63 lines
905 B
C
63 lines
905 B
C
#include "cpu.h"
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#include <stdlib.h>
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#include <stdio.h>
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#include "bus.h"
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struct CPU* createCPU(struct Bus* parent)
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{
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struct CPU* cpu = (struct CPU*)malloc(sizeof(struct CPU));
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if (cpu == NULL)
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{
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fprintf(stderr, "Failed to create CPU, aborting.\n");
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exit(1);
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}
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// TODO: THIS IS JUST FOR THE TEST ROM
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cpu->pc = 0xC000;
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cpu->bus = parent;
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return cpu;
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}
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void destroyCPU(struct CPU* cpu)
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{
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free(cpu);
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}
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void tickCPU(struct CPU* cpu)
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{
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if (cpu->fetchedVal != 0)
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{
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cpu->fetchedVal--;
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return;
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}
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fetch(cpu);
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execute(cpu);
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}
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void tickInstr(struct CPU* cpu)
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{
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while (cpu->remainingCycles > 1)
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tickCPU(cpu);
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}
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void fetch(struct CPU* cpu)
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{
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Byte opcodeVal = readBus(cpu->bus, cpu->pc);
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cpu->currentOpcode = OPCODE_TABLE + opcodeVal;
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if (cpu->currentOpcode->op == Unknown)
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{
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fprintf(stderr, "Unknown opcode: %x", opcodeVal);
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exit(1);
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}
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}
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void execute(struct CPU* cpu)
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{
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}
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