905 lines
32 KiB
C
Vendored
905 lines
32 KiB
C
Vendored
/* Z80 API
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______ ______ ______
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/\___ \/\ __ \\ __ \
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____ \/__/ /\_\ __ \\ \/\ \ ________________________________________________
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| /\_____\\_____\\_____\ |
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| Zilog \/_____//_____//_____/ CPU Emulator |
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| Copyright (C) 1999-2024 Manuel Sainz de Baranda y Goñi. |
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| This emulator is free software: you can redistribute it and/or modify it |
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| under the terms of the GNU Lesser General Public License as published by |
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| the Free Software Foundation, either version 3 of the License, or (at your |
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| option) any later version. |
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| |
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| This emulator is distributed in the hope that it will be useful, but |
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| WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY |
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| or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public |
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| License for more details. |
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| |
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| You should have received a copy of the GNU Lesser General Public License |
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| along with this emulator. If not, see <http://www.gnu.org/licenses/>. |
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| |
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'=============================================================================*/
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#ifndef Z80_H
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/** @file Z80.h
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* @brief Zilog Z80 CPU emulator.
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*
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* @details The Z80 library implements a fast, small and accurate emulator
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* of the Zilog Z80 that emulates all that is known to date about this CPU,
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* including the undocumented behaviors, MEMPTR, Q and the special RESET.
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*
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* @version 0.2
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* @date 2024
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* @author Manuel Sainz de Baranda y Goñi */
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#ifdef Z80_DEPENDENCIES_HEADER
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# define Z80_H
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# include Z80_DEPENDENCIES_HEADER
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# undef Z80_H
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#else
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# include <Z/macros/language.h>
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# include <Z/types/bitwise.h>
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#endif
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#ifndef Z80_API
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# if defined(Z80_STATIC) || defined(__DOXYGEN__)
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# define Z80_API
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# else
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# define Z80_API Z_API_IMPORT
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# endif
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#endif
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/** @brief Major version number of the Z80 library. */
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#define Z80_LIBRARY_VERSION_MAJOR 0
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/** @brief Minor version number of the Z80 library. */
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#define Z80_LIBRARY_VERSION_MINOR 2
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/** @brief Micro version number of the Z80 library. */
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#define Z80_LIBRARY_VERSION_MICRO 0
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/** @brief String literal with the version number of the Z80 library. */
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#define Z80_LIBRARY_VERSION_STRING "0.2"
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/** @brief Maximum number of clock cycles that <tt>@ref z80_run</tt> and
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* <tt>@ref z80_execute</tt> can emulate. */
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#define Z80_MAXIMUM_CYCLES (Z_USIZE_MAXIMUM - Z_USIZE(30))
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/** @brief Maximum number of clock cycles that <tt>@ref z80_run</tt> will
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* emulate if instructed to execute 1 clock cycle.
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*
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* This is the number of clock cycles it takes to execute the longest
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* instruction through interrupt mode 0, not counting the M-cycle used to fetch
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* a @c 0xDD or @c 0xFD prefix. For <tt>@ref z80_execute</tt>, subtract 4 clock
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* cycles from this value. */
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#define Z80_MAXIMUM_CYCLES_PER_STEP 25
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/** @brief Minimum number of clock cycles that <tt>@ref z80_run</tt> or
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* <tt>@ref z80_execute</tt> will emulate if instructed to execute 1 clock
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* cycle. */
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#define Z80_MINIMUM_CYCLES_PER_STEP 4
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/** @brief Opcode interpreted as a trap by the Z80 library. It corresponds to
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* the <tt>ld h,h</tt> instruction in the Z80 ISA. */
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#define Z80_HOOK 0x64
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#define Z80_SF 128 /**< @brief Bitmask of the Z80 S flag. */
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#define Z80_ZF 64 /**< @brief Bitmask of the Z80 Z flag. */
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#define Z80_YF 32 /**< @brief Bitmask of the Z80 Y flag. */
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#define Z80_HF 16 /**< @brief Bitmask of the Z80 H flag. */
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#define Z80_XF 8 /**< @brief Bitmask of the Z80 X flag. */
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#define Z80_PF 4 /**< @brief Bitmask of the Z80 P/V flag. */
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#define Z80_NF 2 /**< @brief Bitmask of the Z80 N flag. */
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#define Z80_CF 1 /**< @brief Bitmask of the Z80 C flag. */
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typedef struct Z80 Z80;
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/** @brief Defines a pointer to a <tt>@ref Z80</tt> callback function invoked to
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* perform a read operation.
