mirror of https://github.com/trudnai/Steve2.git
58 lines
1.3 KiB
Objective-C
58 lines
1.3 KiB
Objective-C
//
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// 6502.h
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// 6502
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//
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// Created by Tamas Rudnai on 7/22/19.
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// Copyright © 2019 GameAlloy. All rights reserved.
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//
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#ifndef __6502_H__
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#define __6502_H__
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#import "stdint.h"
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#ifdef DEBUG
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#define dbgPrintf(format, ...) printf (format, ## __VA_ARGS__)
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#else
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#define dbgPrintf(format, ...)
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#endif
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typedef struct m6502_s {
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uint8_t A; // Accumulator
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uint8_t X; // X index register
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uint8_t Y; // Y index register
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union {
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uint8_t instr; // Instruction
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struct {
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uint8_t aaa:3;
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uint8_t bbb:3;
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uint8_t cc:2;
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};
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};
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union {
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uint8_t sr; // Status Register as 1 byte
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struct {
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uint8_t N:1; // Negative Flag
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uint8_t V:1; // Overflow Flag ???
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uint8_t B:2; // B Flag
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uint8_t D:1; // Decimal Flag
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uint8_t I:1; // Interrupt Flag
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uint8_t Z:1; // Zero Flag
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uint8_t C:1; // Carry Flag
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} flags; // Status Register
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};
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uint16_t pc; // Program Counter
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uint16_t sp; // Stack Pointer
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unsigned clk; // Clock Counter
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} m6502_s;
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extern m6502_s m6502;
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extern uint8_t RAM[ 64 * 1024 ];
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extern void tst6502();
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#endif /* __6502_H__ */
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