mirror of
https://github.com/hsoft/collapseos.git
synced 2024-11-27 14:28:06 +11:00
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>
|
|
#include <stdbool.h>
|
|
|
|
#define VDP_VRAM_SIZE 0x4020
|
|
#define VDP_SCREENW (32*8)
|
|
#define VDP_SCREENH (24*8)
|
|
// Offset of the name table
|
|
#define VDP_NTABLE_OFFSET 0x3800
|
|
|
|
|
|
typedef struct {
|
|
// the last 0x20 is palette RAM
|
|
uint8_t vram[VDP_VRAM_SIZE];
|
|
uint8_t regs[0x10];
|
|
uint8_t cmdlsb;
|
|
bool has_cmdlsb;
|
|
uint16_t curaddr;
|
|
} VDP;
|
|
|
|
void vdp_init(VDP *vdp);
|
|
uint8_t vdp_cmd_rd(VDP *vdp);
|
|
void vdp_cmd_wr(VDP *vdp, uint8_t val);
|
|
uint8_t vdp_data_rd(VDP *vdp);
|
|
void vdp_data_wr(VDP *vdp, uint8_t val);
|
|
// result is a RGB value
|
|
uint8_t vdp_pixel(VDP *vdp, uint16_t x, uint16_t y);
|