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*
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* @param context The <tt>@ref Z80::context</tt> of the calling object.
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* @param address The memory address or I/O port to read from.
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* @return The byte read. */
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typedef zuint8 (* Z80Read)(void *context, zuint16 address);
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/** @brief Defines a pointer to a <tt>@ref Z80</tt> callback function invoked to
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* perform a write operation.
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*
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* @param context The <tt>@ref Z80::context</tt> of the calling object.
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* @param address The memory address or I/O port to write to.
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* @param value The byte to write. */
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typedef void (* Z80Write)(void *context, zuint16 address, zuint8 value);
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/** @brief Defines a pointer to a <tt>@ref Z80</tt> callback function invoked to
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* notify a signal change on the HALT line.
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*
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* @param context The <tt>@ref Z80::context</tt> of the calling object.
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* @param signal A code specifying the type of signal change. */
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typedef void (* Z80Halt)(void *context, zuint8 signal);
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/** @brief Defines a pointer to a <tt>@ref Z80</tt> callback function invoked to
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* notify an event.
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*
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* @param context The <tt>@ref Z80::context</tt> of the calling object. */
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typedef void (* Z80Notify)(void *context);
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/** @brief Defines a pointer to a <tt>@ref Z80</tt> callback function invoked to
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* delegate the emulation of an illegal instruction.
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*
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* @param cpu The calling object.
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* @param opcode The illegal opcode.
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* @return The number of clock cycles consumed by the instruction. */
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typedef zuint8 (* Z80Illegal)(Z80 *cpu, zuint8 opcode);
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/** @struct Z80 Z80.h
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*
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* @brief A Z80 CPU emulator.
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*
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* A @c Z80 object contains the state of an emulated Z80 CPU, pointers to
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* callback functions that interconnect the emulator with the external logic
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* and a context that is passed to these functions.
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*
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* Because no constructor function is provided, it is mandatory to directly
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* initialize all callback pointers and <tt>@ref Z80::options</tt> before using
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* an object of this type. Optional callbacks must be set to @c Z_NULL when not
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* in use. */
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struct Z80 {
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/** @brief Number of clock cycles already executed. */
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zusize cycles;
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/** @brief Maximum number of clock cycles to be executed. */
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zusize cycle_limit;
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/** @brief Pointer to pass as the first argument to all callback
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* functions.
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*
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* This member is intended to hold a reference to the context to which
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* the object belongs. It is safe not to initialize it when this is not
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* necessary. */
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void *context;
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/** @brief Invoked to perform an opcode fetch.
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*
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* This callback indicates the beginning of an opcode fetch M-cycle.
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* The function must return the byte located at the memory address
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* specified by the second argument. */
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Z80Read fetch_opcode;
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/** @brief Invoked to perform a memory read on instruction data.
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*
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* This callback indicates the beginning of a memory read M-cycle
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* during which the CPU fetches one byte of instruction data (i.e., one
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* byte of the instruction that is neither a prefix nor an opcode). The
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* function must return the byte located at the memory address
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* specified by the second argument. */
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Z80Read fetch;
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/** @brief Invoked to perform a memory read.
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*
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* This callback indicates the beginning of a memory read M-cycle. The
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* function must return the byte located at the memory address
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* specified by the second argument. */
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Z80Read read;
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/** @brief Invoked to perform a memory write.
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*
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* This callback indicates the beginning of a memory write M-cycle. The
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* function must write the third argument into the memory location
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* specified by the second argument. */
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Z80Write write;
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/** @brief Invoked to perform an I/O port read.
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*
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* This callback indicates the beginning of an I/O read M-cycle. The
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* function must return the byte read from the I/O port specified by
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* the second argument. */
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Z80Read in;
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/** @brief Invoked to perform an I/O port write.
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*
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* This callback indicates the beginning of an I/O write M-cycle. The
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* function must write the third argument to the I/O port specified by
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* the second argument. */
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Z80Write out;
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/** @brief Invoked to notify a signal change on the HALT line.
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*
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* This callback is optional and must be set to @c Z_NULL when not in
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* use. Its invocation is always deferred until the next emulation step
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* so that the emulator can abort the signal change if any invalidating
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* condition occurs, such as the acceptance of an interrupt during the
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* execution of a @c halt instruction.
