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886 lines
17 KiB
C
886 lines
17 KiB
C
// This unit has been copied from libz80 into Collapse OS and was slighly changed
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/* =========================================================
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* libz80 - Z80 emulation library
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* =========================================================
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*
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* (C) Gabriel Gambetta (gabriel.gambetta@gmail.com) 2000 - 2012
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*
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* Version 2.1.0
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*
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* ---------------------------------------------------------
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* 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 this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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*/
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#include "z80.h"
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#include "string.h"
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#define BR (ctx->R1.br)
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#define WR (ctx->R1.wr)
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#define SETFLAG(F) setFlag(ctx, F)
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#define RESFLAG(F) resFlag(ctx, F)
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#define GETFLAG(F) getFlag(ctx, F)
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#define VALFLAG(F,V) valFlag(ctx, F, V)
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/* ---------------------------------------------------------
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* Flag tricks
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* ---------------------------------------------------------
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*
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* To avoid repeating entries in the spec files, many operations that look similar are treated as special cases
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* of a more general operation.
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*
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* For example, ADD and ADC are similar in syntax and operation - the difference is that ADC takes the carry flag
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* into account.
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*
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* So we define a general operation doArithmetic(...) which accepts a boolean parameter specifying whether to do
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* a Carry-operation or not. Then, when we parse, we can say
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*
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* (ADD|ADC) ....
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* doArithmetic(FLAG_FOR_%1)
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*
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* and everything works fine.
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*
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*/
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/* Flags for doIncDec() */
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static const int ID_INC = 0;
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static const int ID_DEC = 1;
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/* Flags for enable / disable interrupts */
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static const int IE_DI = 0;
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static const int IE_EI = 1;
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/* Flags for doSetRes() */
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static const int SR_RES = 0;
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static const int SR_SET = 1;
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/* Flags for logical / arithmetic operations */
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static const int IA_L = 0;
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static const int IA_A = 1;
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/* Flags for doArithmetic() - F1 = withCarry, F2 = isSub */
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static const int F1_ADC = 1;
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static const int F1_SBC = 1;
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static const int F1_ADD = 0;
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static const int F1_SUB = 0;
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static const int F2_ADC = 0;
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static const int F2_SBC = 1;
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static const int F2_ADD = 0;
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static const int F2_SUB = 1;
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/* Increment or decrement R, preserving bit 7 */
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#define INCR (ctx->R = (ctx->R & 0x80) | ((ctx->R + 1) & 0x7f))
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#define DECR (ctx->R = (ctx->R & 0x80) | ((ctx->R - 1) & 0x7f))
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/* ---------------------------------------------------------
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* The opcode implementations
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* ---------------------------------------------------------
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*/
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#include "opcodes_decl.h"
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typedef enum
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{
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OP_NONE,
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OP_BYTE,
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OP_OFFSET,
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OP_WORD
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} Z80OperandType;
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typedef void (*Z80OpcodeFunc) (Z80Context* ctx);
