ #define DL_MAP160x1x4 ((unsigned char) 14) /* monochrome, 320 pixel & 1 scanline per mode line (GR.8) */ #define DL_MAP320x1x1 ((unsigned char) 15) /* Equivalents, for people familiar with Atari 8-bit OS */ #define DL_GRAPHICS0 DL_CHR40x8x1 #define DL_GRAPHICS1 DL_CHR20x8x2 #define DL_GRAPHICS2 DL_CHR20x16x2 #define DL_GRAPHICS3 DL_MAP40x8x4 #define DL_GRAPHICS4 DL_MAP80x4x2 #define DL_GRAPHICS5 DL_MAP80x4x4 #define DL_GRAPHICS6 DL_MAP160x2x2 #define DL_GRAPHICS7 DL_MAP160x2x4 #define DL_GRAPHICS8 DL_MAP320x1x1 #define DL_GRAPHICS9 DL_MAP320x1x1 /* N.B.: GRAPHICS 9, 10, and 11 also involve GTIA's PRIOR register */ #define DL_GRAPHICS10 DL_MAP320x1x1 #define DL_GRAPHICS11 DL_MAP320x1x1 #define DL_GRAPHICS12 DL_CHR40x8x4 /* N.B.: Atari 400/800 OS didn't have GRAPHICS 12 or 13 */ #define DL_GRAPHICS13 DL_CHR40x16x4 #define DL_GRAPHICS14 DL_MAP160x1x2 #define DL_GRAPHICS15 DL_MAP160x1x4 /* Atari 400/800 OS didn't have GRAPHICS 14 or 15, so they were known by "6+" and "7+" */ #define DL_GRAPHICS6PLUS DL_GRAPHICS14 #define DL_GRAPHICS7PLUS DL_GRAPHICS15 /* Neither Atari 400/800 nor XL OS supported 10-scanline (descenders) text mode via CIO */ #define DL_GRAPHICS0_DESCENDERS DL_CHR40x10x1 /* Modifiers to mode lines */ #define DL_HSCROL(x) ((unsigned char)((x) | 16)) /* enable smooth horizontal scrolling on this line; see HSCROL */ #define DL_VSCROL(x) ((unsigned char)((x) | 32)) /* enable smooth vertical scrolling on this line; see VSCROL */ #define DL_LMS(x) ((unsigned char)((x) | 64)) /* Load Memory Scan (next two bytes must be the LSB/MSB of the data to load) */ /* General modifier */ #define DL_DLI(x) ((unsigned char)((x) | 128)) /* enable Display List Interrupt on this mode line */ /* End of _antic.h */ #endif /* #ifndef __ANTIC_H */