398b37124e
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@24862 a1c6a512-1295-4272-9138-f99709370657
1306 lines
38 KiB
C
1306 lines
38 KiB
C
/*
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* acpu.c - another 6502 CPU emulator
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*
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* Copyright (C) 2007-2009 Piotr Fusik
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*
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* This file is part of ASAP (Another Slight Atari Player),
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* see http://asap.sourceforge.net
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*
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* ASAP is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License as published
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* by the Free Software Foundation; either version 2 of the License,
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* or (at your option) any later version.
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*
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* ASAP is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty
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* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
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* See the GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with ASAP; if not, write to the Free Software Foundation, Inc.,
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* 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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/* How 6502 registers are stored in this emulator:
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All variables are int, because modern processors (and Java bytecode)
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tend to operate more effectively on these type than narrower ones.
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pc is really an unsigned 16-bit integer.
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a, x, y and s are unsigned 8-bit integers.
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Flags are decomposed into three variables for improved performance.
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c is either 0 or 1.
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nz contains 6502 flags N and Z.
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N is set if (nz >= 0x80). Z is set if ((nz & 0xff) == 0).
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Usually nz is simply assigned the unsigned 8-bit operation result.
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There are just a few operations (ADC in decimal mode, BIT, PLP and RTI)
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where both N and Z may be set. In these cases, N is reflected by the 8th
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(not 7th) bit of nz.
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vdi contains rarely used flags V, D and I, as a combination
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of V_FLAG, D_FLAG and I_FLAG. Other vdi bits are clear.
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"Unofficial" opcodes are not documented as "legal" 6502 opcodes.
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Their operation has been reverse-engineered on Atari 800XL and Atari 65XE.
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Unofficial opcodes are identical to C64's 6510, except for 0x8b and 0xab.
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The operation of "unstable" opcodes is partially uncertain.
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Explanation is welcome.
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Emulation of POKEY timer interrupts is included.
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Two preprocessor symbols may be used to strip the size of this emulator.
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Define ACPU_NO_DECIMAL to disable emulation of the BCD mode.
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Define ACPU_NO_UNOFFICIAL to disable emulation of unofficial opcodes. */
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#include "asap_internal.h"
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CONST_ARRAY(int, opcode_cycles)
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/* 0 1 2 3 4 5 6 7 8 9 A B C D E F */
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7, 6, 2, 8, 3, 3, 5, 5, 3, 2, 2, 2, 4, 4, 6, 6, /* 0x */
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2, 5, 2, 8, 4, 4, 6, 6, 2, 4, 2, 7, 4, 4, 7, 7, /* 1x */
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6, 6, 2, 8, 3, 3, 5, 5, 4, 2, 2, 2, 4, 4, 6, 6, /* 2x */
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2, 5, 2, 8, 4, 4, 6, 6, 2, 4, 2, 7, 4, 4, 7, 7, /* 3x */
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6, 6, 2, 8, 3, 3, 5, 5, 3, 2, 2, 2, 3, 4, 6, 6, /* 4x */
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2, 5, 2, 8, 4, 4, 6, 6, 2, 4, 2, 7, 4, 4, 7, 7, /* 5x */
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6, 6, 2, 8, 3, 3, 5, 5, 4, 2, 2, 2, 5, 4, 6, 6, /* 6x */
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2, 5, 2, 8, 4, 4, 6, 6, 2, 4, 2, 7, 4, 4, 7, 7, /* 7x */
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2, 6, 2, 6, 3, 3, 3, 3, 2, 2, 2, 2, 4, 4, 4, 4, /* 8x */
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2, 6, 2, 6, 4, 4, 4, 4, 2, 5, 2, 5, 5, 5, 5, 5, /* 9x */
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2, 6, 2, 6, 3, 3, 3, 3, 2, 2, 2, 2, 4, 4, 4, 4, /* Ax */
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2, 5, 2, 5, 4, 4, 4, 4, 2, 4, 2, 4, 4, 4, 4, 4, /* Bx */
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2, 6, 2, 8, 3, 3, 5, 5, 2, 2, 2, 2, 4, 4, 6, 6, /* Cx */
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2, 5, 2, 8, 4, 4, 6, 6, 2, 4, 2, 7, 4, 4, 7, 7, /* Dx */