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struct Z80OpcodeEntry
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{
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Z80OpcodeFunc func;
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int operand_type;
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char* format;
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struct Z80OpcodeTable* table;
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};
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struct Z80OpcodeTable
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{
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int opcode_offset;
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struct Z80OpcodeEntry entries[256];
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};
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#include "opcodes_table.h"
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/* ---------------------------------------------------------
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* Data operations
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* ---------------------------------------------------------
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*/
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static void write8 (Z80Context* ctx, ushort addr, byte val)
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{
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ctx->tstates += 3;
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ctx->memWrite(ctx->memParam, addr, val);
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}
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static void write16 (Z80Context* ctx, ushort addr, ushort val)
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{
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write8(ctx, addr, val);
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write8(ctx, addr + 1, val >> 8);
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}
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static byte read8 (Z80Context* ctx, ushort addr)
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{
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ctx->tstates += 3;
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return ctx->memRead(ctx->memParam, addr);
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}
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static ushort read16 (Z80Context* ctx, ushort addr)
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{
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byte lsb = read8(ctx, addr);
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byte msb = read8(ctx, addr + 1);
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return msb << 8 | lsb;
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}
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static byte ioRead (Z80Context* ctx, ushort addr)
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{
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ctx->tstates += 4;
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return ctx->ioRead(ctx->ioParam, addr);
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}
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static void ioWrite (Z80Context* ctx, ushort addr, byte val)
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{
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ctx->tstates += 4;
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ctx->ioWrite(ctx->ioParam, addr, val);
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}
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/* ---------------------------------------------------------
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* Flag operations
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* ---------------------------------------------------------
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*/
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/** Sets a flag */
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static void setFlag(Z80Context* ctx, Z80Flags flag)
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{
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BR.F |= flag;
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}
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/** Resets a flag */
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static void resFlag(Z80Context* ctx, Z80Flags flag)
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{
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BR.F &= ~flag;
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}
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/** Puts a value in a flag */
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static void valFlag(Z80Context* ctx, Z80Flags flag, int val)
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{
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if (val)
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SETFLAG(flag);
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else
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RESFLAG(flag);
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}
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/** Returns a flag */
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static int getFlag(Z80Context* ctx, Z80Flags flag)
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{
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return (BR.F & flag) != 0;
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}
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/* ---------------------------------------------------------
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* Flag adjustments
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* ---------------------------------------------------------
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*/
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static int parityBit[256] = {
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1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
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0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
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0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
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1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
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0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
