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cc65/include/6502.h
2018-12-30 03:49:26 -05:00

141 lines
5.3 KiB
C

/*****************************************************************************/
/* */
/* 6502.h */
/* */
/* 6502 specific declarations */
/* */
/* */
/* */
/* (C) 1998-2012, Ullrich von Bassewitz */
/* Roemerstrasse 52 */
/* D-70794 Filderstadt */
/* EMail: uz@cc65.org */
/* */
/* */
/* This software is provided 'as-is', without any expressed or implied */
/* warranty. In no event will the authors be held liable for any damages */
/* arising from the use of this software. */
/* */
/* Permission is granted to anyone to use this software for any purpose, */
/* including commercial applications, and to alter it and redistribute it */
/* freely, subject to the following restrictions: */
/* */
/* 1. The origin of this software must not be misrepresented; you must not */
/* claim that you wrote the original software. If you use this software */
/* in a product, an acknowledgment in the product documentation would be */
/* appreciated but is not required. */
/* 2. Altered source versions must be plainly marked as such, and must not */
/* be misrepresented as being the original software. */
/* 3. This notice may not be removed or altered from any source */
/* distribution. */
/* */
/*****************************************************************************/
#ifndef _6502_H
#define _6502_H
/* We need size_t */
#ifndef _HAVE_size_t
#define _HAVE_size_t
typedef unsigned size_t;
#endif
/* Possible returns of getcpu() */
#define CPU_6502 0
#define CPU_65C02 1
#define CPU_65816 2
#define CPU_4510 3
#define CPU_65SC02 4
#define CPU_65CE02 5
#define CPU_HUC6280 6
#define CPU_2A0x 7
#define CPU_45GS02 8
unsigned char getcpu (void);
/* Detect the CPU the program is running on */
/* Macros for CPU instructions */
#define BRK() __asm__ ("brk")
#define CLI() __asm__ ("cli")
#define SEI() __asm__ ("sei")
/* Struct that holds the registers for the sys function */
struct regs {
unsigned char a; /* A register value */
unsigned char x; /* X register value */
unsigned char y; /* Y register value */
unsigned char flags; /* Flags value */
unsigned pc; /* Program counter */
};
/* Defines for the flags in the regs structure */
#define F6502_N 0x80 /* N flag */
#define F6502_V 0x40 /* V flag */
#define F6502_B 0x10 /* B flag */
#define F6502_D 0x08 /* D flag */
#define F6502_I 0x04 /* I flag */
#define F6502_Z 0x02 /* Z flag */
#define F6502_C 0x01 /* C flag */
/* Function to call any machine language subroutine. All registers in the
** regs structure are passed into the routine and the results are passed
** out. The B flag is ignored on input. The called routine must end with
** an RTS.
*/
void __fastcall__ _sys (struct regs* r);
/* Set and reset the break vector. The given user function is called if
** a break occurs. The values of the registers may be read from the brk_...
** variables. The value in brk_pc will point to the address that contains
** the brk instruction.
** The set_brk function will install an exit handler that will reset the
** vector if the program ends.
*/
extern unsigned char brk_a; /* A register value */
extern unsigned char brk_x; /* X register value */
extern unsigned char brk_y; /* Y register value */
extern unsigned char brk_sr; /* Status register */
extern unsigned brk_pc; /* PC value */
typedef void (*brk_handler) (void);
/* Type of the break handler */
void __fastcall__ set_brk (brk_handler f);
/* Set the break vector to the given address */
void reset_brk (void);
/* Reset the break vector to the original value */
/* Possible returns for irq_handler() */
#define IRQ_NOT_HANDLED 0
#define IRQ_HANDLED 1
typedef unsigned char (*irq_handler) (void);
/* Type of the C level interrupt request handler */
void __fastcall__ set_irq (irq_handler f, void *stack_addr, size_t stack_size);
/* Set the C level interrupt request vector to the given address */
void reset_irq (void);
/* Reset the C level interrupt request vector */
/* End of 6502.h */
#endif