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2, 6, 2, 8, 3, 3, 5, 5, 2, 2, 2, 2, 4, 4, 6, 6, /* Ex */
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2, 5, 2, 8, 4, 4, 6, 6, 2, 4, 2, 7, 4, 4, 7, 7 /* Fx */
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END_CONST_ARRAY;
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#ifdef ACPU_NO_DECIMAL
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#define DO_ADC \
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{ \
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/* binary mode */ \
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V(int, tmp) = a + data + c; \
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c = tmp >> 8; \
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vdi &= D_FLAG | I_FLAG; \
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if (((a ^ data) & 0x80) == 0 && ((data ^ tmp) & 0x80) != 0) \
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vdi += V_FLAG; \
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nz = a = tmp & 0xff; \
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}
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#define DO_SBC \
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{ \
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/* binary mode */ \
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V(int, tmp) = a - data - 1 + c; \
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c = (tmp >= 0) ? 1 : 0; \
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vdi &= D_FLAG | I_FLAG; \
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if (((a ^ tmp) & 0x80) != 0 && ((a ^ data) & 0x80) != 0) \
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vdi += V_FLAG; \
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nz = a = tmp & 0xff; \
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}
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#else /* ACPU_NO_DECIMAL */
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#define DO_ADC \
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if ((vdi & D_FLAG) == 0) { \
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/* binary mode */ \
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V(int, tmp) = a + data + c; \
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c = tmp >> 8; \
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vdi &= D_FLAG | I_FLAG; \
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if (((a ^ data) & 0x80) == 0 && ((data ^ tmp) & 0x80) != 0) \
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vdi += V_FLAG; \
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nz = a = tmp & 0xff; \
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} \
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else { \
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/* decimal mode */ \
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V(int, tmp) = (a & 0x0f) + (data & 0x0f) + c; \
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if (tmp >= 10) \
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tmp = (tmp - 10) | 0x10; \
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tmp += (a & 0xf0) + (data & 0xf0); \
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nz = ((tmp & 0x80) << 1) + ((a + data + c) & 0xff); \
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vdi &= D_FLAG | I_FLAG; \
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if (((a ^ data) & 0x80) == 0 && ((data ^ tmp) & 0x80) != 0) \
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vdi += V_FLAG; \
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if (tmp > 0x9f) \
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tmp += 0x60; \
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c = (tmp > 0xff) ? 1 : 0; \
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a = tmp & 0xff; \
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}
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#define DO_SBC \
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if ((vdi & D_FLAG) == 0) { \
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/* binary mode */ \
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V(int, tmp) = a - data - 1 + c; \
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c = (tmp >= 0) ? 1 : 0; \
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vdi &= D_FLAG | I_FLAG; \
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if (((a ^ tmp) & 0x80) != 0 && ((a ^ data) & 0x80) != 0) \
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vdi += V_FLAG; \
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nz = a = tmp & 0xff; \
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} \
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else { \
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/* decimal mode */ \
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V(int, tmp) = a - data - 1 + c; \
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V(int, al) = (a & 0x0f) - (data & 0x0f) - 1 + c; \
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V(int, ah) = (a >> 4) - (data >> 4); \
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if ((al & 0x10) != 0) { \
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al -= 6; \
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ah--; \
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} \
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if ((ah & 0x10) != 0) \
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ah -= 6; \
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c = tmp >= 0 ? 1 : 0; \
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vdi &= D_FLAG | I_FLAG; \
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if (((a ^ tmp) & 0x80) != 0 && ((a ^ data) & 0x80) != 0) \
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vdi += V_FLAG; \
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nz = tmp & 0xff; \
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a = ((ah & 0xf) << 4) + (al & 0x0f); \
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}