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1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
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1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
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0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
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0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
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1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
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1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
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0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
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1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
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0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
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0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
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1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1 };
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static void adjustFlags (Z80Context* ctx, byte val)
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{
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VALFLAG(F_5, (val & F_5) != 0);
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VALFLAG(F_3, (val & F_3) != 0);
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}
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static void adjustFlagSZP (Z80Context* ctx, byte val)
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{
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VALFLAG(F_S, (val & 0x80) != 0);
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VALFLAG(F_Z, (val == 0));
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VALFLAG(F_PV, parityBit[val]);
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}
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/* Adjust flags after AND, OR, XOR */
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static void adjustLogicFlag (Z80Context* ctx, int flagH)
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{
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VALFLAG(F_S, (BR.A & 0x80) != 0);
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VALFLAG(F_Z, (BR.A == 0));
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VALFLAG(F_H, flagH);
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VALFLAG(F_N, 0);
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VALFLAG(F_C, 0);
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VALFLAG(F_PV, parityBit[BR.A]);
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adjustFlags(ctx, BR.A);
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}
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/* ---------------------------------------------------------
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* Condition checks
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* ---------------------------------------------------------
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*/
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typedef enum
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{
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C_,
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C_Z,
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C_NZ,
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C_C,
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C_NC,
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C_M,
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C_P,
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C_PE,
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C_PO
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} Z80Condition;
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static int condition(Z80Context* ctx, Z80Condition cond)
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{
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if (cond == C_)
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return 1;
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if (cond == C_Z)
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return GETFLAG(F_Z);
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if (cond == C_NZ)
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return !GETFLAG(F_Z);
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if (cond == C_C)
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return GETFLAG(F_C);
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if (cond == C_NC)
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return !GETFLAG(F_C);
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if (cond == C_M)
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return GETFLAG(F_S);
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if (cond == C_P)
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return !GETFLAG(F_S);
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if (cond == C_PE)
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return GETFLAG(F_PV);
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/* if (cond == C_PO)*/
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return !GETFLAG(F_PV);
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}
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/* ---------------------------------------------------------
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* Generic operations
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* ---------------------------------------------------------
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*/
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static int doComplement(byte v)
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{
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if ((v & 0x80) == 0)
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return v;
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v = ~v;
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v &= 0x7F;
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v++;
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return -v;
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}
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/** Do an arithmetic operation (ADD, SUB, ADC, SBC y CP) */
