</descrip><p>
+<sect1>Display lists<p>
+
+An major feature of the Atari graphics chip "ANTIC" is to
+process instructions for the display generation.
+cc65 supports constructing these display lists by offering defines
+for the instructions. In conjunction with the "void"-variable extension
+of cc65, display lists can be created quite comfortable:
+
+<verb>
+...
+unsigned char ScreenMemory[100];
+
+void DisplayList =
+{
+ DL_BLK8,
+ DL_BLK8,
+ DL_BLK8,
+ DL_LMS(DL_CHR20x8x2),
+ ScreenMemory,
+ DL_CHR20x8x2,
+ DL_CHR20x8x2,
+ DL_CHR20x8x2,
+ DL_BLK4,
+ DL_CHR20x8x2,
+ DL_JVB
+};
+...
+POKEW(560,(unsigned int)&DisplayList); // SDLSTL
+...
+</verb>
+
+Please inspect the <tt/_antic.h/ header file to detemine the supported
+instruction names. Modifiers on instructions can be nested without need
+for an order:
+
+<tt/DL_LMS(DL_HSCROL(DL_VSCROL(DL_DLI(DL_MAP80x4x2))))/
+
+Please mind that ANTIC has memory alignment requirements for "player
+missile graphics"-data, font data, display lists and screen memory. Creation
+of a special linker configuration with appropriate aligned segments and
+switching to that segment in the c-code is usually neccessary. A more memory
+hungry solution consists in using the "<tt/posix_memalign()/" function in
+conjunction with copying your data to the allocated memory.
<sect1>Character mapping<p>
/* antic instruction set */
/* absolute instructions (non mode lines) */
-#define DL_JMP 1
-#define DL_JVB 65
+#define DL_JMP (unsigned char) 1
+#define DL_JVB (unsigned char) 65
-#define DL_BLK1 0
-#define DL_BLK2 16
-#define DL_BLK3 32
-#define DL_BLK4 48
-#define DL_BLK5 64
-#define DL_BLK6 80
-#define DL_BLK7 96
-#define DL_BLK8 112
+#define DL_BLK1 (unsigned char) 0
+#define DL_BLK2 (unsigned char) 16
+#define DL_BLK3 (unsigned char) 32
+#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) */
-#define DL_CHR40x8x1 2 /* monochrome, 40 character & 8 scanlines per mode line (GR. 0) */
-#define DL_CHR40x10x1 3 /* monochrome, 40 character & 10 scanlines per mode line */
-#define DL_CHR40x8x4 4 /* colour, 40 character & 8 scanlines per mode line (GR. 12) */
-#define DL_CHR40x16x4 5 /* colour, 40 character & 16 scanlines per mode line (GR. 13) */
-#define DL_CHR20x8x2 6 /* colour (duochrome per character), 20 character & 8 scanlines per mode line (GR. 1) */
-#define DL_CHR20x16x2 7 /* colour (duochrome per character), 20 character & 16 scanlines per mode line (GR. 2) */
+#define DL_CHR40x8x1 (unsigned char) 2 /* monochrome, 40 character & 8 scanlines per mode line (GR. 0) */
+#define DL_CHR40x10x1 (unsigned char) 3 /* monochrome, 40 character & 10 scanlines per mode line */
+#define DL_CHR40x8x4 (unsigned char) 4 /* colour, 40 character & 8 scanlines per mode line (GR. 12) */
+#define DL_CHR40x16x4 (unsigned char) 5 /* colour, 40 character & 16 scanlines per mode line (GR. 13) */
+#define DL_CHR20x8x2 (unsigned char) 6 /* colour (duochrome per character), 20 character & 8 scanlines per mode line (GR. 1) */
+#define DL_CHR20x16x2 (unsigned char) 7 /* colour (duochrome per character), 20 character & 16 scanlines per mode line (GR. 2) */
-#define DL_MAP40x8x4 8 /* colour, 40 pixel & 8 scanlines per mode line (GR. 3) */