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#endif /* ACPU_NO_DECIMAL */
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#define zGetByte(addr) dGetByte((addr) & 0xff)
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#define PEEK dGetByte(pc)
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#define FETCH dGetByte(pc++)
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#define ABSOLUTE addr = FETCH; addr += FETCH << 8
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#define ABSOLUTE_X addr = FETCH; addr = (addr + (FETCH << 8) + x) & 0xffff
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#define ABSOLUTE_Y addr = FETCH; addr = (addr + (FETCH << 8) + y) & 0xffff
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#define ZPAGE addr = FETCH
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#define ZPAGE_X addr = (FETCH + x) & 0xff
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#define ZPAGE_Y addr = (FETCH + y) & 0xff
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#define INDIRECT_X addr = (FETCH + x) & 0xff; addr = dGetByte(addr) + (zGetByte(addr + 1) << 8)
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#define INDIRECT_Y addr = FETCH; addr = (dGetByte(addr) + (zGetByte(addr + 1) << 8) + y) & 0xffff
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#define NCYCLES_X if ((addr & 0xff) < x) ast _ cycle++
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#define NCYCLES_Y if ((addr & 0xff) < y) ast _ cycle++
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#define PL(dest) s = (s + 1) & 0xff; dest = dGetByte(0x0100 + s)
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#define PLP PL(vdi); nz = ((vdi & 0x80) << 1) + (~vdi & Z_FLAG); c = vdi & 1; vdi &= V_FLAG | D_FLAG | I_FLAG
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#define PH(data) dPutByte(0x0100 + s, data); s = (s - 1) & 0xff
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#define PHW(data) PH((data) >> 8); PH(TO_BYTE(data))
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#define PHP(bflag) PH(((nz | (nz >> 1)) & 0x80) + vdi + ((nz & 0xff) == 0 ? Z_FLAG : 0) + c + bflag)
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#define PHPB0 PHP(0x20) /* push flags with B flag clear (NMI, IRQ) */
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#define PHPB1 PHP(0x30) /* push flags with B flag set (PHP, BRK) */
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#define PHPC PHW(pc)
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#define LDA nz = a = GetByte(addr)
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#define LDA_ZP nz = a = dGetByte(addr)
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#define LDX nz = x = GetByte(addr)
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#define LDX_ZP nz = x = dGetByte(addr)
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#define LDY nz = y = GetByte(addr)
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#define LDY_ZP nz = y = dGetByte(addr)
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#define LAX nz = x = a = GetByte(addr)
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#define LAX_ZP nz = x = a = dGetByte(addr)
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#define STA PutByte(addr, a)
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#define STA_ZP dPutByte(addr, a)
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#define STX PutByte(addr, x)
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#define STX_ZP dPutByte(addr, x)
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#define STY PutByte(addr, y)
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#define STY_ZP dPutByte(addr, y)
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#define SAX data = a & x; PutByte(addr, data)
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#define SAX_ZP data = a & x; dPutByte(addr, data)
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#define CMP nz = GetByte(addr); c = (a >= nz) ? 1 : 0; nz = (a - nz) & 0xff
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#define CMP_ZP nz = dGetByte(addr); c = (a >= nz) ? 1 : 0; nz = (a - nz) & 0xff
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#define CPX nz = GetByte(addr); c = (x >= nz) ? 1 : 0; nz = (x - nz) & 0xff
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#define CPX_ZP nz = dGetByte(addr); c = (x >= nz) ? 1 : 0; nz = (x - nz) & 0xff
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#define CPY nz = GetByte(addr); c = (y >= nz) ? 1 : 0; nz = (y - nz) & 0xff
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#define CPY_ZP nz = dGetByte(addr); c = (y >= nz) ? 1 : 0; nz = (y - nz) & 0xff
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#define AND nz = a &= GetByte(addr)
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#define AND_ZP nz = a &= dGetByte(addr)
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#define ORA nz = a |= GetByte(addr)
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#define ORA_ZP nz = a |= dGetByte(addr)
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#define EOR nz = a ^= GetByte(addr)
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#define EOR_ZP nz = a ^= dGetByte(addr)
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#define ADC data = GetByte(addr); DO_ADC
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#define ADC_ZP data = dGetByte(addr); DO_ADC
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#define SBC data = GetByte(addr); DO_SBC
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#define SBC_ZP data = dGetByte(addr); DO_SBC
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#define ASL RMW_GetByte(nz, addr); c = nz >> 7; nz = (nz << 1) & 0xff; PutByte(addr, nz)
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#define ASL_ZP nz = dGetByte(addr); c = nz >> 7; nz = (nz << 1) & 0xff; dPutByte(addr, nz)
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#define ROL RMW_GetByte(nz, addr); nz = (nz << 1) + c; c = nz >> 8; nz &= 0xff; PutByte(addr, nz)
