mirror of
https://github.com/sehugg/8bitworkshop.git
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60 lines
1.3 KiB
C
60 lines
1.3 KiB
C
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#include "neslib.h"
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#include <string.h>
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#include <stdio.h>
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// VRAM buffer module
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#include "vrambuf.h"
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//#link "vrambuf.c"
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// link the pattern table into CHR ROM
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//#link "chr_generic.s"
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// function to scroll window up and down until end
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void scroll_demo() {
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int x = 0; // x scroll position
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int y = 0; // y scroll position
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int dy = 1; // y scroll direction
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// 32-character array for string-building
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char str[32];
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// clear string array
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memset(str, 0, sizeof(str));
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// infinite loop
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while (1) {
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// write message to string array
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sprintf(str, "%6x %6d", y, y);
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// write string array into VRAM buffer
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putbytes(NTADR_A(2,y%30), str, 32);
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// wait for next frame
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// and flush VRAM buffer
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cflushnow();
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// set scroll (shadow) registers
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scroll(x, y);
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// update y variable
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y += dy;
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// change direction when hitting either edge of scroll area
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if (y >= 479) dy = -1;
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if (y == 0) dy = 1;
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}
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}
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// main function, run after console reset
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void main(void) {
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// set palette colors
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pal_col(1,0x04);
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pal_col(2,0x20);
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pal_col(3,0x30);
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// clear vram buffer
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cclearbuf();
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// set NMI handler
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set_vram_update(updbuf);
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// enable PPU rendering (turn on screen)
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ppu_on_all();
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// scroll window back and forth
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scroll_demo();
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}
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