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static byte doArithmetic (Z80Context* ctx, byte value, int withCarry, int isSub)
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{
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ushort res; /* To detect carry */
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if (isSub)
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{
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SETFLAG(F_N);
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VALFLAG(F_H, (((BR.A & 0x0F) - (value & 0x0F)) & 0x10) != 0);
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res = BR.A - value;
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if (withCarry && GETFLAG(F_C))
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res--;
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}
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else
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{
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RESFLAG(F_N);
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VALFLAG(F_H, (((BR.A & 0x0F) + (value & 0x0F)) & 0x10) != 0);
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res = BR.A + value;
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if (withCarry && GETFLAG(F_C))
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res++;
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}
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VALFLAG(F_S, ((res & 0x80) != 0));
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VALFLAG(F_C, ((res & 0x100) != 0));
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VALFLAG(F_Z, ((res & 0xff) == 0));
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int minuend_sign = BR.A & 0x80;
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int subtrahend_sign = value & 0x80;
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int result_sign = res & 0x80;
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int overflow;
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if(isSub)
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overflow = minuend_sign != subtrahend_sign && result_sign != minuend_sign;
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else
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overflow = minuend_sign == subtrahend_sign && result_sign != minuend_sign;
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VALFLAG(F_PV, overflow);
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adjustFlags(ctx, res);
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return (byte)(res & 0xFF);
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}
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/* Do a 16-bit addition, setting the appropriate flags. */
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static ushort doAddWord(Z80Context* ctx, ushort a1, ushort a2, int withCarry, int isSub)
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{
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if(withCarry && GETFLAG(F_C))
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a2++;
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int sum = a1;
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if(isSub)
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{
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sum -= a2;
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VALFLAG(F_H, ((a1 & 0x0fff) - (a2 & 0x0fff)) & 0x1000);
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}
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else
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{
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sum += a2;
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VALFLAG(F_H, ((a1 & 0x0fff) + (a2 & 0x0fff)) & 0x1000);
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}
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VALFLAG(F_C, sum & 0x10000);
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if(withCarry || isSub)
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{
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int minuend_sign = a1 & 0x8000;
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int subtrahend_sign = a2 & 0x8000;
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int result_sign = sum & 0x8000;
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int overflow;
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if(isSub)
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overflow = minuend_sign != subtrahend_sign && result_sign != minuend_sign;
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else
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overflow = minuend_sign == subtrahend_sign && result_sign != minuend_sign;
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VALFLAG(F_PV, overflow);
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VALFLAG(F_S, (sum & 0x8000) != 0);
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VALFLAG(F_Z, (sum & 0xFFFF) == 0);
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}
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VALFLAG(F_N, isSub);
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adjustFlags(ctx, sum >> 8);
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return sum;
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}
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static void doAND (Z80Context* ctx, byte value)
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{
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BR.A &= value;
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adjustLogicFlag(ctx, 1);
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}
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static void doOR (Z80Context* ctx, byte value)
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{
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BR.A |= value;
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adjustLogicFlag(ctx, 0);
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}
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static void doXOR (Z80Context* ctx, byte value)
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{
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BR.A ^= value;
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adjustLogicFlag(ctx, 0);
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}
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static void doBIT (Z80Context* ctx, int b, byte val)
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{