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#define ROL_ZP nz = dGetByte(addr); nz = (nz << 1) + c; c = nz >> 8; nz &= 0xff; dPutByte(addr, nz)
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#define LSR RMW_GetByte(nz, addr); c = nz & 1; nz >>= 1; PutByte(addr, nz)
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#define LSR_ZP nz = dGetByte(addr); c = nz & 1; nz >>= 1; dPutByte(addr, nz)
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#define ROR RMW_GetByte(nz, addr); nz += c << 8; c = nz & 1; nz >>= 1; PutByte(addr, nz)
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#define ROR_ZP nz = dGetByte(addr) + (c << 8); c = nz & 1; nz >>= 1; dPutByte(addr, nz)
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#define DEC RMW_GetByte(nz, addr); nz = (nz - 1) & 0xff; PutByte(addr, nz)
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#define DEC_ZP nz = dGetByte(addr); nz = (nz - 1) & 0xff; dPutByte(addr, nz)
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#define INC RMW_GetByte(nz, addr); nz = (nz + 1) & 0xff; PutByte(addr, nz)
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#define INC_ZP nz = dGetByte(addr); nz = (nz + 1) & 0xff; dPutByte(addr, nz)
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#define ASO ASL; nz = a |= nz
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#define ASO_ZP ASL_ZP; nz = a |= nz
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#define RLA ROL; nz = a &= nz
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#define RLA_ZP ROL_ZP; nz = a &= nz
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#define LSE LSR; nz = a ^= nz
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#define LSE_ZP LSR_ZP; nz = a ^= nz
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#define RRA ROR; data = nz; DO_ADC
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#define RRA_ZP ROR_ZP; data = nz; DO_ADC
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#define DCM DEC; c = (a >= nz) ? 1 : 0; nz = (a - nz) & 0xff
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#define DCM_ZP DEC_ZP; c = (a >= nz) ? 1 : 0; nz = (a - nz) & 0xff
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#define INS INC; data = nz; DO_SBC
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#define INS_ZP INC_ZP; data = nz; DO_SBC
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#define BRANCH(cond) \
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if (cond) { \
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addr = SBYTE(PEEK); \
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pc++; \
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addr += pc; \
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if ((addr ^ pc) >> 8 != 0) \
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ast _ cycle++; \
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ast _ cycle++; \
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pc = addr; \
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break; \
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} \
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pc++; \
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break
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#define CHECK_IRQ \
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if ((vdi & I_FLAG) == 0 && ast _ irqst != 0xff) { \
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PHPC; \
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PHPB0; \
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vdi |= I_FLAG; \
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pc = dGetWord(0xfffe); \
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ast _ cycle += 7; \
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}
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/* Runs 6502 emulation for the specified number of Atari scanlines.
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Each scanline is 114 cycles of which 9 is taken by ANTIC for memory refresh. */
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FUNC(void, Cpu_RunScanlines, (P(ASAP_State PTR, ast), P(int, scanlines)))
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{
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/* copy registers from ASAP_State to local variables for improved performance */
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V(int, pc);
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V(int, nz);
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V(int, a);
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V(int, x);
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V(int, y);
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V(int, c);
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V(int, s);
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V(int, vdi);
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V(int, next_event_cycle);
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V(int, cycle_limit);
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pc = ast _ cpu_pc;
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nz = ast _ cpu_nz;
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a = ast _ cpu_a;
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x = ast _ cpu_x;
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y = ast _ cpu_y;
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c = ast _ cpu_c;
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s = ast _ cpu_s;
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vdi = ast _ cpu_vdi;
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ast _ next_scanline_cycle = 114;
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next_event_cycle = 114;
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cycle_limit = 114 * scanlines;
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if (next_event_cycle > ast _ timer1_cycle)
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next_event_cycle = ast _ timer1_cycle;
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if (next_event_cycle > ast _ timer2_cycle)
