mirror of
https://github.com/sehugg/8bitworkshop.git
synced 2024-11-27 01:51:35 +00:00
51 lines
1.1 KiB
C
51 lines
1.1 KiB
C
|
|
||
|
|
//#resource "astrocade.inc"
|
||
|
|
#include "aclib.h"
|
||
|
|
//#link "aclib.s"
|
||
|
|
#include "acbios.h"
|
||
|
|
//#link "acbios.s"
|
||
|
|
//#link "hdr_autostart.s"
|
||
|
|
|
||
|
|
#include <stdlib.h>
|
||
|
|
#include <string.h>
|
||
|
|
|
||
|
|
#pragma opt_code_speed
|
||
|
|
|
||
|
|
// we have a special interrupt handler that sets
|
||
|
|
// palette colors every 4 lines
|
||
|
|
byte linenum = 0;
|
||
|
|
|
||
|
|
void inthandler(void) __interrupt {
|
||
|
|
byte i = linenum;
|
||
|
|
hw_col0l = i;
|
||
|
|
hw_col1l = i+1;
|
||
|
|
hw_col2l = i+2;
|
||
|
|
hw_col3l = i+3;
|
||
|
|
i += 4;
|
||
|
|
if (i > 200) i = 0;
|
||
|
|
hw_inlin = i;
|
||
|
|
linenum = i;
|
||
|
|
}
|
||
|
|
|
||
|
|
// pointer to the interrupt handler
|
||
|
|
const t_interrupt_handler const intvector = &inthandler;
|
||
|
|
|
||
|
|
// patterns to fill each 4-line scanline group
|
||
|
|
const byte FILLPATS[4] = { 0x00, 0x55, 0xaa, 0xff };
|
||
|
|
|
||
|
|
void main(void) {
|
||
|
|
// fill screen with colors 0-3 every 4 scanlines
|
||
|
|
for (byte i=0; i<89; i++) {
|
||
|
|
memset(&vidmem[i], FILLPATS[i&3], 40);
|
||
|
|
}
|
||
|
|
// set our custom interrupt vector
|
||
|
|
set_interrupt_vector(&intvector);
|
||
|
|
// set screen height
|
||
|
|
// set horizontal color split (position / 4)
|
||
|
|
// set interrupt status (on)
|
||
|
|
SYS_SETOUT(89*2, 20, 0x8);
|
||
|
|
// infinite loop
|
||
|
|
// let the interrupt handler do the work
|
||
|
|
while (1) ;
|
||
|
|
}
|