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*
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* The second parameter of the function specifies the type of signal
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* change and can only contain a boolean value if the Z80 library has
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* not been built with special RESET support:
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*
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* - @c 1 indicates that the HALT line is going low during the last
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* clock cycle of a @c halt instruction, which means that the CPU
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* is entering the HALT state.
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*
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* - @c 0 indicates that the HALT line is going high during the last
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* clock cycle of an internal NOP executed during the HALT state,
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* i.e., the CPU is exiting the HALT state due to an interrupt or
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* normal RESET.
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*
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* If the library has been built with special RESET support, the values
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* <tt>@ref Z80_HALT_EXIT_EARLY</tt> and <tt>@ref Z80_HALT_CANCEL</tt>
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* are also possible for the second parameter. */
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Z80Halt halt;
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/** @brief Invoked to perform an opcode fetch that corresponds to an
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* internal NOP.
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*
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* This callback indicates the beginning of an opcode fetch M-cycle of
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* 4 clock cycles that is generated in the following two cases:
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*
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* - During the HALT state, the CPU repeatedly executes an internal NOP
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* that fetches the next opcode after the @c halt instruction without
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* incrementing the PC register. This opcode is read again and again
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* until an exit condition occurs (i.e., NMI, INT or RESET).
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*
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* - After detecting a special RESET signal, the CPU completes the
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* ongoing instruction or interrupt response and then zeroes the PC
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* register during the first clock cycle of the next M1 cycle. If no
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* interrupt has been accepted at the end of the instruction or
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* interrupt response, the CPU produces an internal NOP to allow for
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* the fetch-execute overlap to take place, during which it fetches
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* the next opcode and zeroes PC.
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*
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* This callback is optional but note that setting it to @c Z_NULL is
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* equivalent to enabling <tt>@ref Z80_OPTION_HALT_SKIP</tt>. */
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Z80Read nop;
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/** @brief Invoked to perform an opcode fetch that corresponds to a
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* non-maskable interrupt acknowledge M-cycle.
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*
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* This callback is optional and must be set to @c Z_NULL when not in
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* use. It indicates the beginning of an NMI acknowledge M-cycle. The
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* value returned by the function is ignored. */
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Z80Read nmia;
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/** @brief Invoked to perform a data bus read that corresponds to a
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* maskable interrupt acknowledge M-cycle.
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*
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* This callback is optional and must be set to @c Z_NULL when not in
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* use. It indicates the beginning of an INT acknowledge M-cycle. The
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* function must return the byte that the interrupting I/O device
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* supplies to the CPU via the data bus during this M-cycle.
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*
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* When this callback is @c Z_NULL, the emulator assumes that the value
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* read from the data bus is @c 0xFF. */
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Z80Read inta;
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/** @brief Invoked to perform a memory read on instruction data during a
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* maskable interrupt response in mode 0.
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*
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* The role of this callback is analogous to that of
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* <tt>@ref Z80::fetch</tt>, but it is specific to the INT response in
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* mode 0. Ideally, the function should return a byte of instruction
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* data that the interrupting I/O device supplies to the CPU via the
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* data bus, but depending on the emulated hardware, the device may not
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* be able to do this during a memory read M-cycle because the memory
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* is addressed instead, in which case the function must return the
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* byte located at the memory address specified by the second
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* parameter.
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*
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* This callback will only be invoked if <tt>@ref Z80::inta</tt> is not
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* @c Z_NULL and returns an opcode that implies subsequent memory read
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* M-cycles to fetch the non-opcode bytes of the instruction, so it is
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* safe not to initialize it or set it to @c Z_NULL if such a scenario
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* is not possible. */
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Z80Read int_fetch;
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/** @brief Invoked to notify that an <tt>ld i,a</tt> instruction has
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* been fetched.
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*
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* This callback is optional and must be set to @c Z_NULL when not in
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* use. It is invoked before executing the instruction. */
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Z80Notify ld_i_a;
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/** @brief Invoked to notify that an <tt>ld r,a</tt> instruction has
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* been fetched.
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*
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* This callback is optional and must be set to @c Z_NULL when not in
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* use. It is invoked before executing the instruction. */
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Z80Notify ld_r_a;
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/** @brief Invoked to notify that a @c reti instruction has been
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* fetched.
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*
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* This callback is optional and must be set to @c Z_NULL when not in
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* use. It is invoked before executing the instruction. */
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Z80Notify reti;
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/** @brief Invoked to notify that a @c retn instruction has been
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* fetched.