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next_event_cycle = ast _ timer2_cycle;
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if (next_event_cycle > ast _ timer4_cycle)
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next_event_cycle = ast _ timer4_cycle;
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ast _ nearest_event_cycle = next_event_cycle;
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for (;;) {
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V(int, cycle);
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V(int, addr);
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V(int, data);
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cycle = ast _ cycle;
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if (cycle >= ast _ nearest_event_cycle) {
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if (cycle >= ast _ next_scanline_cycle) {
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if (++ast _ scanline_number == 312)
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ast _ scanline_number = 0;
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ast _ cycle = cycle += 9;
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ast _ next_scanline_cycle += 114;
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if (--scanlines <= 0)
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break;
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}
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next_event_cycle = ast _ next_scanline_cycle;
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#define CHECK_TIMER_IRQ(ch) \
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if (cycle >= ast _ timer##ch##_cycle) { \
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ast _ irqst &= ~ch; \
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ast _ timer##ch##_cycle = NEVER; \
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} \
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else if (next_event_cycle > ast _ timer##ch##_cycle) \
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next_event_cycle = ast _ timer##ch##_cycle;
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CHECK_TIMER_IRQ(1);
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CHECK_TIMER_IRQ(2);
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CHECK_TIMER_IRQ(4);
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ast _ nearest_event_cycle = next_event_cycle;
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CHECK_IRQ;
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}
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#ifdef ASAPSCAN
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if (cpu_trace != 0)
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trace_cpu(ast, pc, a, x, y, s, nz, vdi, c);
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#endif
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data = FETCH;
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ast _ cycle += opcode_cycles[data];
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switch (data) {
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case 0x00: /* BRK */
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pc++;
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PHPC;
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PHPB1;
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vdi |= I_FLAG;
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pc = dGetWord(0xfffe);
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break;
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case 0x01: /* ORA (ab,x) */
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INDIRECT_X;
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ORA;
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break;
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case 0x02: /* CIM [unofficial] */
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case 0x12:
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case 0x22:
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case 0x32:
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case 0x42:
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case 0x52:
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case 0x62:
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case 0x72:
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case 0x92:
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case 0xb2:
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case 0xd2:
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case 0xf2:
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ast _ scanline_number = (ast _ scanline_number + scanlines - 1) % 312;
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scanlines = 1;
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ast _ cycle = cycle_limit;
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break;
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#ifndef ACPU_NO_UNOFFICIAL
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case 0x03: /* ASO (ab,x) [unofficial] */
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INDIRECT_X;
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ASO;
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break;
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case 0x04: /* NOP ab [unofficial] */
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case 0x44:
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case 0x64:
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case 0x14: /* NOP ab,x [unofficial] */
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case 0x34:
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case 0x54:
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case 0x74:
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case 0xd4:
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case 0xf4:
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case 0x80: /* NOP #ab [unofficial] */
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case 0x82:
