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https://github.com/mauiaaron/apple2.git
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c39bea9580
* Fixes crashing observed when trying to use debugger
* Various refactoring whitespace fixes
137 lines
4.6 KiB
C
137 lines
4.6 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 __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 void *WMEM;
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typedef void *RMEM;
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struct memory_vector
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{
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RMEM r;
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WMEM w;
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};
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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 (order not same as in real 6502) */
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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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/* 6502 CPU models */
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#define CPU65_NMOS 0x0
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#define CPU65_C02 0x1
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#define CPU65_FAULT 0x100 /* Undoc. opcodes are BRK */
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/* Set up the processor for a new run. Sets up opcode table. */
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extern void cpu65_set(int flags);
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/* Interrupt the processor */
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extern void cpu65_interrupt(int reason);
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extern void cpu65_run(void);
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extern void cpu65_set_stepping(int flag);
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extern void cpu65_direct_write(int ea,int data);
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extern struct memory_vector 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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extern uint8_t cpu65_do_reboot;
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#endif /* !__ASSEMBLER__ */
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#define RebootSig 0x01
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#define ResetSig 0x02
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#define DebugStepSig 0x04
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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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#define X_Reg %bl /* 6502 X register in %bl */
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#define Y_Reg %bh /* 6502 Y register in %bh */
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#define A_Reg %cl /* 6502 A register in %cl */
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#define F_Reg %ch /* 6502 flags in %ch */
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#define FF_Reg %ecx /* 6502 flags for bt */
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#define SP_Reg %edx /* 6502 Stack pointer */
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#define SP_Reg_L %dl /* 6502 Stack pointer low */
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#define SP_Reg_H %dh /* 6502 Stack pointer high */
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#define PC_Reg %si /* 6502 Program Counter */
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#define PC_Reg_E %esi /* 6502 Program Counter */
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#define EffectiveAddr %di /* Effective address */
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#define EffectiveAddr_E %edi /* Effective address */
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#ifndef __ASSEMBLER__
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/* Private data. */
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extern void *cpu65__opcodes[256];
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extern void *const cpu65__nmos[256];
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extern void *const cpu65__nmosbrk[256];
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extern void *const cpu65__cmos[256];
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extern char cpu65__opcycles[256];// cycle counter
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extern unsigned char cpu65__signal;
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#endif /* !__ASSEMBLER__ */
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