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*
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* This callback is optional and must be set to @c Z_NULL when not in
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* use. It is invoked before executing the instruction. */
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Z80Notify retn;
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/** @brief Invoked when a trap is fetched.
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*
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* This callback is optional and must be set to @c Z_NULL when not in
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* use, in which case the opcode of the trap will be executed normally.
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* The function receives the memory address of the trap as the second
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* parameter and must return the opcode to be executed instead of the
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* trap. If the function returns a trap (i.e., <tt>@ref Z80_HOOK</tt>),
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* the emulator will do nothing, so the trap will be fetched again
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* unless the function has modified <tt>@ref Z80::pc</tt> or replaced
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* the trap in memory with another opcode. Also note that returning a
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* trap does not revert the increment of <tt>@ref Z80::r</tt> performed
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* before each opcode fetch. */
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Z80Read hook;
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/** @brief Invoked to delegate the execution of an illegal instruction.
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*
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* This callback is optional and must be set to @c Z_NULL when not in
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* use. Only those instructions with the @c 0xED prefix that behave the
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* same as two consecutive @c nop instructions are considered illegal.
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* The function receives the illegal opcode as the second parameter and
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* must return the number of clock cycles taken by the instruction.
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*
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* At the time of invoking this callback, and relative to the start of
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* the instruction, only <tt>@ref Z80::r</tt> has been incremented
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* (twice), so <tt>@ref Z80::pc</tt> still contains the memory address
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* of the @c 0xED prefix. */
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Z80Illegal illegal;
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/** @brief Temporary storage used for instruction fetch. */
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ZInt32 data;
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ZInt16 ix_iy[2]; /**< @brief Index registers, IX and IY. */
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ZInt16 pc; /**< @brief Register PC (program counter). */
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ZInt16 sp; /**< @brief Register SP (stack pointer). */
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/** @brief Temporary index register.
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*
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* All instructions with the @c 0xDD prefix behave exactly the same as
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* their counterparts with the @c 0xFD prefix, differing only in the
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* index register: the former use IX, whereas the latter use IY. When
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* one of these prefixes is fetched, the corresponding index register
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* is copied into this member; the instruction logic is then executed
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* and finally this member is copied back into the index register. */
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ZInt16 xy;
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ZInt16 memptr; /**< @brief Register MEMPTR, also known as WZ. */
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ZInt16 af; /**< @brief Register pair AF (accumulator and flags). */
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ZInt16 bc; /**< @brief Register pair BC. */
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ZInt16 de; /**< @brief Register pair DE. */
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ZInt16 hl; /**< @brief Register pair HL. */
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ZInt16 af_; /**< @brief Register pair AF'. */
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ZInt16 bc_; /**< @brief Register pair BC'. */
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ZInt16 de_; /**< @brief Register pair DE'. */
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ZInt16 hl_; /**< @brief Register pair HL'. */
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zuint8 r; /**< @brief Register R (memory refresh). */
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zuint8 i; /**< @brief Register I (interrupt vector base). */
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/** @brief Backup of bit 7 of the R register.
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*
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* The Z80 CPU increments the R register during each M1 cycle without
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* altering its most significant bit, commonly known as R7. However,
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* the emulator only performs normal full-byte increments for speed
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* reasons, which eventually corrupts R7.
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*
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* Before entering the execution loop, both <tt>@ref z80_execute</tt>
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* and <tt>@ref z80_run</tt> copy <tt>@ref Z80::r</tt> into this member
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* to preserve the value of R7, so that they can restore it before
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* returning. The emulation of the <tt>ld r, a</tt> instruction also
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* updates the value of this member. */
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zuint8 r7;
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/** @brief Maskable interrupt mode.
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*
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* Contains the number of the maskable interrupt mode in use: @c 0,
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* @c 1 or @c 2. */
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zuint8 im;
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/** @brief Requests pending to be responded. */
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zuint8 request;
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/** @brief Type of unfinished operation to be resumed. */
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zuint8 resume;
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zuint8 iff1; /**< @brief Interrupt enable flip-flop #1 (IFF1). */
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zuint8 iff2; /**< @brief Interrupt enable flip-flop #2 (IFF2). */
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zuint8 q; /**< @brief Pseudo-register Q. */
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/** @brief Emulation options.
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*
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* This member specifies the different emulation options that are
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* enabled. It is mandatory to initialize it before using the emulator.
