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120 lines
3.8 KiB
C
120 lines
3.8 KiB
C
/*
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* Apple // emulator for Linux: Virtual 6502/65C02 interface
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*
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* Copyright 1994 Alexander Jean-Claude Bottema
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* Copyright 1995 Stephen Lee
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* Copyright 1997, 1998 Aaron Culliney
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* Copyright 1998, 1999, 2000 Michael Deutschmann
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*
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* This software package is subject to the GNU General Public License
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* version 2 or later (your choice) as published by the Free Software
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* Foundation.
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*
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* THERE ARE NO WARRANTIES WHATSOEVER.
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*
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*/
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#ifndef __CPU_H_
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#define __CPU_H_
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#if !defined(__ASSEMBLER__)
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#include <sys/types.h>
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#include <stdint.h>
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/* types */
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typedef struct memory_vector_t {
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void *r;
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void *w;
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} memory_vector_t;
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struct cpu65_state
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{
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uint16_t pc; /* Program counter */
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uint8_t a; /* Accumulator */
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uint8_t f; /* Flags (host-order) */
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uint8_t x; /* X Index register */
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uint8_t y; /* Y Index register */
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uint8_t sp; /* Stack Pointer */
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};
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struct cpu65_extra
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{
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uint16_t ea; /* Last effective address */
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uint8_t d; /* Last data byte written */
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uint8_t rw; /* 1 = read occured, 2 = write, 3 = both */
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uint8_t opcode; /* Last opcode */
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uint8_t opcycles; /* Last opcode extra cycles */
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};
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/* Set up the processor for a new run. Sets up opcode table. */
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extern void cpu65_init();
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/* Interrupt the processor */
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extern void cpu65_interrupt(int reason);
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extern void cpu65_uninterrupt(int reason);
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extern void cpu65_run(void);
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extern void cpu65_direct_write(int ea,int data);
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extern memory_vector_t cpu65_vmem[65536];
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extern struct cpu65_state cpu65_current;
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extern struct cpu65_extra cpu65_debug;
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extern unsigned char cpu65_flags_encode[256];
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extern unsigned char cpu65_flags_decode[256];
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extern int16_t cpu65_cycle_count;
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extern int16_t cpu65_cycles_to_execute;
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#endif /* !__ASSEMBLER__ */
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#define ResetSig 0x02
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#define IRQ6522 0x08
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#define IRQSpeech 0x10
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#define IRQSSC 0x20
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#define IRQMouse 0x40
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#define IRQGeneric 0x80
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/* Note: These are *not* the bit positions used for the flags in the P
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* register of a real 6502. Rather, they have been distorted so that C,
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* N and Z match the analogous flags in the _80386_ flags register.
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*
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* Additionally, V matches the position of the overflow flag in the high byte
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* of the 80386 register.
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*
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*/
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#define C_Flag 0x1 /* 6502 Carry */
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#define X_Flag 0x2 /* 6502 Xtra */
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#define I_Flag 0x4 /* 6502 Interrupt disable */
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#define V_Flag 0x8 /* 6502 Overflow */
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#define B_Flag 0x10 /* 6502 Break */
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#define D_Flag 0x20 /* 6502 Decimal mode */
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#define Z_Flag 0x40 /* 6502 Zero */
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#define N_Flag 0x80 /* 6502 Neg */
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#define C_Flag_Bit 8 /* 6502 Carry */
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#define X_Flag_Bit 9 /* 6502 Xtra */
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#define I_Flag_Bit 10 /* 6502 Interrupt disable */
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#define V_Flag_Bit 11 /* 6502 Overflow */
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#define B_Flag_Bit 12 /* 6502 Break */
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#define D_Flag_Bit 13 /* 6502 Decimal mode */
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#define Z_Flag_Bit 14 /* 6502 Zero */
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#define N_Flag_Bit 15 /* 6502 Neg */
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/*
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* These are the 6502 Flags bit positions
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*/
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#define C_Flag_6502 0x1 // [C]arry
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#define Z_Flag_6502 0x2 // [Z]ero
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#define I_Flag_6502 0x4 // [I]nterrupt
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#define D_Flag_6502 0x8 // [D]ecimal
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#define B_Flag_6502 0x10 // [B]reak
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#define X_Flag_6502 0x20 // [X]tra (reserved)...
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#define V_Flag_6502 0x40 // o[V]erflow
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#define N_Flag_6502 0x80 // [N]egative
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#endif // whole file
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