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if (val & (1 << b))
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RESFLAG(F_Z | F_PV);
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else
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SETFLAG(F_Z | F_PV);
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SETFLAG(F_H);
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RESFLAG(F_N);
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RESFLAG(F_S);
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if ((b == 7) && !GETFLAG(F_Z))
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SETFLAG(F_S);
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}
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static void doBIT_r(Z80Context* ctx, int b, byte val)
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{
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doBIT(ctx, b, val);
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VALFLAG(F_5, val & F_5);
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VALFLAG(F_3, val & F_3);
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}
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static void doBIT_indexed(Z80Context* ctx, int b, ushort address)
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{
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byte val = read8(ctx, address);
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doBIT(ctx, b, val);
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VALFLAG(F_5, (address >> 8) & F_5);
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VALFLAG(F_3, (address >> 8) & F_3);
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}
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byte doSetRes (Z80Context* ctx, int bit, int pos, byte val)
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{
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if (bit)
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val |= (1 << pos);
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else
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val &= ~(1 << pos);
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return val;
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}
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static byte doIncDec (Z80Context* ctx, byte val, int isDec)
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{
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if (isDec)
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{
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VALFLAG(F_PV, (val & 0x80) && !((val - 1) & 0x80));
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val--;
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VALFLAG(F_H, (val & 0x0F) == 0x0F);
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}
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else
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{
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VALFLAG(F_PV, !(val & 0x80) && ((val + 1) & 0x80));
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val++;
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VALFLAG(F_H, !(val & 0x0F));
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}
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VALFLAG(F_S, ((val & 0x80) != 0));
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VALFLAG(F_Z, (val == 0));
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VALFLAG(F_N, isDec);
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adjustFlags(ctx, val);
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return val;
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}
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static byte doRLC (Z80Context* ctx, int adjFlags, byte val)
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{
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VALFLAG(F_C, (val & 0x80) != 0);
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val <<= 1;
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val |= (byte)GETFLAG(F_C);
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adjustFlags(ctx, val);
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RESFLAG(F_H | F_N);
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if (adjFlags)
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adjustFlagSZP(ctx, val);
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return val;
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}
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static byte doRL (Z80Context* ctx, int adjFlags, byte val)
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{
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int CY = GETFLAG(F_C);
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VALFLAG(F_C, (val & 0x80) != 0);
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val <<= 1;
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val |= (byte)CY;
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adjustFlags(ctx, val);
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RESFLAG(F_H | F_N);
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if (adjFlags)
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adjustFlagSZP(ctx, val);
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return val;
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}
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static byte doRRC (Z80Context* ctx, int adjFlags, byte val)
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{
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VALFLAG(F_C, (val & 0x01) != 0);
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val >>= 1;
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val |= ((byte)GETFLAG(F_C) << 7);
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adjustFlags(ctx, val);
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RESFLAG(F_H | F_N);
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if (adjFlags)
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adjustFlagSZP(ctx, val);
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return val;
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}
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static byte doRR (Z80Context* ctx, int adjFlags, byte val)
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{
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int CY = GETFLAG(F_C);
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VALFLAG(F_C, (val & 0x01));
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val >>= 1;
