Z80 software emulator.

Source:

z80.h:104

Author:

Alessandro Scotti

Version:

1.1

Entity	Type	Scope	Short Description
~Z80	destructor	public	Destructor.
Z80	constructor	public	Copy constructor: creates a copy of the specified Z80 object.
Z80	constructor	public	Constructor: creates a Z80 object with the specified environment.
$anonymous$	enum	public	CPU flags
A	attribute	public	A register (accumulator)
A1	attribute	public	Alternate A register (A')
AF	method	public	Returns the 16 bit register AF.
B	attribute	public	B register
B1	attribute	public	Alternate B register (B')
BC	method	public	Returns the 16 bit register BC.
C	attribute	public	C register
C1	attribute	public	Alternate C register (C')
D	attribute	public	D register
D1	attribute	public	Alternate D register (D')
DE	method	public	Returns the 16 bit register DE.
E	attribute	public	E register
E1	attribute	public	Alternate E register (E')
F	attribute	public	Flags register
F1	attribute	public	Alternate flags register (F')
getCycles	method	public	Returns the number of Z80 CPU cycles elapsed so far.
getInterruptMode	method	public	Returns the current interrupt mode.
getSizeOfSnapshotBuffer	method	public	Returns the size of the buffer needed to take a snapshot of the CPU.
H	attribute	public	H register
H1	attribute	public	Alternate H register (H')
HL	method	public	Returns the 16 bit register HL.
I	attribute	public	Interrupt register
interrupt	method	public	Invokes an interrupt.
isHalted	method	public	Returns non-zero if the CPU is halted, otherwise zero.
IX	attribute	public	Index register X
IY	attribute	public	Index register Y
L	attribute	public	L register
L1	attribute	public	Alternate L register (L')
nmi	method	public	Forces a non-maskable interrupt.
operator =	operator	public	Copies CPU register from one object to another.
PC	attribute	public	Program counter
R	attribute	public	Refresh register
reset	method	public	Resets the CPU to its initial state.
restoreSnapshot	method	public	Restores a snapshot taken with takeSnapshot().
run	method	public	Runs the CPU for the specified number of cycles.
setCycles	method	public	Sets the CPU cycle counter to the specified value.
setInterruptMode	method	public	Sets the interrupt mode to the specified value.
SP	attribute	public	Stack pointer
step	method	public	Executes one instruction.
takeSnapshot	method	public	Takes a snapshot of the CPU.

Destructor.

Source:

z80.h:155

Code:

public virtual ~ Z80 ( )

Copy constructor: creates a copy of the specified Z80 object.

Source:

z80.h:151

Code:

public Z80 (

const Z80 & )

Constructor: creates a Z80 object with the specified environment.

Source:

z80.h:146

Code:

public Z80 (

Z80Environment & )

CPU flags

Source:

z80.h:116

Code:

public enum {	Carry = 0x01 ,
	AddSub = 0x02 ,
	Subtraction = AddSub ,
	Parity = 0x04 ,
	Overflow = Parity ,
	Flag3 = 0x08 ,
	Halfcarry = 0x10 ,
	Flag5 = 0x20 ,
	Zero = 0x40 ,
	Sign = 0x80 }

A register (accumulator)

Source:

z80.h:126

Code:

public unsigned char A

Alternate A register (A')

Source:

z80.h:134

Code:

public unsigned char A1

Returns the 16 bit register AF.

Source:

z80.h:203

Code:

public unsigned AF (

) const

B register

Source:

z80.h:120

Code:

public unsigned char B

Alternate B register (B')

Source:

z80.h:128

Code:

public unsigned char B1

Returns the 16 bit register BC.

Source:

z80.h:208

Code:

public unsigned BC (

) const

C register

Source:

z80.h:121

Code:

public unsigned char C

Alternate C register (C')

Source:

z80.h:129

Code:

public unsigned char C1

D register

Source:

z80.h:122

Code:

public unsigned char D

Alternate D register (D')

Source:

z80.h:130

Code:

public unsigned char D1

Returns the 16 bit register DE.

Source:

z80.h:213

Code:

public unsigned DE (

) const

E register

Source:

z80.h:123

Code:

public unsigned char E

Alternate E register (E')

Source:

z80.h:131

Code:

public unsigned char E1

Flags register

Source:

z80.h:127

Code:

public unsigned char F

Alternate flags register (F')

Source:

z80.h:135

Code:

public unsigned char F1

Returns the number of Z80 CPU cycles elapsed so far.

