1 /*****************************************************************************/
5 /* 6502 specific declarations */
9 /* (C) 1998-2012, Ullrich von Bassewitz */
10 /* Roemerstrasse 52 */
11 /* D-70794 Filderstadt */
12 /* EMail: uz@cc65.org */
15 /* This software is provided 'as-is', without any expressed or implied */
16 /* warranty. In no event will the authors be held liable for any damages */
17 /* arising from the use of this software. */
19 /* Permission is granted to anyone to use this software for any purpose, */
20 /* including commercial applications, and to alter it and redistribute it */
21 /* freely, subject to the following restrictions: */
23 /* 1. The origin of this software must not be misrepresented; you must not */
24 /* claim that you wrote the original software. If you use this software */
25 /* in a product, an acknowledgment in the product documentation would be */
26 /* appreciated but is not required. */
27 /* 2. Altered source versions must be plainly marked as such, and must not */
28 /* be misrepresented as being the original software. */
29 /* 3. This notice may not be removed or altered from any source */
32 /*****************************************************************************/
44 typedef unsigned size_t;
49 /* Possible returns of getcpu() */
60 unsigned char getcpu (void);
61 /* Detect the CPU the program is running on */
65 /* Macros for CPU instructions */
66 #define BRK() __asm__ ("brk")
67 #define CLI() __asm__ ("cli")
68 #define SEI() __asm__ ("sei")
72 /* Struct that holds the registers for the sys function */
74 unsigned char a; /* A register value */
75 unsigned char x; /* X register value */
76 unsigned char y; /* Y register value */
77 unsigned char flags; /* Flags value */
78 unsigned pc; /* Program counter */
81 /* Defines for the flags in the regs structure */
82 #define F6502_N 0x80 /* N flag */
83 #define F6502_V 0x40 /* V flag */
84 #define F6502_B 0x10 /* B flag */
85 #define F6502_D 0x08 /* D flag */
86 #define F6502_I 0x04 /* I flag */
87 #define F6502_Z 0x02 /* Z flag */
88 #define F6502_C 0x01 /* C flag */
90 /* Function to call any machine language subroutine. All registers in the
91 ** regs structure are passed into the routine and the results are passed
92 ** out. The B flag is ignored on input. The called routine must end with
95 void __fastcall__ _sys (struct regs* r);
99 /* Set and reset the break vector. The given user function is called if
100 ** a break occurs. The values of the registers may be read from the brk_...
101 ** variables. The value in brk_pc will point to the address that contains
102 ** the brk instruction.
103 ** The set_brk function will install an exit handler that will reset the
104 ** vector if the program ends.
107 extern unsigned char brk_a; /* A register value */
108 extern unsigned char brk_x; /* X register value */
109 extern unsigned char brk_y; /* Y register value */
110 extern unsigned char brk_sr; /* Status register */
111 extern unsigned brk_pc; /* PC value */
113 typedef void (*brk_handler) (void);
114 /* Type of the break handler */
116 void __fastcall__ set_brk (brk_handler f);
117 /* Set the break vector to the given address */
119 void reset_brk (void);
120 /* Reset the break vector to the original value */
124 /* Possible returns for irq_handler() */
125 #define IRQ_NOT_HANDLED 0
126 #define IRQ_HANDLED 1
128 typedef unsigned char (*irq_handler) (void);
129 /* Type of the C level interrupt request handler */
131 void __fastcall__ set_irq (irq_handler f, void *stack_addr, size_t stack_size);
132 /* Set the C level interrupt request vector to the given address */
134 void reset_irq (void);
135 /* Reset the C level interrupt request vector */