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case 0x89:
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case 0xc2:
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case 0xe2:
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pc++;
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break;
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case 0x07: /* ASO ab [unofficial] */
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ZPAGE;
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ASO_ZP;
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break;
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case 0x0b: /* ANC #ab [unofficial] */
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case 0x2b:
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nz = a &= FETCH;
|
|
c = nz >> 7;
|
|
break;
|
|
case 0x0c: /* NOP abcd [unofficial] */
|
|
pc += 2;
|
|
break;
|
|
case 0x0f: /* ASO abcd [unofficial] */
|
|
ABSOLUTE;
|
|
ASO;
|
|
break;
|
|
case 0x13: /* ASO (ab),y [unofficial] */
|
|
INDIRECT_Y;
|
|
ASO;
|
|
break;
|
|
case 0x17: /* ASO ab,x [unofficial] */
|
|
ZPAGE_X;
|
|
ASO_ZP;
|
|
break;
|
|
case 0x1b: /* ASO abcd,y [unofficial] */
|
|
ABSOLUTE_Y;
|
|
ASO;
|
|
break;
|
|
case 0x1c: /* NOP abcd,x [unofficial] */
|
|
case 0x3c:
|
|
case 0x5c:
|
|
case 0x7c:
|
|
case 0xdc:
|
|
case 0xfc:
|
|
if (FETCH + x >= 0x100)
|
|
ast _ cycle++;
|
|
pc++;
|
|
break;
|
|
case 0x1f: /* ASO abcd,x [unofficial] */
|
|
ABSOLUTE_X;
|
|
ASO;
|
|
break;
|
|
case 0x23: /* RLA (ab,x) [unofficial] */
|
|
INDIRECT_X;
|
|
RLA;
|
|
break;
|
|
case 0x27: /* RLA ab [unofficial] */
|
|
ZPAGE;
|
|
RLA_ZP;
|
|
break;
|
|
case 0x2f: /* RLA abcd [unofficial] */
|
|
ABSOLUTE;
|
|
RLA;
|
|
break;
|
|
case 0x33: /* RLA (ab),y [unofficial] */
|
|
INDIRECT_Y;
|
|
RLA;
|
|
break;
|
|
case 0x37: /* RLA ab,x [unofficial] */
|
|
ZPAGE_X;
|
|
RLA_ZP;
|
|
break;
|
|
case 0x3b: /* RLA abcd,y [unofficial] */
|
|
ABSOLUTE_Y;
|
|
RLA;
|
|
break;
|
|
case 0x3f: /* RLA abcd,x [unofficial] */
|
|
ABSOLUTE_X;
|
|
RLA;
|
|
break;
|
|
case 0x43: /* LSE (ab,x) [unofficial] */
|
|
INDIRECT_X;
|
|
LSE;
|
|
break;
|
|
case 0x47: /* LSE ab [unofficial] */
|
|
ZPAGE;
|
|
LSE_ZP;
|
|
break;
|
|
case 0x4b: /* ALR #ab [unofficial] */
|
|
a &= FETCH;
|
|
c = a & 1;
|
|
nz = a >>= 1;
|
|
break;
|
|
case 0x4f: /* LSE abcd [unofficial] */
|
|
ABSOLUTE;
|
|
LSE;
|
|
break;
|
|
case 0x53: /* LSE (ab),y [unofficial] */
|
|
INDIRECT_Y;
|
|
LSE;
|
|
break;
|
|
case 0x57: /* LSE ab,x [unofficial] */
|
|
ZPAGE_X;
|
|
LSE_ZP;
|
|
break;
|
|
case 0x5b: /* LSE abcd,y [unofficial] */
|
|
ABSOLUTE_Y;
|
|
LSE;
|
|
break;
|
|
case 0x5f: /* LSE abcd,x [unofficial] */
|
|
ABSOLUTE_X;
|
|
LSE;
|
|
break;
|
|
case 0x63: /* RRA (ab,x) [unofficial] */
|
|
INDIRECT_X;
|
|
RRA;
|
|
break;
|
|
case 0x67: /* RRA ab [unofficial] */
|
|
ZPAGE;
|
|
RRA_ZP;
|
|
break;
|
|
case 0x6b: /* ARR #ab [unofficial] */
|
|
data = a & FETCH;
|
|
nz = a = (data >> 1) + (c << 7);
|
|
vdi = (vdi & (D_FLAG | I_FLAG)) + ((a ^ data) & V_FLAG);
|
|
#ifdef ACPU_NO_DECIMAL
|
|
c = data >> 7;
|
|
#else
|
|
if ((vdi & D_FLAG) == 0)
|
|
c = data >> 7;
|
|
else {
|
|
if ((data & 0xf) >= 5)
|
|
a = (a & 0xf0) + ((a + 6) & 0xf);
|
|
if (data >= 0x50) {
|
|
a = (a + 0x60) & 0xff;
|
|
c = 1;
|
|
}
|
|
else
|
|
c = 0;
|
|
}
|
|
#endif
|
|
break;
|
|
case 0x6f: /* RRA abcd [unofficial] */
|
|
ABSOLUTE;
|
|
RRA;
|
|
break;
|
|
case 0x73: /* RRA (ab),y [unofficial] */
|
|
INDIRECT_Y;
|
|
RRA;
|
|
break;
|
|
case 0x77: /* RRA ab,x [unofficial] */
|
|
ZPAGE_X;
|
|
RRA_ZP;
|
|
break;
|
|
case 0x7b: /* RRA abcd,y [unofficial] */
|
|
ABSOLUTE_Y;
|
|
RRA;
|
|
break;
|
|
case 0x7f: /* RRA abcd,x [unofficial] */
|
|
ABSOLUTE_X;
|
|
RRA;
|
|
break;
|
|
case 0x83: /* SAX (ab,x) [unofficial] */
|
|
INDIRECT_X;
|
|
SAX;
|
|
break;
|
|
case 0x87: /* SAX ab [unofficial] */
|
|
ZPAGE;
|
|
SAX_ZP;
|
|
break;
|
|
case 0x8b: /* ANE #ab [unofficial] */
|
|
data = FETCH;
|
|
a &= x;
|
|
nz = a & data;
|
|
a &= data | 0xef;
|
|
break;
|
|
case 0x8f: /* SAX abcd [unofficial] */
|
|
ABSOLUTE;
|
|
SAX;
|
|
break;
|
|
case 0x93: /* SHA (ab),y [unofficial, unstable] */
|
|
ZPAGE;
|
|
data = zGetByte(addr + 1);
|
|
addr = (dGetByte(addr) + (data << 8) + y) & 0xffff;
|
|
data = a & x & (data + 1);
|
|
PutByte(addr, data);
|
|
break;
|
|
case 0x97: /* SAX ab,y [unofficial] */
|
|
ZPAGE_Y;
|
|
SAX_ZP;
|
|
break;
|
|
case 0x9b: /* SHS abcd,y [unofficial, unstable] */
|
|
/* S seems to be stable, only memory values vary */
|
|
addr = FETCH;
|
|
data = FETCH;
|
|
addr = (addr + (data << 8) + y) & 0xffff;
|
|
s = a & x;
|
|
data = s & (data + 1);
|
|
PutByte(addr, data);
|
|
break;
|
|
case 0x9c: /* SHY abcd,x [unofficial] */
|
|
addr = FETCH;
|
|
data = FETCH;
|
|
addr = (addr + (data << 8) + x) & 0xffff;
|
|
data = y & (data + 1);
|
|
PutByte(addr, data);
|
|
break;
|
|
case 0x9e: /* SHX abcd,y [unofficial] */
|
|
addr = FETCH;
|
|
data = FETCH;
|
|
addr = (addr + (data << 8) + y) & 0xffff;
|
|
data = x & (data + 1);
|
|
PutByte(addr, data);
|
|
break;
|
|
case 0x9f: /* SHA abcd,y [unofficial, unstable] */
|
|
addr = FETCH;
|
|
data = FETCH;
|
|
addr = (addr + (data << 8) + y) & 0xffff;
|
|
data = a & x & (data + 1);
|
|
PutByte(addr, data);
|
|
break;
|
|
case 0xa3: /* LAX (ab,x) [unofficial] */
|
|
INDIRECT_X;
|
|
LAX;
|
|
break;
|
|
case 0xa7: /* LAX ab [unofficial] */
|
|
ZPAGE;
|
|
LAX_ZP;
|
|
break;
|
|
case 0xab: /* ANX #ab [unofficial] */
|
|
nz = x = a &= FETCH;
|
|
break;
|
|
case 0xaf: /* LAX abcd [unofficial] */
|
|
ABSOLUTE;
|
|
LAX;
|
|
break;
|
|
case 0xb3: /* LAX (ab),y [unofficial] */
|
|
INDIRECT_Y;
|
|
NCYCLES_Y;
|
|
LAX;
|
|
break;
|
|
case 0xb7: /* LAX ab,y [unofficial] */
|
|
ZPAGE_Y;
|
|
LAX_ZP;
|
|
break;
|
|
case 0xbb: /* LAS abcd,y [unofficial] */
|
|
ABSOLUTE_Y;
|
|
NCYCLES_Y;
|
|
nz = x = a = s &= GetByte(addr);
|
|
break;
|
|
case 0xbf: /* LAX abcd,y [unofficial] */
|
|
ABSOLUTE_Y;
|
|
NCYCLES_Y;
|
|
LAX;
|
|
break;
|
|
case 0xc3: /* DCM (ab,x) [unofficial] */
|
|
INDIRECT_X;
|
|
DCM;
|
|
break;
|
|
case 0xc7: /* DCM ab [unofficial] */
|
|
ZPAGE;
|
|
DCM_ZP;
|
|
break;
