66 lines
1.4 KiB
C
66 lines
1.4 KiB
C
//
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// Created by william on 10/15/23.
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//
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#ifndef CPU_CPU_H
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#define CPU_CPU_H
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#include <stdbool.h>
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#include "memory.h"
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// Reference: https://www.nesdev.org/wiki/Status_flags
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#define CPU_STATUS_CARRY_MASK 0x01
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#define CPU_STATUS_ZERO_MASK 0x02
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#define CPU_STATUS_INTERRUPT_DISABLE_MASK 0x04
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#define CPU_STATUS_DECIMAL_MASK 0x08
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#define CPU_STATUS_B_MASK 0x10
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#define CPU_STATUS_I_MASK 0x20
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#define CPU_STATUS_OVERFLOW_MASK 0x40
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#define CPU_STATUS_NEGATIVE_MASK 0x80
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#define CPU_STACK_ADDR 0x0100
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// Reference: https://www.nesdev.org/obelisk-6502-guide/registers.html
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typedef struct {
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address program_counter;
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byte stack_pointer;
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byte accumulator;
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byte x;
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byte y;
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byte status;
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} CpuRegisters;
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enum OperandType {
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OPERAND_TYPE_ACCUMULATOR,
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OPERAND_TYPE_IMMEDIATE,
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OPERAND_TYPE_ADDRESS
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};
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typedef struct {
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word value;
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enum OperandType type;
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bool is_page_crossing;
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} Operand;
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char* operand_name(Operand *operand);
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CpuRegisters* cpu_get_registers();
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byte cpu_get_flag(byte mask);
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void cpu_set_flag(bool set, byte mask);
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byte cpu_get_next_byte();
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word cpu_get_next_word();
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byte cpu_peek_byte(address addr);
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word cpu_peek_word(address addr);
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void cpu_push_byte(byte value, address addr);
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void cpu_stack_push(byte value);
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void cpu_stack_push_context();
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byte cpu_stack_pop();
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void cpu_stack_pop_context();
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void cpu_add_cycles(unsigned int cycle_count);
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#endif //CPU_CPU_H
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