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val |= (CY << 7);
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adjustFlags(ctx, val);
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RESFLAG(F_H | F_N);
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if (adjFlags)
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adjustFlagSZP(ctx, val);
|
|
|
|
return val;
|
|
}
|
|
|
|
|
|
static byte doSL (Z80Context* ctx, byte val, int isArith)
|
|
{
|
|
VALFLAG(F_C, (val & 0x80) != 0);
|
|
val <<= 1;
|
|
|
|
if (!isArith)
|
|
val |= 1;
|
|
|
|
adjustFlags(ctx, val);
|
|
RESFLAG(F_H | F_N);
|
|
adjustFlagSZP(ctx, val);
|
|
|
|
return val;
|
|
}
|
|
|
|
|
|
static byte doSR (Z80Context* ctx, byte val, int isArith)
|
|
{
|
|
int b = val & 0x80;
|
|
|
|
VALFLAG(F_C, (val & 0x01) != 0);
|
|
val >>= 1;
|
|
|
|
if (isArith)
|
|
val |= b;
|
|
|
|
adjustFlags(ctx, val);
|
|
RESFLAG(F_H | F_N);
|
|
adjustFlagSZP(ctx, val);
|
|
|
|
return val;
|
|
}
|
|
|
|
|
|
static void doPush (Z80Context* ctx, ushort val)
|
|
{
|
|
WR.SP--;
|
|
WR.SP--;
|
|
write16(ctx, WR.SP, val);
|
|
}
|
|
|
|
|
|
static ushort doPop (Z80Context* ctx)
|
|
{
|
|
ushort val;
|
|
val = read16(ctx, WR.SP);
|
|
WR.SP++;
|
|
WR.SP++;
|
|
return val;
|
|
}
|
|
|
|
|
|
static byte doCP_HL(Z80Context * ctx)
|
|
{
|
|
byte val = read8(ctx, WR.HL);
|
|
byte result = doArithmetic(ctx, val, 0, 1);
|
|
adjustFlags(ctx, val);
|
|
return result;
|
|
}
|
|
|
|
|
|
/* The DAA opcode
|
|
* According to the value in A and the flags set, add a value to A
|
|
* This algorithm taken from:
|
|
* http://www.worldofspectrum.org/faq/reference/z80reference.htm
|
|
* and verified against the specification in the Zilog
|
|
* Z80 Family CPU User Manual, rev. 04, Dec. 2004, pp. 166-167
|
|
*/
|
|
|
|
static void doDAA(Z80Context * ctx) {
|
|
int correction_factor = 0x00;
|
|
int carry = 0;
|
|
if(BR.A > 0x99 || GETFLAG(F_C)) {
|
|
correction_factor |= 0x60;
|
|
carry = 1;
|
|
}
|
|
if((BR.A & 0x0f) > 9 || GETFLAG(F_H))
|
|
correction_factor |= 0x06;
|
|
int a_before = BR.A;
|
|
if(GETFLAG(F_N))
|
|
BR.A -= correction_factor;
|
|
else
|
|
BR.A += correction_factor;
|
|
VALFLAG(F_H, (a_before ^ BR.A) & 0x10);
|
|
VALFLAG(F_C, carry);
|
|
VALFLAG(F_S, (BR.A & 0x80) != 0);
|
|
VALFLAG(F_Z, (BR.A == 0));
|
|
VALFLAG(F_PV, parityBit[BR.A]);
|
|
adjustFlags(ctx, BR.A);
|
|
}
|
|
|
|
#include "opcodes_impl.c"
|
|
|
|
|
|
/* ---------------------------------------------------------
|
|
* The top-level functions
|
|
* ---------------------------------------------------------
|
|
*/
|
|
|
|
|
|
static void do_execute(Z80Context* ctx)
|
|
{
|
|
struct Z80OpcodeTable* current = &opcodes_main;
|
|
struct Z80OpcodeEntry* entries = current->entries;
|
|
Z80OpcodeFunc func;
|
|
|
|
byte opcode;
|
|
int offset = 0;
|
|
do
|
|
{
|
|
if (ctx->exec_int_vector)
|
|
{
|
|
opcode = ctx->int_vector;
|
|
ctx->tstates += 6;
|
|
}
|
|
else
|
|
{
|
|
opcode = read8(ctx, ctx->PC + offset);
|
|
ctx->PC++;
|
|
ctx->tstates += 1;
|
|
}
|
|
|
|
INCR;
|
|
func = entries[opcode].func;
|
|
if (func != NULL)
|
|
{
|
|
ctx->PC -= offset;
|
|
func(ctx);
|
|
ctx->PC += offset;
|
|
break;
|
|
}
|
|
else if (entries[opcode].table != NULL)
|
|
{
|
|
current = entries[opcode].table;
|
|
entries = current->entries;
|
|
offset = current->opcode_offset;
|
|
if (offset > 0)
|
|
DECR;
|
|
}
|
|
|
|
else
|
|
{
|
|
/* NOP */
|
|
break;
|
|
}
|
|
} while(1);
|
|
}
|
|
|
|
|
|
static void unhalt(Z80Context* ctx)
|
|
{
|
|
if (ctx->halted)
|
|
{
|
|
ctx->halted = 0;
|
|
ctx->PC++;
|
|
}
|
|
}
|
|
|
|
|
|
static void do_nmi(Z80Context* ctx)
|
|
{
|
|
unhalt(ctx);
|
|
ctx->IFF2 = ctx->IFF1;
|
|
ctx->IFF1 = 0;
|
|
doPush(ctx, ctx->PC);
|
|
ctx->PC = 0x0066;
|
|
ctx->nmi_req = 0;
|
|
ctx->tstates += 5;
|
|
}
|
|
|
|
|
|
static void do_int(Z80Context* ctx)
|
|
{
|
|
unhalt(ctx);
|
|
ctx->IFF1 = 0;
|
|
ctx->IFF2 = 0;
|
|
ctx->int_req = 0;
|
|
if (ctx->IM == 0)
|
|
{
|
|
ctx->exec_int_vector = 1;
|
|
do_execute(ctx);
|
|
ctx->exec_int_vector = 0;
|
|
}
|
|
else if (ctx->IM == 1)
|
|
{
|
|
doPush(ctx, ctx->PC);
|
|
ctx->PC = 0x0038;
|
|
ctx->tstates += 7;
|
|
}
|
|
else if (ctx->IM == 2)
|
|
{
|
|
doPush(ctx, ctx->PC);
|
|
ushort vector_address = (ctx->I << 8) | ctx->int_vector;
|
|
ctx->PC = read16(ctx, vector_address);
|
|
ctx->tstates += 7;
|
|
}
|
|
}
|
|
|
|
|
|
void Z80Execute (Z80Context* ctx)
|
|
{
|
|
if (ctx->nmi_req)
|
|
do_nmi(ctx);
|
|
else if (ctx->int_req && !ctx->defer_int && ctx->IFF1)
|
|
do_int(ctx);
|
|
else
|
|
{
|
|
ctx->defer_int = 0;
|
|
do_execute(ctx);
|
|
}
|
|
}
|
|
|
|
|
|
unsigned Z80ExecuteTStates(Z80Context* ctx, unsigned tstates)
|
|
{
|
|
ctx->tstates = 0;
|
|
while (ctx->tstates < tstates)
|
|
Z80Execute(ctx);
|
|
return ctx->tstates;
|
|
}
|
|
|
|
|
|
void Z80Debug (Z80Context* ctx, char* dump, char* decode)
|
|
{
|
|
char tmp[20];
|
|
struct Z80OpcodeTable* current = &opcodes_main;
|
|
struct Z80OpcodeEntry* entries = current->entries;
|
|
char* fmt;
|
|
byte opcode;
|
|
ushort parm;
|
|
int offset = 0;
|
|
int PC = ctx->PC;
|
|
int size = 0;
|
|
|
|
if (dump)
|
|
dump[0] = 0;
|
|
|
|
if (decode)
|
|
decode[0] = 0;
|
|
|
|
do
|
|
{
|
|
opcode = read8(ctx, PC + offset);
|
|
size++;
|
|
|
|
PC++;
|
|
fmt = entries[opcode].format;
|
|
if (fmt != NULL)
|
|
{
|
|
PC -= offset;
|
|
parm = read16(ctx, PC);
|
|
|
|
if (entries[opcode].operand_type == OP_NONE)
|
|
size++;
|
|
else
|
|
size += 2;
|
|
if (entries[opcode].operand_type != OP_WORD)
|
|
{
|
|
parm &= 0xFF;
|
|
size--;
|
|
}
|
|
|
|
if (decode)
|
|
sprintf(decode, fmt, parm);
|
|
|
|
PC += offset;
|
|
break;
|
|
}
|
|
else if (entries[opcode].table != NULL)
|
|
{
|
|
current = entries[opcode].table;
|
|
entries = current->entries;
|
|
offset = current->opcode_offset;
|
|
}
|
|
|
|
else
|
|
{
|
|
if (decode != NULL)
|
|
strcpy(decode, "NOP (ignored)");
|
|
break;
|
|
}
|
|
} while(1);
|
|
|
|
if (dump)
|
|
{
|
|
for (offset = 0; offset < size; offset++)
|
|
{
|
|
sprintf(tmp, "%02X", read8(ctx, ctx->PC + offset));
|
|
strcat(dump, tmp);
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
void Z80RESET (Z80Context* ctx)
|
|
{
|
|
ctx->PC = 0x0000;
|
|
BR.F = 0;
|
|
ctx->IM = 0;
|
|
ctx->IFF1 = ctx->IFF2 = 0;
|
|
ctx->R = 0;
|
|
ctx->I = 0;
|
|
ctx->halted = 0;
|
|
ctx->tstates = 0;
|
|
ctx->nmi_req = 0;
|
|
ctx->int_req = 0;
|
|
ctx->defer_int = 0;
|
|
ctx->exec_int_vector = 0;
|
|
}
|
|
|
|
|
|
void Z80INT (Z80Context* ctx, byte value)
|
|
{
|
|
ctx->int_req = 1;
|
|
ctx->int_vector = value;
|
|
}
|
|
|
|
|
|
void Z80NMI (Z80Context* ctx)
|
|
{
|
|
ctx->nmi_req = 1;
|
|
}
|
|
|