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Diffstat (limited to 'include/z80.h')
| -rw-r--r-- | include/z80.h | 256 |
1 files changed, 256 insertions, 0 deletions
diff --git a/include/z80.h b/include/z80.h new file mode 100644 index 0000000..ef24fd0 --- /dev/null +++ b/include/z80.h @@ -0,0 +1,256 @@ +/* + + z80 - Z80 emulation + + Copyright (C) 2021 Ian Cowburn <ianc@noddybox.co.uk> + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, see <http://www.gnu.org/licenses/> + + ------------------------------------------------------------------------- + + $Id: z80.h 61 2008-11-03 17:07:32Z ianc $ + +*/ + +#ifndef Z80_H +#define Z80_H "$Id: z80.h 61 2008-11-03 17:07:32Z ianc $" + +#include <stdio.h> + +/* Configuration +*/ +#include "z80_config.h" + + +/* ---------------------------------------- TYPES +*/ + +/* Large unsigned type +*/ +typedef unsigned long Z80Val; + + +/* 8-bit type. The emulation will exit with code 2 if this isn't 8 bits. +*/ +typedef unsigned char Z80Byte; + + +/* 8-bit signed type. The emulation will exit with code 2 if this isn't 8 bits. +*/ +typedef signed char Z80Relative; + + +/* 16-bit type. The emulation will exit with code 2 if this isn't 16 bits. +*/ +typedef unsigned short Z80Word; + + +/* A Z80 16-bit register. To access the HI/LO component use the indexes + Z80_HI_WORD and Z80_LO_WORD which will be initialised once Z80Init has been + called. +*/ +typedef union +{ + Z80Word w; + Z80Byte b[2]; +} Z80Reg; + +extern int Z80_HI_WORD; +extern int Z80_LO_WORD; + + +/* The processor +*/ +struct Z80Private; + +typedef struct +{ + Z80Word PC; + + Z80Reg AF; + Z80Reg BC; + Z80Reg DE; + Z80Reg HL; + + Z80Word AF_; + Z80Word BC_; + Z80Word DE_; + Z80Word HL_; + + Z80Reg IX; + Z80Reg IY; + + Z80Word SP; + + Z80Byte IFF1; + Z80Byte IFF2; + Z80Byte IM; + Z80Byte I; + Z80Byte R; + + struct Z80Private *priv; +} Z80; + + +/* Interfaces used to handle memory +*/ +typedef Z80Byte (*Z80ReadMemory)(Z80 *cpu, Z80Word address); +typedef void (*Z80WriteMemory)(Z80 *cpu, Z80Word address, Z80Byte value); + + +/* Interfaces needed to handle ports (IN/OUT commands) +*/ +typedef Z80Byte (*Z80ReadPort)(Z80 *cpu, Z80Word address); +typedef void (*Z80WritePort)(Z80 *cpu, Z80Word address, Z80Byte value); + + +/* Callback. Callback should return TRUE for processing to continue. +*/ +typedef int (*Z80Callback)(Z80 *cpu, Z80Val data); + + +/* Callback reasons + + eZ80_Instruction Called before the initial fetch for an instruction + (called just to once no matter how many bytes the + instruction is made up of). + + eZ80_EDHook Called when an undefined ED opcode is executed. + + eZ80_Halt Called when the HALT instruction is hit and released. + + eZ80_RETI Called when the RETI instruction is executed +*/ +typedef enum +{ + eZ80_Instruction, /* data = no cycles since reset */ + eZ80_EDHook, /* data = byte after ED opcode (only for NOP opcodes) */ + eZ80_Halt, /* data = 1 halt raised, 0 halt cleared by int */ + eZ80_RETI, /* data = ignored */ + eZ80_NO_CALLBACK /* leave at end */ +} Z80CallbackReason; + + +/* Flags in the F register +*/ +typedef enum +{ + eZ80_Carry =0x01, + eZ80_Neg =0x02, + eZ80_PV =0x04, + eZ80_Hidden3 =0x08, + eZ80_HalfCarry =0x10, + eZ80_Hidden5 =0x20, + eZ80_Zero =0x40, + eZ80_Sign =0x80 +} Z80FlagRegister; + + +/* Disassembly label -- only useful if ENABLE_DISASSEMBLER is set. + Labels are stored as an array, where a NULL in the label field marks + the end of the list. +*/ +typedef struct +{ + Z80Word address; + const char *label; +} Z80Label; + + +/* ---------------------------------------- INTERFACES +*/ + + +/* Initialises the processor. +*/ +#ifdef ENABLE_ARRAY_MEMORY +Z80 *Z80Init(Z80ReadPort read_port, + Z80WritePort write_port); +#else +Z80 *Z80Init(Z80ReadMemory read_memory, + Z80WriteMemory write_memory, + Z80ReadPort read_port, + Z80WritePort write_port, + Z80ReadMemory read_for_disassem); +#endif + + +/* Resets the processor. +*/ +void Z80Reset(Z80 *cpu); + + +/* Lodge a callback to be invoked after special events. Returns FALSE + if the callback couldn't be lodged (there is a max of 10 callbacks per + reason). +*/ +int Z80LodgeCallback(Z80 *cpu, + Z80CallbackReason reason, + Z80Callback callback); + + +/* Remove a callback. Does nothing if reason was not lodged with + Z80LodgeCallback() +*/ +void Z80RemoveCallback(Z80 *cpu, + Z80CallbackReason reason, + Z80Callback callback); + + +/* Cause an interrupt before the next opcode. + devbyte is the byte generated by the device (if any). +*/ +void Z80Interrupt(Z80 *cpu, Z80Byte devbyte); + + +/* Cause an NMI +*/ +void Z80NMI(Z80 *cpu); + + +/* Execute a single instruction. Returns FALSE if any callback returned + FALSE. +*/ +int Z80SingleStep(Z80 *cpu); + + +/* Executes until a callback returns FALSE (never returns otherwise) +*/ +void Z80Exec(Z80 *cpu); + + +/* Manipulate the cylce count of the Z80 +*/ +Z80Val Z80Cycles(Z80 *cpu); +void Z80ResetCycles(Z80 *cpu, Z80Val cycles); + + +/* Set address to label mappings for the disassembler +*/ +void Z80SetLabels(Z80Label labels[]); + + +/* Simple disassembly of memory accessed through read_for_disassem, or + Z80_MEMORY as appropriate. addr is updated on exit. +*/ +const char *Z80Disassemble(Z80 *cpu, Z80Word *addr); + +/* Allows the CPU state to be saved/loaded from a stream +*/ +void Z80SaveSnapshot(Z80 *cpu, FILE *fp); +void Z80LoadSnapshot(Z80 *cpu, FILE *fp); + +#endif + +/* END OF FILE */ |