// Atari 8-bit ANTIC hardware #if not(ATARI_8) #warn a8_antic module should be used only on Atari computer-compatible targets #endif // ANTIC Display List Instruction Set // THE DISPLAY LIST CANNOT CROSS A 1K BYTE MEMORY BOUNDARY UNLESS A JUMP INSTRUCTION IS USED! const byte LMS = $40 // Load memory scan 10-bit counter, $fff boundary. const byte DLI = $80 // Display list interrupt - Interrupt CPU at beginning of last scan line. const byte HSCROL = $10 // Enable horizontal scrolling. const byte VSCROL = $20 // Enable vertical scrolling. const byte JMP = 1 // Jump command - followed by two bytes indicating the new instruction pointer for the display list. const byte JVB = $41 // Jump and wait for Vertical Blank - suspends the display list until vertical blank and then jumps. //+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ //+ BASIC + colors + resolution + display mode + scan lines per row + screen memory + bytes per line + bits per pixel + const byte MODE_2 = 2 //+ 0 + 2 + 40x24 + text + 8 + 960 B + 40 + 8 + const byte MODE_3 = 3 //+ - + 2 + 40x24 + text + 10 + 760 B + 40 + 8 + const byte MODE_4 = 4 //+ 12 + 5 + 40x24 + text + 8 + 960 B + 40 + 8 + const byte MODE_5 = 5 //+ 13 + 5 + 40x12 + text + 16 + 480 B + 40 + 8 + const byte MODE_6 = 6 //+ 1 + 5 + 20x24 + text + 8 + 480 B + 20 + 8 + const byte MODE_7 = 7 //+ 2 + 5 + 20x12 + text + 16 + 240 B + 20 + 8 + const byte MODE_8 = 8 //+ 3 + 4 + 40x24 + graphics + 8 + 240 B + 10 + 2 + const byte MODE_9 = 9 //+ 4 + 2 + 80x48 + graphics + 4 + 480 B + 10 + 1 + const byte MODE_A = $a //+ 5 + 4 + 80x48 + graphics + 4 + 960 B + 20 + 2 + const byte MODE_B = $b //+ 6 + 2 + 160x96 + graphics + 2 + 1920 B + 20 + 1 + const byte MODE_C = $c //+ 14 + 2 + 160x192 + graphics + 1 + 3840 B + 20 + 1 + const byte MODE_D = $d //+ 7 + 4 + 160x96 + graphics + 2 + 3840 B + 40 + 2 + const byte MODE_E = $e //+ 15 + 4 + 160x192 + graphics + 1 + 7680 B + 40 + 2 + const byte MODE_F = $f //+8,9,10,11+ 2 + 320x192 + graphics + 1 + 7680 B + 40 + 1 + //+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ const byte BLANK_1 = 0 const byte BLANK_2 = $10 const byte BLANK_3 = $20 const byte BLANK_4 = $30 const byte BLANK_5 = $40 const byte BLANK_6 = $50 const byte BLANK_7 = $60 const byte BLANK_8 = $70 //+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ volatile byte antic_dmactl @$D400 // direct memory access control volatile byte antic_chactl @$D401 // character mode control volatile word antic_dlist @$D402 // display list pointer volatile byte antic_dlistl @$D402 // display list pointer low-byte volatile byte antic_dlisth @$D403 // display list pointer high-byte volatile byte antic_hscrol @$D404 // horizontal scroll enable volatile byte antic_vscrol @$D405 // vertical scroll enable volatile byte antic_unuse0 @$D406 // unused volatile byte antic_pmbase @$D407 // msb of p/m base address volatile byte antic_unuse1 @$D408 // unused volatile byte antic_chbase @$D409 // character base address volatile byte antic_wsync @$D40A // wait for horizontal synchronization volatile byte antic_vcount @$D40B // vertical line counter volatile byte antic_penh @$D40C // light pen horizontal position volatile byte antic_penv @$D40D // light pen vertical position volatile byte antic_nmien @$D40E // non-maskable interrupt enable volatile byte antic_nmist @$D40F // (R) NMI status; holds cause for the NMI interrupt, corresponding to the same bits in NMIEN volatile byte antic_nmires @$D40F // (W) Reset for NMIST; clears the interrupt request register