-#define DL_MAP80x4x2 9 /* 'duochrome', 80 pixel & 4 scanlines per mode line (GR.4) */
-#define DL_MAP80x4x4 10 /* colour, 80 pixel & 4 scanlines per mode line (GR.5) */
-#define DL_MAP160x2x2 11 /* 'duochrome', 160 pixel & 2 scanlines per mode line (GR.6) */
-#define DL_MAP160x1x2 12 /* 'duochrome', 160 pixel & 1 scanline per mode line (GR.14) */
-#define DL_MAP160x2x4 13 /* 4 colours, 160 pixel & 2 scanlines per mode line (GR.7) */
-#define DL_MAP160x1x4 14 /* 4 colours, 160 pixel & 1 scanline per mode line (GR.15) */
-#define DL_MAP320x1x1 15 /* monochrome, 320 pixel & 1 scanline per mode line (GR.8) */
+#define DL_MAP40x8x4 (unsigned char) 8 /* colour, 40 pixel & 8 scanlines per mode line (GR. 3) */
+#define DL_MAP80x4x2 (unsigned char) 9 /* 'duochrome', 80 pixel & 4 scanlines per mode line (GR.4) */
+#define DL_MAP80x4x4 (unsigned char) 10 /* colour, 80 pixel & 4 scanlines per mode line (GR.5) */
+#define DL_MAP160x2x2 (unsigned char) 11 /* 'duochrome', 160 pixel & 2 scanlines per mode line (GR.6) */
+#define DL_MAP160x1x2 (unsigned char) 12 /* 'duochrome', 160 pixel & 1 scanline per mode line (GR.14) */
+#define DL_MAP160x2x4 (unsigned char) 13 /* 4 colours, 160 pixel & 2 scanlines per mode line (GR.7) */
+#define DL_MAP160x1x4 (unsigned char) 14 /* 4 colours, 160 pixel & 1 scanline per mode line (GR.15) */
+#define DL_MAP320x1x1 (unsigned char) 15 /* monochrome, 320 pixel & 1 scanline per mode line (GR.8) */
/* modifiers on mode lines */
-#define DL_HSCROL 16
-#define DL_VSCROL 32
-#define DL_LMS 64
+#define DL_HSCROL(x) (unsigned char)((x) | 16)
+#define DL_VSCROL(x) (unsigned char)((x) | 32)
+#define DL_LMS(x) (unsigned char)((x) | 64)
/* general modifier */
-#define DL_DLI 128
+#define DL_DLI(x) (unsigned char)((x) | 128)
/* End of _antic.h */
#endif /* #ifndef __ANTIC_H */
--- /dev/null
+/*
+** testprogram for ANTIC instructions as defined in "_antic.h"
+**
+** 23-Feb-2017, Christian Krueger
+*/
+
+#include <conio.h>
+#include <atari.h>
+#include <peekpoke.h>
+#include <string.h>
+
+// code is only for testing purposes, as screen and display list are not aligned
+// and jumps not set!
+
+unsigned char DummyScreen[400];
+
+void DisplayList = {
+ DL_BLK1,
+ DL_BLK2,
+ DL_BLK3,
+ DL_BLK4,
+ DL_BLK5,
+ DL_BLK6,
+ DL_BLK7,
+ DL_DLI(DL_BLK8),
+ DL_LMS(DL_CHR40x8x1),
+ DummyScreen,
+ DL_HSCROL(DL_CHR40x10x1),
+ DL_VSCROL(DL_CHR40x8x4),
+ DL_CHR40x16x4,
+ DL_LMS(DL_HSCROL(DL_VSCROL(DL_DLI(DL_CHR20x8x2)))),
+ DummyScreen+120,
+ DL_CHR20x16x2,
+ DL_MAP40x8x4,
+ DL_MAP80x4x2,
+ DL_MAP80x4x4,
+ DL_MAP160x2x2,
+ DL_MAP160x1x2,
+ DL_MAP160x2x4,
+ DL_MAP160x1x4,
+ DL_MAP320x1x1,
+ DL_JVB,
+ DL_JMP
+};
+
+unsigned char dlend = 0;
+
+
+int
+main(void)
+{
+ // unfortunately "sizeof()" doesn't work with void data
+ // (Error: Size of data type is unknown)
+ // so we trick with the adresses at front and behind...
+
+ int returnValue = (((unsigned int)&dlend-(unsigned int)&DisplayList) != 28); // assure only one byte per instruction!
+
+ clrscr();
+ if (returnValue)
+ cputs("Test FAILED!");
+ else
+ cputs("Test passed.");
+
+ cputs("\n\rHit any key to exit...");
+ cgetc();
+
+ return returnValue;
+}
+