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* Setting it to @c 0 disables all options. */
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zuint8 options;
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/** @brief State of the INT line.
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*
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* The value of this member is @c 1 if the INT line is low; otherwise,
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* @c 0. */
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zuint8 int_line;
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/** @brief State of the HALT line.
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*
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* The value of this member is @c 1 if the HALT line is low; otherwise,
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* @c 0. The emulator updates this member before invoking
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* <tt>@ref Z80::halt</tt>, not after. */
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zuint8 halt_line;
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};
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/** @brief <tt>@ref Z80::options</tt> bitmask that enables emulation of the
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* <tt>out (c),255</tt> instruction, specific to the Zilog Z80 CMOS. */
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#define Z80_OPTION_OUT_VC_255 1
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|
/** @brief <tt>@ref Z80::options</tt> bitmask that enables emulation of the bug
|
|
* affecting the Zilog Z80 NMOS, which causes the P/V flag to be reset when a
|
|
* maskable interrupt is accepted during the execution of the
|
|
* <tt>ld a,{i|r}</tt> instructions. */
|
|
|
|
#define Z80_OPTION_LD_A_IR_BUG 2
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|
|
/** @brief <tt>@ref Z80::options</tt> bitmask that enables the HALTskip
|
|
* optimization. */
|
|
|
|
#define Z80_OPTION_HALT_SKIP 4
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|
|
/** @brief <tt>@ref Z80::options</tt> bitmask that enables the XQ factor in the
|
|
* emulation of the @c ccf and @c scf instructions. */
|
|
|
|
#define Z80_OPTION_XQ 8
|
|
|
|
/** @brief <tt>@ref Z80::options</tt> bitmask that enables notifications for any
|
|
* @c reti or @c retn instruction executed during the interrupt mode 0
|
|
* response. */
|
|
|
|
#define Z80_OPTION_IM0_RETX_NOTIFICATIONS 16
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|
|
|
/** @brief <tt>@ref Z80::options</tt> bitmask that enables the YQ factor in the
|
|
* emulation of the @c ccf and @c scf instructions. */
|
|
|
|
#define Z80_OPTION_YQ 32
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|
|
|
/** @brief <tt>@ref Z80::options</tt> bitmask that enables full emulation of the
|
|
* Zilog NMOS models. */
|
|
|
|
#define Z80_MODEL_ZILOG_NMOS \
|
|
(Z80_OPTION_LD_A_IR_BUG | Z80_OPTION_XQ | Z80_OPTION_YQ)
|
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|
|
/** @brief <tt>@ref Z80::options</tt> bitmask that enables full emulation of the
|
|
* Zilog CMOS models. */
|
|
|
|
#define Z80_MODEL_ZILOG_CMOS \
|
|
(Z80_OPTION_OUT_VC_255 | Z80_OPTION_XQ | Z80_OPTION_YQ)
|
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|
|
/** @brief <tt>@ref Z80::options</tt> bitmask that enables full emulation of the
|
|
* NEC NMOS models. */
|
|
|
|
#define Z80_MODEL_NEC_NMOS \
|
|
Z80_OPTION_LD_A_IR_BUG
|
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|
|
/** @brief <tt>@ref Z80::options</tt> bitmask that enables full emulation of the
|
|
* ST CMOS models. */
|
|
|
|
#define Z80_MODEL_ST_CMOS \
|
|
(Z80_OPTION_OUT_VC_255 | Z80_OPTION_LD_A_IR_BUG | Z80_OPTION_YQ)
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/** @brief <tt>@ref Z80::request</tt> bitmask that prevents the NMI signal from
|
|
* being accepted. */
|
|
|
|
#define Z80_REQUEST_REJECT_NMI 2
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|
|
/** @brief <tt>@ref Z80::request</tt> bitmask indicating that an NMI signal has
|
|
* been received. */
|
|
|
|
#define Z80_REQUEST_NMI 4
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|
|
/** @brief <tt>@ref Z80::request</tt> bitmask indicating that the INT line is
|
|
* low and interrupts are enabled. */
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|
|
#define Z80_REQUEST_INT 8
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/** @brief <tt>@ref Z80::request</tt> bitmask indicating that a special RESET
|
|
* signal has been received. */
|
|
|
|
#define Z80_REQUEST_SPECIAL_RESET 16
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|
