mirror of
https://github.com/cc65/cc65.git
synced 2024-11-18 00:07:21 +00:00
126 lines
4.8 KiB
C
126 lines
4.8 KiB
C
/*****************************************************************************/
|
|
/* */
|
|
/* 6502.h */
|
|
/* */
|
|
/* 6502 specific declarations */
|
|
/* */
|
|
/* */
|
|
/* */
|
|
/* (C) 1998-2001 Ullrich von Bassewitz */
|
|
/* Wacholderweg 14 */
|
|
/* D-70597 Stuttgart */
|
|
/* EMail: uz@musoftware.de */
|
|
/* */
|
|
/* */
|
|
/* 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
|
|
|
|
|
|
|
|
/* Possible returns of getcpu() */
|
|
#define CPU_6502 0
|
|
#define CPU_65C02 1
|
|
#define CPU_65816 2
|
|
|
|
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 */
|
|
#ifdef __OBSOLETE_FLAGS__
|
|
#define F_NEG 0x80 /* N flag */
|
|
#define F_OVF 0x40 /* V flag */
|
|
#define F_BRK 0x10 /* B flag */
|
|
#define F_DEC 0x08 /* D flag */
|
|
#define F_IEN 0x04 /* I flag */
|
|
#define F_ZERO 0x02 /* Z flag */
|
|
#define F_CARRY 0x01 /* C flag */
|
|
#endif
|
|
|
|
/* 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, return the old address */
|
|
|
|
void reset_brk (void);
|
|
/* Reset the break vector to the original value */
|
|
|
|
|
|
|
|
/* End of 6502.h */
|
|
#endif
|
|
|
|
|
|
|