|
|
case 0xcb: /* SBX #ab [unofficial] */
|
|
nz = FETCH;
|
|
x &= a;
|
|
c = (x >= nz) ? 1 : 0;
|
|
nz = x = (x - nz) & 0xff;
|
|
break;
|
|
case 0xcf: /* DCM abcd [unofficial] */
|
|
ABSOLUTE;
|
|
DCM;
|
|
break;
|
|
case 0xd3: /* DCM (ab),y [unofficial] */
|
|
INDIRECT_Y;
|
|
DCM;
|
|
break;
|
|
case 0xd7: /* DCM ab,x [unofficial] */
|
|
ZPAGE_X;
|
|
DCM_ZP;
|
|
break;
|
|
case 0xdb: /* DCM abcd,y [unofficial] */
|
|
ABSOLUTE_Y;
|
|
DCM;
|
|
break;
|
|
case 0xdf: /* DCM abcd,x [unofficial] */
|
|
ABSOLUTE_X;
|
|
DCM;
|
|
break;
|
|
case 0xe3: /* INS (ab,x) [unofficial] */
|
|
INDIRECT_X;
|
|
INS;
|
|
break;
|
|
case 0xe7: /* INS ab [unofficial] */
|
|
ZPAGE;
|
|
INS_ZP;
|
|
break;
|
|
case 0xef: /* INS abcd [unofficial] */
|
|
ABSOLUTE;
|
|
INS;
|
|
break;
|
|
case 0xf3: /* INS (ab),y [unofficial] */
|
|
INDIRECT_Y;
|
|
INS;
|
|
break;
|
|
case 0xf7: /* INS ab,x [unofficial] */
|
|
ZPAGE_X;
|
|
INS_ZP;
|
|
break;
|
|
case 0xfb: /* INS abcd,y [unofficial] */
|
|
ABSOLUTE_Y;
|
|
INS;
|
|
break;
|
|
case 0xff: /* INS abcd,x [unofficial] */
|
|
ABSOLUTE_X;
|
|
INS;
|
|
break;
|
|
#endif /* ACPU_NO_UNOFFICIAL */
|
|
case 0x05: /* ORA ab */
|
|
ZPAGE;
|
|
ORA_ZP;
|
|
break;
|
|
case 0x06: /* ASL ab */
|
|
ZPAGE;
|
|
ASL_ZP;
|
|
break;
|
|
case 0x08: /* PHP */
|
|
PHPB1;
|
|
break;
|
|
case 0x09: /* ORA #ab */
|
|
nz = a |= FETCH;
|
|
break;
|
|
case 0x0a: /* ASL */
|
|
c = a >> 7;
|
|
nz = a = (a << 1) & 0xff;
|
|
break;
|
|
case 0x0d: /* ORA abcd */
|
|
ABSOLUTE;
|
|
ORA;
|
|
break;
|
|
case 0x0e: /* ASL abcd */
|
|
ABSOLUTE;
|
|
ASL;
|
|
break;
|
|
case 0x10: /* BPL */
|
|
BRANCH(nz < 0x80);
|
|
case 0x11: /* ORA (ab),y */
|
|
INDIRECT_Y;
|
|
NCYCLES_Y;
|
|
ORA;
|
|
break;
|
|
case 0x15: /* ORA ab,x */
|
|
ZPAGE_X;
|
|
ORA_ZP;
|
|
break;
|
|
case 0x16: /* ASL ab,x */
|
|
ZPAGE_X;
|
|
ASL_ZP;
|
|
break;
|
|
case 0x18: /* CLC */
|
|
c = 0;
|
|
break;
|
|
case 0x19: /* ORA abcd,y */
|
|
ABSOLUTE_Y;
|
|
NCYCLES_Y;
|
|
ORA;
|
|
break;
|
|
case 0x1d: /* ORA abcd,x */
|
|
ABSOLUTE_X;
|
|
NCYCLES_X;
|
|
ORA;
|
|
break;
|
|
case 0x1e: /* ASL abcd,x */
|
|
ABSOLUTE_X;
|
|
ASL;
|
|
break;
|
|
case 0x20: /* JSR abcd */
|
|
addr = FETCH;
|
|
PHPC;
|
|
pc = addr + (PEEK << 8);
|
|
break;
|
|
case 0x21: /* AND (ab,x) */
|
|
INDIRECT_X;
|
|
AND;
|
|
break;
|
|
case 0x24: /* BIT ab */
|
|
ZPAGE;
|
|
nz = dGetByte(addr);
|
|
vdi = (vdi & (D_FLAG | I_FLAG)) + (nz & V_FLAG);
|
|
nz = ((nz & 0x80) << 1) + (nz & a);
|
|
break;
|
|
case 0x25: /* AND ab */
|
|
ZPAGE;
|
|
AND_ZP;
|
|
break;
|
|
case 0x26: /* ROL ab */
|
|
ZPAGE;
|
|
ROL_ZP;
|
|
break;
|
|
case 0x28: /* PLP */
|
|
PLP;
|
|
CHECK_IRQ;
|
|
break;
|
|
case 0x29: /* AND #ab */
|
|
nz = a &= FETCH;
|
|
break;
|
|
case 0x2a: /* ROL */
|
|
a = (a << 1) + c;
|
|
c = a >> 8;
|
|
nz = a &= 0xff;
|
|
break;
|
|
case 0x2c: /* BIT abcd */
|
|
ABSOLUTE;
|
|
nz = GetByte(addr);
|
|
vdi = (vdi & (D_FLAG | I_FLAG)) + (nz & V_FLAG);
|
|
nz = ((nz & 0x80) << 1) + (nz & a);
|
|
break;
|
|
case 0x2d: /* AND abcd */
|
|
ABSOLUTE;
|
|
AND;
|
|
break;
|
|
case 0x2e: /* ROL abcd */
|
|
ABSOLUTE;
|
|
ROL;
|
|
break;
|
|
case 0x30: /* BMI */
|
|
BRANCH(nz >= 0x80);
|
|
case 0x31: /* AND (ab),y */
|
|
INDIRECT_Y;
|
|
NCYCLES_Y;
|
|
AND;
|
|
break;
|
|
case 0x35: /* AND ab,x */
|
|
ZPAGE_X;
|
|
AND_ZP;
|
|
break;
|
|
case 0x36: /* ROL ab,x */
|
|
ZPAGE_X;
|
|
ROL_ZP;
|
|
break;
|
|
case 0x38: /* SEC */
|
|
c = 1;
|
|
break;
|
|
case 0x39: /* AND abcd,y */
|
|
ABSOLUTE_Y;
|
|
NCYCLES_Y;
|
|
AND;
|
|
break;
|
|
case 0x3d: /* AND abcd,x */
|
|
ABSOLUTE_X;
|
|
NCYCLES_X;
|
|
AND;
|
|
break;
|
|
case 0x3e: /* ROL abcd,x */
|
|
ABSOLUTE_X;
|
|
ROL;
|
|
break;
|
|
case 0x40: /* RTI */
|
|
PLP;
|
|
PL(pc);
|
|
PL(addr);
|
|
pc += addr << 8;
|
|
CHECK_IRQ;
|
|
break;
|
|
case 0x41: /* EOR (ab,x) */
|
|
INDIRECT_X;
|
|
EOR;
|
|
break;
|
|
case 0x45: /* EOR ab */
|
|
ZPAGE;
|
|
EOR_ZP;
|
|
break;
|
|
case 0x46: /* LSR ab */
|
|
ZPAGE;
|
|
LSR_ZP;
|
|
break;
|
|
case 0x48: /* PHA */
|
|
PH(a);
|
|
break;
|
|
case 0x49: /* EOR #ab */
|
|
nz = a ^= FETCH;
|
|
break;
|
|
case 0x4a: /* LSR */
|
|
c = a & 1;
|
|
nz = a >>= 1;
|
|
break;
|
|
case 0x4c: /* JMP abcd */
|
|
addr = FETCH;
|
|
pc = addr + (PEEK << 8);
|
|
break;
|
|
case 0x4d: /* EOR abcd */
|
|
ABSOLUTE;
|
|
EOR;
|
|
break;
|
|
case 0x4e: /* LSR abcd */
|
|
ABSOLUTE;
|
|
LSR;
|
|
break;
|
|
case 0x50: /* BVC */
|
|
BRANCH((vdi & V_FLAG) == 0);
|
|
case 0x51: /* EOR (ab),y */
|
|
INDIRECT_Y;
|
|
NCYCLES_Y;
|
|
EOR;
|
|
break;
|
|
case 0x55: /* EOR ab,x */
|
|
ZPAGE_X;
|
|
EOR_ZP;
|
|
break;
|
|
case 0x56: /* LSR ab,x */
|
|
ZPAGE_X;
|
|
LSR_ZP;
|
|
break;
|
|
case 0x58: /* CLI */
|
|
vdi &= V_FLAG | D_FLAG;
|
|
CHECK_IRQ;
|
|
break;
|
|
case 0x59: /* EOR abcd,y */
|
|
ABSOLUTE_Y;
|
|
NCYCLES_Y;
|
|
EOR;
|
|
break;
|
|
case 0x5d: /* EOR abcd,x */
|
|
ABSOLUTE_X;
|
|
NCYCLES_X;
|
|
EOR;
|
|
break;
|
|
case 0x5e: /* LSR abcd,x */
|
|
ABSOLUTE_X;
|
|
LSR;
|
|
break;
|
|
case 0x60: /* RTS */
|
|
PL(pc);
|
|
PL(addr);
|
|
pc += (addr << 8) + 1;
|
|
break;
|
|
case 0x61: /* ADC (ab,x) */
|
|
INDIRECT_X;
|
|
ADC;
|
|
break;
|
|
case 0x65: /* ADC ab */
|
|
ZPAGE;
|
|
ADC_ZP;
|
|
break;
|
|
case 0x66: /* ROR ab */
|
|
ZPAGE;
|
|
ROR_ZP;
|
|
break;
|
|
case 0x68: /* PLA */
|
|
PL(a);
|
|
nz = a;
|
|
break;
|
|
case 0x69: /* ADC #ab */
|
|
data = FETCH;
|
|
DO_ADC;
|
|
break;
|
|
case 0x6a: /* ROR */
|
|
nz = (c << 7) + (a >> 1);
|
|
c = a & 1;
|
|
a = nz;
|
|
break;
|
|
case 0x6c: /* JMP (abcd) */
|
|
ABSOLUTE;
|
|
if ((addr & 0xff) == 0xff)
|
|
pc = (dGetByte(addr - 0xff) << 8) + dGetByte(addr);
|
|
else
|
|
pc = dGetWord(addr);
|
|
break;
|
|
case 0x6d: /* ADC abcd */
|
|
ABSOLUTE;
|
|
ADC;
|
|
break;
|
|
case 0x6e: /* ROR abcd */
|
|
ABSOLUTE;
|
|
ROR;
|
|
break;
|
|
case 0x70: /* BVS */
|
|
BRANCH((vdi & V_FLAG) != 0);
|
|
case 0x71: /* ADC (ab),y */
|
|
INDIRECT_Y;
|
|
NCYCLES_Y;
|
|
ADC;
|
|
break;
|
|
case 0x75: /* ADC ab,x */
|
|
ZPAGE_X;
|
|
ADC_ZP;
|
|
break;
|
|
case 0x76: /* ROR ab,x */
|
|
ZPAGE_X;
|
|
ROR_ZP;
|
|
break;
|
|
case 0x78: /* SEI */
|
|
vdi |= I_FLAG;
|
|
break;
|
|
case 0x79: /* ADC abcd,y */
