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#pragma once
#define VCPU_FREQ 600
#define DTST_FREQ 60
#define SCREEN_FREQ 60
#define REG_FLAG 0xF
typedef struct VCPU_State {
// Program Counter (16 bits but only 12 bits used (4096 memory addresses))
unsigned short PC;
// Index register (16 bits but only 12 bits used (4096 memory addresses))
unsigned short I;
// Stack register (16 bits)
unsigned short S;
unsigned short stack[100]; // Emulated stack
// General purpose registers (8 bits each)
// Note last one often used as a flag register
unsigned char V[16];
// Delay timer (8 bits)
unsigned char DT;
// Sound timer (8 bits)
unsigned char ST;
// Intruction (opcode + decoded fields)
unsigned short opcode;
unsigned char X;
unsigned char Y;
unsigned char N;
unsigned char NN;
unsigned short NNN;
// Keypressed
int keypressed; // Not 0 if a key was pressed
unsigned char key;
// Count VCPU ticks
int dt_ticks;
int st_ticks;
int screen_ticks;
} VCPU_State;
void VCPUInit();
void VCPUFetch();
void VCPUDecode();
void VCPUExecute();
void VCPUTick();
void VCPUDoubleDabble(unsigned char x, unsigned char *u, unsigned char *t, unsigned char *h);
void VCPUDump();
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