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/** @brief <tt>@ref Z80::resume</tt> value indicating that the emulator ran out
|
|
* of clock cycles during the HALT state. */
|
|
|
|
#define Z80_RESUME_HALT 1
|
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|
|
/** @brief <tt>@ref Z80::resume</tt> value indicating that the emulator ran out
|
|
* of clock cycles by fetching a prefix @c 0xDD or @c 0xFD. */
|
|
|
|
#define Z80_RESUME_XY 2
|
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|
|
/** @brief <tt>@ref Z80::resume</tt> value indicating that the emulator ran out
|
|
* of clock cycles by fetching a prefix @c 0xDD or @c 0xFD, during a maskable
|
|
* interrupt response in mode 0. */
|
|
|
|
#define Z80_RESUME_IM0_XY 3
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|
|
|
/** @brief Value of the second parameter of <tt>@ref Z80::halt</tt> when the
|
|
* HALT line goes high due to a special RESET signal. */
|
|
|
|
#define Z80_HALT_EXIT_EARLY 2
|
|
|
|
/** @brief Value of the second paratemer of <tt>@ref Z80::halt</tt> when the
|
|
* HALT line goes low and then high due to a special RESET signal during the
|
|
* execution of a @c halt instruction. */
|
|
|
|
#define Z80_HALT_CANCEL 3
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|
|
/** @brief Accesses the MEMPTR register of a <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_MEMPTR(object) (object).memptr.uint16_value
|
|
|
|
/** @brief Accesses the PC register of a <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_PC(object) (object).pc.uint16_value
|
|
|
|
/** @brief Accesses the SP register of a <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_SP(object) (object).sp.uint16_value
|
|
|
|
/** @brief Accesses the temporary index register of a <tt>@ref Z80</tt> @p
|
|
* object */
|
|
|
|
#define Z80_XY(object) (object).xy.uint16_value
|
|
|
|
/** @brief Accesses the IX register of a <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_IX(object) (object).ix_iy[0].uint16_value
|
|
|
|
/** @brief Accesses the IY register of a <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_IY(object) (object).ix_iy[1].uint16_value
|
|
|
|
/** @brief Accesses the AF register of a <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_AF(object) (object).af.uint16_value
|
|
|
|
/** @brief Accesses the BC register of a <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_BC(object) (object).bc.uint16_value
|
|
|
|
/** @brief Accesses the DE register of a <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_DE(object) (object).de.uint16_value
|
|
|
|
/** @brief Accesses the HL register of a <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_HL(object) (object).hl.uint16_value
|
|
|
|
/** @brief Accesses the AF' register of a <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_AF_(object) (object).af_.uint16_value
|
|
|
|
/** @brief Accesses the BC' register of a <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_BC_(object) (object).bc_.uint16_value
|
|
|
|
/** @brief Accesses the DE' register of a <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_DE_(object) (object).de_.uint16_value
|
|
|
|
/** @brief Accesses the HL' register of a <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_HL_(object) (object).hl_.uint16_value
|
|
|
|
/** @brief Accesses the most significant byte of the MEMPTR register of a
|
|
* <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_MEMPTRH(object) (object).memptr.uint8_values.at_1
|
|
|
|
/** @brief Accesses the least significant byte of the MEMPTR register of a
|
|
* <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_MEMPTRL(object) (object).memptr.uint8_values.at_0
|
|
|
|
/** @brief Accesses the most significant byte of the PC register of a
|
|
* <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_PCH(object) (object).pc.uint8_values.at_1
|
|
|
|
/** @brief Accesses the least significant byte of the PC register of a
|
|
* <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_PCL(object) (object).pc.uint8_values.at_0
|
|
|
|
/** @brief Accesses the most significant byte of the SP register of a
|
|
* <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_SPH(object) (object).sp.uint8_values.at_1
|
|
|
|
/** @brief Accesses the least significant byte of the SP register of a
|
|
* <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_SPL(object) (object).sp.uint8_values.at_0
|
|
|
|
/** @brief Accesses the most significant byte of the temporary index register
|
|
* of a <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_XYH(object) (object).xy.uint8_values.at_1
|
|
|
|
/** @brief Accesses the least significant byte of the temporary index register
|
|