|
|
ABSOLUTE_Y;
|
|
NCYCLES_Y;
|
|
ADC;
|
|
break;
|
|
case 0x7d: /* ADC abcd,x */
|
|
ABSOLUTE_X;
|
|
NCYCLES_X;
|
|
ADC;
|
|
break;
|
|
case 0x7e: /* ROR abcd,x */
|
|
ABSOLUTE_X;
|
|
ROR;
|
|
break;
|
|
case 0x81: /* STA (ab,x) */
|
|
INDIRECT_X;
|
|
STA;
|
|
break;
|
|
case 0x84: /* STY ab */
|
|
ZPAGE;
|
|
STY_ZP;
|
|
break;
|
|
case 0x85: /* STA ab */
|
|
ZPAGE;
|
|
STA_ZP;
|
|
break;
|
|
case 0x86: /* STX ab */
|
|
ZPAGE;
|
|
STX_ZP;
|
|
break;
|
|
case 0x88: /* DEY */
|
|
nz = y = (y - 1) & 0xff;
|
|
break;
|
|
case 0x8a: /* TXA */
|
|
nz = a = x;
|
|
break;
|
|
case 0x8c: /* STY abcd */
|
|
ABSOLUTE;
|
|
STY;
|
|
break;
|
|
case 0x8d: /* STA abcd */
|
|
ABSOLUTE;
|
|
STA;
|
|
break;
|
|
case 0x8e: /* STX abcd */
|
|
ABSOLUTE;
|
|
STX;
|
|
break;
|
|
case 0x90: /* BCC */
|
|
BRANCH(c == 0);
|
|
case 0x91: /* STA (ab),y */
|
|
INDIRECT_Y;
|
|
STA;
|
|
break;
|
|
case 0x94: /* STY ab,x */
|
|
ZPAGE_X;
|
|
STY_ZP;
|
|
break;
|
|
case 0x95: /* STA ab,x */
|
|
ZPAGE_X;
|
|
STA_ZP;
|
|
break;
|
|
case 0x96: /* STX ab,y */
|
|
ZPAGE_Y;
|
|
STX_ZP;
|
|
break;
|
|
case 0x98: /* TYA */
|
|
nz = a = y;
|
|
break;
|
|
case 0x99: /* STA abcd,y */
|
|
ABSOLUTE_Y;
|
|
STA;
|
|
break;
|
|
case 0x9a: /* TXS */
|
|
s = x;
|
|
break;
|
|
case 0x9d: /* STA abcd,x */
|
|
ABSOLUTE_X;
|
|
STA;
|
|
break;
|
|
case 0xa0: /* LDY #ab */
|
|
nz = y = FETCH;
|
|
break;
|
|
case 0xa1: /* LDA (ab,x) */
|
|
INDIRECT_X;
|
|
LDA;
|
|
break;
|
|
case 0xa2: /* LDX #ab */
|
|
nz = x = FETCH;
|
|
break;
|
|
case 0xa4: /* LDY ab */
|
|
ZPAGE;
|
|
LDY_ZP;
|
|
break;
|
|
case 0xa5: /* LDA ab */
|
|
ZPAGE;
|
|
LDA_ZP;
|
|
break;
|
|
case 0xa6: /* LDX ab */
|
|
ZPAGE;
|
|
LDX_ZP;
|
|
break;
|
|
case 0xa8: /* TAY */
|
|
nz = y = a;
|
|
break;
|
|
case 0xa9: /* LDA #ab */
|
|
nz = a = FETCH;
|
|
break;
|
|
case 0xaa: /* TAX */
|
|
nz = x = a;
|
|
break;
|
|
case 0xac: /* LDY abcd */
|
|
ABSOLUTE;
|
|
LDY;
|
|
break;
|
|
case 0xad: /* LDA abcd */
|
|
ABSOLUTE;
|
|
LDA;
|
|
break;
|
|
case 0xae: /* LDX abcd */
|
|
ABSOLUTE;
|
|
LDX;
|
|
break;
|
|
case 0xb0: /* BCS */
|
|
BRANCH(c != 0);
|
|
case 0xb1: /* LDA (ab),y */
|
|
INDIRECT_Y;
|
|
NCYCLES_Y;
|
|
LDA;
|
|
break;
|
|
case 0xb4: /* LDY ab,x */
|
|
ZPAGE_X;
|
|
LDY_ZP;
|
|
break;
|
|
case 0xb5: /* LDA ab,x */
|
|
ZPAGE_X;
|
|
LDA_ZP;
|
|
break;
|
|
case 0xb6: /* LDX ab,y */
|
|
ZPAGE_Y;
|
|
LDX_ZP;
|
|
break;
|
|
case 0xb8: /* CLV */
|
|
vdi &= D_FLAG | I_FLAG;
|
|
break;
|
|
case 0xb9: /* LDA abcd,y */
|
|
ABSOLUTE_Y;
|
|
NCYCLES_Y;
|
|
LDA;
|
|
break;
|
|
case 0xba: /* TSX */
|
|
nz = x = s;
|
|
break;
|
|
case 0xbc: /* LDY abcd,x */
|
|
ABSOLUTE_X;
|
|
NCYCLES_X;
|
|
LDY;
|
|
break;
|
|
case 0xbd: /* LDA abcd,x */
|
|
ABSOLUTE_X;
|
|
NCYCLES_X;
|
|
LDA;
|
|
break;
|
|
case 0xbe: /* LDX abcd,y */
|
|
ABSOLUTE_Y;
|
|
NCYCLES_Y;
|
|
LDX;
|
|
break;
|
|
case 0xc0: /* CPY #ab */
|
|
nz = FETCH;
|
|
c = (y >= nz) ? 1 : 0;
|
|
nz = (y - nz) & 0xff;
|
|
break;
|
|
case 0xc1: /* CMP (ab,x) */
|
|
INDIRECT_X;
|
|
CMP;
|
|
break;
|
|
case 0xc4: /* CPY ab */
|
|
ZPAGE;
|
|
CPY_ZP;
|
|
break;
|
|
case 0xc5: /* CMP ab */
|
|
ZPAGE;
|
|
CMP_ZP;
|
|
break;
|
|
case 0xc6: /* DEC ab */
|
|
ZPAGE;
|
|
DEC_ZP;
|
|
break;
|
|
case 0xc8: /* INY */
|
|
nz = y = (y + 1) & 0xff;
|
|
break;
|
|
case 0xc9: /* CMP #ab */
|
|
nz = FETCH;
|
|
c = (a >= nz) ? 1 : 0;
|
|
nz = (a - nz) & 0xff;
|
|
break;
|
|
case 0xca: /* DEX */
|
|
nz = x = (x - 1) & 0xff;
|
|
break;
|
|
case 0xcc: /* CPY abcd */
|
|
ABSOLUTE;
|
|
CPY;
|
|
break;
|
|
case 0xcd: /* CMP abcd */
|
|
ABSOLUTE;
|
|
CMP;
|
|
break;
|
|
case 0xce: /* DEC abcd */
|
|
ABSOLUTE;
|
|
DEC;
|
|
break;
|
|
case 0xd0: /* BNE */
|
|
BRANCH((nz & 0xff) != 0);
|
|
case 0xd1: /* CMP (ab),y */
|
|
INDIRECT_Y;
|
|
NCYCLES_Y;
|
|
CMP;
|
|
break;
|
|
case 0xd5: /* CMP ab,x */
|
|
ZPAGE_X;
|
|
CMP_ZP;
|
|
break;
|
|
case 0xd6: /* DEC ab,x */
|
|
ZPAGE_X;
|
|
DEC_ZP;
|
|
break;
|
|
case 0xd8: /* CLD */
|
|
vdi &= V_FLAG | I_FLAG;
|
|
break;
|
|
case 0xd9: /* CMP abcd,y */
|
|
ABSOLUTE_Y;
|
|
NCYCLES_Y;
|
|
CMP;
|
|
break;
|
|
case 0xdd: /* CMP abcd,x */
|
|
ABSOLUTE_X;
|
|
NCYCLES_X;
|
|
CMP;
|
|
break;
|
|
case 0xde: /* DEC abcd,x */
|
|
ABSOLUTE_X;
|
|
DEC;
|
|
break;
|
|
case 0xe0: /* CPX #ab */
|
|
nz = FETCH;
|
|
c = (x >= nz) ? 1 : 0;
|
|
nz = (x - nz) & 0xff;
|
|
break;
|
|
case 0xe1: /* SBC (ab,x) */
|
|
INDIRECT_X;
|
|
SBC;
|
|
break;
|
|
case 0xe4: /* CPX ab */
|
|
ZPAGE;
|
|
CPX_ZP;
|
|
break;
|
|
case 0xe5: /* SBC ab */
|
|
ZPAGE;
|
|
SBC_ZP;
|
|
break;
|
|
case 0xe6: /* INC ab */
|
|
ZPAGE;
|
|
INC_ZP;
|
|
break;
|
|
case 0xe8: /* INX */
|
|
nz = x = (x + 1) & 0xff;
|
|
break;
|
|
case 0xe9: /* SBC #ab */
|
|
case 0xeb: /* SBC #ab [unofficial] */
|
|
data = FETCH;
|
|
DO_SBC;
|
|
break;
|
|
case 0xea: /* NOP */
|
|
case 0x1a: /* NOP [unofficial] */
|
|
case 0x3a:
|
|
case 0x5a:
|
|
case 0x7a:
|
|
case 0xda:
|
|
case 0xfa:
|
|
break;
|
|
case 0xec: /* CPX abcd */
|
|
ABSOLUTE;
|
|
CPX;
|
|
break;
|
|
case 0xed: /* SBC abcd */
|
|
ABSOLUTE;
|
|
SBC;
|
|
break;
|
|
case 0xee: /* INC abcd */
|
|
ABSOLUTE;
|
|
INC;
|
|
break;
|
|
case 0xf0: /* BEQ */
|
|
BRANCH((nz & 0xff) == 0);
|
|
case 0xf1: /* SBC (ab),y */
|
|
INDIRECT_Y;
|
|
NCYCLES_Y;
|
|
SBC;
|
|
break;
|
|
case 0xf5: /* SBC ab,x */
|
|
ZPAGE_X;
|
|
SBC_ZP;
|
|
break;
|
|
case 0xf6: /* INC ab,x */
|
|
ZPAGE_X;
|
|
INC_ZP;
|
|
break;
|
|
case 0xf8: /* SED */
|
|
vdi |= D_FLAG;
|
|
break;
|
|
case 0xf9: /* SBC abcd,y */
|
|
ABSOLUTE_Y;
|
|
NCYCLES_Y;
|
|
SBC;
|
|
break;
|
|
case 0xfd: /* SBC abcd,x */
|
|
ABSOLUTE_X;
|
|
NCYCLES_X;
|
|
SBC;
|
|
break;
|
|
case 0xfe: /* INC abcd,x */
|
|
ABSOLUTE_X;
|
|
INC;
|
|
break;
|
|
}
|
|
}
|
|
ast _ cpu_pc = pc;
|
|
ast _ cpu_nz = nz;
|
|
ast _ cpu_a = a;
|
|
ast _ cpu_x = x;
|
|
ast _ cpu_y = y;
|
|
ast _ cpu_c = c;
|
|
ast _ cpu_s = s;
|
|
ast _ cpu_vdi = vdi;
|
|
ast _ cycle -= cycle_limit;
|
|
if (ast _ timer1_cycle != NEVER)
|
|
ast _ timer1_cycle -= cycle_limit;
|
|
if (ast _ timer2_cycle != NEVER)
|
|
ast _ timer2_cycle -= cycle_limit;
|
|
if (ast _ timer4_cycle != NEVER)
|
|
ast _ timer4_cycle -= cycle_limit;
|
|
}
|