49 lines
1.0 KiB
C
49 lines
1.0 KiB
C
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#include <nes.h>
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const unsigned char TEXT[]="Hello PPU!!!!";
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const unsigned char PALETTE[]={0x1, 0x00, 0x10, 0x20}; // blue, gray, lt gray, white
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void main (void) {
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unsigned char index; // used in 'for' loops
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// if we've just powered on,
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// wait for PPU to warm-up
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waitvblank();
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waitvblank();
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// turn off screen
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PPU.control = 0x0; // NMI off
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PPU.mask = 0x0; // screen off
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// load the palette
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// set PPU address to 0x3f00
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PPU.vram.address = 0x3f;
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PPU.vram.address = 0x00;
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for (index = 0; index < sizeof(PALETTE); index++) {
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PPU.vram.data = PALETTE[index];
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}
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// load the text into VRAM
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// set PPU address to 0x21c9
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PPU.vram.address = 0x21;
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PPU.vram.address = 0xc9;
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for (index = 0; index < sizeof(TEXT); index++) {
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PPU.vram.data = TEXT[index];
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}
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// reset the scroll position to 0
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PPU.scroll = 0;
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PPU.scroll = 0;
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// reset the PPU address to 0x2000 (frame start)
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PPU.vram.address = 0x20;
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PPU.vram.address = 0x00;
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// turn on the screen
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PPU.mask = 0x1e;
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// infinite loop
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while (1);
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}
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