* of a <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_XYL(object) (object).xy.uint8_values.at_0
|
|
|
|
/** @brief Accesses the IXH register of a <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_IXH(object) (object).ix_iy[0].uint8_values.at_1
|
|
|
|
/** @brief Accesses the IXL register of a <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_IXL(object) (object).ix_iy[0].uint8_values.at_0
|
|
|
|
/** @brief Accesses the IYH register of a <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_IYH(object) (object).ix_iy[1].uint8_values.at_1
|
|
|
|
/** @brief Accesses the IYL register of a <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_IYL(object) (object).ix_iy[1].uint8_values.at_0
|
|
|
|
/** @brief Accesses the A register of a <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_A(object) (object).af.uint8_values.at_1
|
|
|
|
/** @brief Accesses the F register of a <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_F(object) (object).af.uint8_values.at_0
|
|
|
|
/** @brief Accesses the B register of a <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_B(object) (object).bc.uint8_values.at_1
|
|
|
|
/** @brief Accesses the C register of a <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_C(object) (object).bc.uint8_values.at_0
|
|
|
|
/** @brief Accesses the D register of a <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_D(object) (object).de.uint8_values.at_1
|
|
|
|
/** @brief Accesses the E register of a <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_E(object) (object).de.uint8_values.at_0
|
|
|
|
/** @brief Accesses the H register of a <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_H(object) (object).hl.uint8_values.at_1
|
|
|
|
/** @brief Accesses the L register of a <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_L(object) (object).hl.uint8_values.at_0
|
|
|
|
/** @brief Accesses the most significant byte of the AF' register of a
|
|
* <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_A_(object) (object).af_.uint8_values.at_1
|
|
|
|
/** @brief Accesses the least significant byte of the AF' register of a
|
|
* <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_F_(object) (object).af_.uint8_values.at_0
|
|
|
|
/** @brief Accesses the most significant byte of the BC' register of a
|
|
* <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_B_(object) (object).bc_.uint8_values.at_1
|
|
|
|
/** @brief Accesses the least significant byte of the BC' register of a
|
|
* <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_C_(object) (object).bc_.uint8_values.at_0
|
|
|
|
/** @brief Accesses the most significant byte of the DE' register of a
|
|
* <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_D_(object) (object).de_.uint8_values.at_1
|
|
|
|
/** @brief Accesses the least significant byte of the DE' register of a
|
|
* <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_E_(object) (object).de_.uint8_values.at_0
|
|
|
|
/** @brief Accesses the most significant byte of the HL' register of a
|
|
* <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_H_(object) (object).hl_.uint8_values.at_1
|
|
|
|
/** @brief Accesses the least significant byte of the HL' register of a
|
|
* <tt>@ref Z80</tt> @p object. */
|
|
|
|
#define Z80_L_(object) (object).hl_.uint8_values.at_0
|
|
|
|
#define Z80_WZ Z80_MEMPTR /**< @brief Same as <tt>@ref Z80_MEMPTR</tt>. */
|
|
#define Z80_WZH Z80_MEMPTRH /**< @brief Same as <tt>@ref Z80_MEMPTRH</tt>. */
|
|
#define Z80_WZL Z80_MEMPTRL /**< @brief Same as <tt>@ref Z80_MEMPTRL</tt>. */
|
|
|
|
Z_EXTERN_C_BEGIN
|
|
|
|
/** @brief Sets the power state of a <tt>@ref Z80</tt>.
|
|
*
|
|
* @param self Pointer to the object on which the function is called.
|
|
* @param state
|
|
* @c Z_TRUE = power on;
|
|
* @c Z_FALSE = power off. */
|
|
|
|
Z80_API void z80_power(Z80 *self, zboolean state);
|
|
|
|
/** @brief Performs an instantaneous normal RESET on a <tt>@ref Z80</tt>.
|
|
*
|
|
* @param self Pointer to the object on which the function is called. */
|
|
|
|
Z80_API void z80_instant_reset(Z80 *self);
|
|
|
|
/** @brief Sends a special RESET signal to a <tt>@ref Z80</tt>.
|
|
*
|
|
* @sa
|
|
* - http://www.primrosebank.net/computers/z80/z80_special_reset.htm
|
|
* - US Patent 4486827
|
|
*
|
|
* @param self Pointer to the object on which the function is called. */
|
|
|
|
Z80_API void z80_special_reset(Z80 *self);
|
|
|
|
/** @brief Sets the state of the INT line of a <tt>@ref Z80</tt>.
|
|
*
|
|
* @param self Pointer to the object on which the function is called.
|
|
* @param state
|
|
* @c Z_TRUE = set line low;
|
|
* @c Z_FALSE = set line high. */
|
|
|
|
Z80_API void z80_int(Z80 *self, zboolean state);
|
|
|
|
/** @brief Triggers the NMI line of a <tt>@ref Z80</tt>.