The cycle count is reset to zero when reset() is called, or it can be set to any value with setCycles(). It is updated after a CPU instruction is executed, for example by calling step() or interrupt().

Source:

z80.h:230

Code:

public unsigned getCycles (

) const

Returns the current interrupt mode.

Source:

z80.h:240

Code:

public unsigned getInterruptMode (

) const

Returns the size of the buffer needed to take a snapshot of the CPU.

Source:

z80.h:258

Code:

public unsigned getSizeOfSnapshotBuffer (

) const

H register

Source:

z80.h:124

Code:

public unsigned char H

Alternate H register (H')

Source:

z80.h:132

Code:

public unsigned char H1

Returns the 16 bit register HL.

Source:

z80.h:218

Code:

public unsigned HL (

) const

Interrupt register

Source:

z80.h:140

Code:

public unsigned char I

Invokes an interrupt.

If interrupts are enabled, the current program counter (PC) is saved on the stack and assigned the specified address. When the interrupt handler returns, execution resumes from the point where the interrupt occurred.

The actual interrupt address depends on the current interrupt mode and on the interrupt type. For maskable interrupts, data is as follows: - mode 0: data is an opcode that is executed (usually RST xxh); - mode 1: data is ignored and a call is made to address 0x38; - mode 2: a call is made to the 16 bit address given by (256*I + data).

Source:

z80.h:195

Code:

public void interrupt (

unsigned char data )

Returns non-zero if the CPU is halted, otherwise zero.

Source:

z80.h:248

Code:

public int isHalted (

) const

Index register X

Source:

z80.h:136

Code:

public unsigned IX

Index register Y

Source:

z80.h:137

Code:

public unsigned IY

L register

Source:

z80.h:125

Code:

public unsigned char L

Alternate L register (L')

Source:

z80.h:133

Code:

public unsigned char L1

Forces a non-maskable interrupt.

Source:

z80.h:198

Code:

public void nmi (

)

Copies CPU register from one object to another.

Note that the environment is not copied, only registers.

Source:

z80.h:255

Code:

public Z80 & operator = (

const Z80 & )

Program counter

Source:

z80.h:138

Code:

public unsigned PC

Refresh register

Source:

z80.h:141

Code:

public unsigned char R

Resets the CPU to its initial state.

The stack pointer (SP) is set to F000h, all other registers are cleared.

Source:

z80.h:162

Code:

public virtual void reset (

)

Restores a snapshot taken with takeSnapshot().

This function uses the data saved in the snapshot buffer to restore the CPU status.

Source:

z80.h:286

Param:

buffer

buffer where the snapshot data is stored

Returns:

the number of bytes read from the buffer

Code:

public unsigned restoreSnapshot (

unsigned char * buffer )

Runs the CPU for the specified number of cycles.

Note that the number of CPU cycles performed by this function may be actually a little more than the value specified. If that happens then the function returns the number of extra cycles executed.

Source:

z80.h:175

Param:

cycles

number of cycles the CPU must execute

Returns:

the number of extra cycles executed by the last instruction

Code:

public virtual unsigned run (

unsigned cycles )

Sets the CPU cycle counter to the specified value.

Source:

z80.h:235

Code:

public void setCycles (

unsigned value )

Sets the interrupt mode to the specified value.

Source:

z80.h:243

Code:

public void setInterruptMode (

unsigned mode )

Stack pointer

Source:

z80.h:139

Code:

public unsigned SP

Executes one instruction.

Source:

z80.h:180

Code:

public virtual void step (

)

Takes a snapshot of the CPU.

A snapshot saves all of the CPU registers and internals. It can be restored at any time to bring the CPU back to the exact status it had when the snapshot was taken.

Note: the size of the snapshot buffer must be no less than the size returned by the getSizeOfSnapshotBuffer() function.

Source:

z80.h:274

Param:

buffer

buffer where the snapshot data is stored

Returns:

the number of bytes written into the buffer

Code:

public unsigned takeSnapshot (

unsigned char * buffer )

Copyright (c) 1997-2003,2004 Alessandro Scotti. All rights reserved.