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6acd22492c
VDP kinda works. Can see the Collapse OS prompt with SMS base recipe if `STDIO_GETC` gets replaced with infinite loop (no input emul yet).
27 lines
614 B
C
27 lines
614 B
C
#include <stdint.h>
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#include <stdbool.h>
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#define VDP_VRAM_SIZE 0x4020
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#define VDP_SCREENW (32*8)
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#define VDP_SCREENH (24*8)
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// Offset of the name table
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#define VDP_NTABLE_OFFSET 0x3800
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typedef struct {
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// the last 0x20 is palette RAM
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uint8_t vram[VDP_VRAM_SIZE];
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uint8_t regs[0x10];
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uint8_t cmdlsb;
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bool has_cmdlsb;
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uint16_t curaddr;
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} VDP;
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void vdp_init(VDP *vdp);
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uint8_t vdp_cmd_rd(VDP *vdp);
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void vdp_cmd_wr(VDP *vdp, uint8_t val);
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uint8_t vdp_data_rd(VDP *vdp);
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void vdp_data_wr(VDP *vdp, uint8_t val);
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// result is a RGB value
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uint8_t vdp_pixel(VDP *vdp, uint16_t x, uint16_t y);
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