|
|
*
|
|
* @param self Pointer to the object on which the function is called. */
|
|
|
|
Z80_API void z80_nmi(Z80 *self);
|
|
|
|
/** @brief Runs a <tt>@ref Z80</tt> for a given number of clock @p cycles,
|
|
* executing only instructions without responding to signals.
|
|
*
|
|
* @param self Pointer to the object on which the function is called.
|
|
* @param cycles Number of clock cycles to be emulated.
|
|
* @return The actual number of clock cycles emulated. */
|
|
|
|
Z80_API zusize z80_execute(Z80 *self, zusize cycles);
|
|
|
|
/** @brief Runs a <tt>@ref Z80</tt> for a given number of clock @p cycles.
|
|
*
|
|
* @param self Pointer to the object on which the function is called.
|
|
* @param cycles Number of clock cycles to be emulated.
|
|
* @return The actual number of clock cycles emulated. */
|
|
|
|
Z80_API zusize z80_run(Z80 *self, zusize cycles);
|
|
|
|
|
|
/** @brief Ends the emulation loop of <tt>@ref z80_execute</tt> or
|
|
* <tt>@ref z80_run</tt>.
|
|
*
|
|
* This function should only be used inside callback functions. It zeroes
|
|
* <tt>@ref Z80::cycle_limit</tt>, thus breaking the emulation loop after the
|
|
* ongoing emulation step has finished executing.
|
|
*
|
|
* @param self Pointer to the object on which the function is called. */
|
|
|
|
static inline void z80_break(Z80 *self)
|
|
{self->cycle_limit = 0;}
|
|
|
|
|
|
/** @brief Gets the full value of the R register of a <tt>@ref Z80</tt>.
|
|
*
|
|
* @param self Pointer to the object on which the function is called.
|
|
* @return The value of the R register. */
|
|
|
|
static inline zuint8 z80_r(Z80 const *self)
|
|
{return (self->r & 127) | (self->r7 & 128);}
|
|
|
|
|
|
/** @brief Obtains the refresh address of the M1 cycle being executed by a
|
|
* <tt>@ref Z80</tt>.
|
|
*
|
|
* @param self Pointer to the object on which the function is called.
|
|
* @return The refresh address. */
|
|
|
|
static inline zuint16 z80_refresh_address(Z80 const *self)
|
|
{
|
|
return Z_CAST(zuint16)(
|
|
((zuint16)self->i << 8) |
|
|
((self->r - 1) & 127) |
|
|
(self->r7 & 128));
|
|
}
|
|
|
|
|
|
/** @brief Obtains the clock cycle, relative to the start of the instruction, at
|
|
* which the I/O read M-cycle being executed by a <tt>@ref Z80</tt> begins.
|
|
*
|
|
* @param self Pointer to the object on which the function is called.
|
|
* @return The clock cycle at which the I/O read M-cycle begins. */
|
|
|
|
static inline zuint8 z80_in_cycle(Z80 const *self)
|
|
{
|
|
return Z_CAST(zuint8)(self->data.uint8_array[0] == 0xDB
|
|
? /* in a,(BYTE) : 4+3 */
|
|
7
|
|
: /* in J,(c) / in (c) : 4+4 */
|
|
8
|
|
+ /* ini / ind / inir / indr : 4+5 */
|
|
(self->data.uint8_array[1] >> 7));
|
|
}
|
|
|
|
|
|
/** @brief Obtains the clock cycle, relative to the start of the instruction, at
|
|
* which the I/O write M-cycle being executed by a <tt>@ref Z80</tt> begins.
|
|
*
|
|
* @param self Pointer to the object on which the function is called.
|
|
* @return The clock cycle at which the I/O write M-cycle begins. */
|
|
|
|
static inline zuint8 z80_out_cycle(Z80 const *self)
|
|
{
|
|
return Z_CAST(zuint8)(self->data.uint8_array[0] == 0xD3
|
|
? /* out (BYTE),a : 4+3 */
|
|
7
|
|
: /* out (c),J / out (c),0 : 4+4 */
|
|
8
|
|
+ /* outi / outd / otir / otdr : 4+5+3 */
|
|
((self->data.uint8_array[1] >> 7) << 2));
|
|
}
|
|
|
|
|
|
Z_EXTERN_C_END
|
|
|
|
#endif /* Z80_H */
|