Changed interface so that Z80 registers are exposed publicly -- using a

Set/Get interface was too ponderous for emulation needs.

7 files changed, 310 insertions, 427 deletions

diff --git a/emma.c b/emma.c
index 89a70de..a719885 100644
--- a/emma.c
+++ b/emma.c
@@ -207,17 +207,19 @@ static const char *FlagString(Z80Byte flag)
 
 static void DisplayState(void)
 {
-    Z80State s;
-
-    Z80GetState(z80,&s);
-
-    Log("A=%2.2x  F=%s  ",s.AF>>8,FlagString(s.AF&0xff));
-    Log("BC=%4.4x  DE=%4.4x  HL=%4.4x  ",s.BC,s.DE,s.HL);
-    Log("IX=%4.4x  IY=%4.4x  SP=%4.4x\n",s.IX,s.IY,s.SP);
-    Log("I=%2.2x  IM=%2.2x  R=%2.2x  ",s.I,s.IM,s.R);
-    Log("IFF1=%2.2x  IFF2=%2.2x  CYCLES=%lu\n",s.IFF1,s.IFF2,s.cycle);
-    Log("%4.4x: ",s.PC);
-    Log("%s\n",Disassemble(&s.PC));
+    Z80Word pc;
+
+    pc=z80->PC;
+
+    Log("A=%2.2x  F=%s  ",
+		z80->AF.b[Z80_HI_WORD],FlagString(z80->AF.b[Z80_LO_WORD]));
+    Log("BC=%4.4x  DE=%4.4x  HL=%4.4x  ",z80->BC.w,z80->DE.w,z80->HL.w);
+    Log("IX=%4.4x  IY=%4.4x  SP=%4.4x\n",z80->IX.w,z80->IY.w,z80->SP);
+    Log("I=%2.2x  IM=%2.2x  R=%2.2x  ",z80->I,z80->IM,z80->R);
+    Log("IFF1=%2.2x  IFF2=%2.2x  CYCLES=%lu\n",
+    		z80->IFF1,z80->IFF2,Z80Cycles(z80));
+    Log("%4.4x: ",pc);
+    Log("%s\n",Disassemble(&pc));
 }
 
 
@@ -238,75 +240,72 @@ static int StrEq(const char *a, const char *b)
 
 static int Expand(void *client, const char *p, long *res)
 {
-    Z80State s;
     int ok=TRUE;
 
-    Z80GetState(z80,&s);
-
     if (StrEq(p,"AF"))
-    	*res=s.AF;
+    	*res=z80->AF.w;
     else if (StrEq(p,"BC"))
-    	*res=s.BC;
+    	*res=z80->BC.w;
     else if (StrEq(p,"DE"))
-    	*res=s.DE;
+    	*res=z80->DE.w;
     else if (StrEq(p,"HL"))
-    	*res=s.HL;
+    	*res=z80->HL.w;
     else if (StrEq(p,"IX"))
-    	*res=s.IX;
+    	*res=z80->IX.w;
     else if (StrEq(p,"IY"))
-    	*res=s.IY;
+    	*res=z80->IY.w;
     else if (StrEq(p,"SP"))
-    	*res=s.SP;
+    	*res=z80->SP;
     else if (StrEq(p,"PC"))
-    	*res=s.PC;
+    	*res=z80->PC;
     else if (StrEq(p,"A"))
-    	*res=HI(s.AF);
+    	*res=HI(z80->AF.w);
     else if (StrEq(p,"F"))
-    	*res=LO(s.AF);
+    	*res=LO(z80->AF.w);
     else if (StrEq(p,"B"))
-    	*res=HI(s.BC);
+    	*res=HI(z80->BC.w);
     else if (StrEq(p,"C"))
-    	*res=LO(s.BC);
+    	*res=LO(z80->BC.w);
     else if (StrEq(p,"D"))
-    	*res=HI(s.DE);
+    	*res=HI(z80->DE.w);
     else if (StrEq(p,"E"))
-    	*res=LO(s.DE);
+    	*res=LO(z80->DE.w);
     else if (StrEq(p,"H"))
-    	*res=HI(s.HL);
+    	*res=HI(z80->HL.w);
     else if (StrEq(p,"L"))
-    	*res=LO(s.HL);
+    	*res=LO(z80->HL.w);
     else if (StrEq(p,"AF_"))
-    	*res=s.AF_;
+    	*res=z80->AF_;
     else if (StrEq(p,"BC_"))
-    	*res=s.BC_;
+    	*res=z80->BC_;
     else if (StrEq(p,"DE_"))
-    	*res=s.DE_;
+    	*res=z80->DE_;
     else if (StrEq(p,"HL_"))
-    	*res=s.HL_;
+    	*res=z80->HL_;
     else if (StrEq(p,"A_"))
-    	*res=HI(s.AF_);
+    	*res=HI(z80->AF_);
     else if (StrEq(p,"F_"))
-    	*res=LO(s.AF_);
+    	*res=LO(z80->AF_);
     else if (StrEq(p,"B_"))
-    	*res=HI(s.BC_);
+    	*res=HI(z80->BC_);
     else if (StrEq(p,"C_"))
-    	*res=LO(s.BC_);
+    	*res=LO(z80->BC_);
     else if (StrEq(p,"D_"))
-    	*res=HI(s.DE_);
+    	*res=HI(z80->DE_);
     else if (StrEq(p,"E_"))
-    	*res=LO(s.DE_);
+    	*res=LO(z80->DE_);
     else if (StrEq(p,"H_"))
-    	*res=HI(s.HL_);
+    	*res=HI(z80->HL_);
     else if (StrEq(p,"L_"))
-	*res=LO(s.HL_);
+	*res=LO(z80->HL_);
     else if (StrEq(p,"IM"))
-	*res=s.IM;
+	*res=z80->IM;
     else if (StrEq(p,"R"))
-	*res=s.R;
+	*res=z80->R;
     else if (StrEq(p,"IFF1"))
-	*res=s.IFF1;
+	*res=z80->IFF1;
     else if (StrEq(p,"IFF2"))
-	*res=s.IFF2;
+	*res=z80->IFF2;
     else if (p[0]=='@')
     {
 	Z80Word n;
@@ -709,20 +708,14 @@ static void DoStep(int no, const char *arg[])
 
 static void DoSetPC(int no, const char *arg[])
 {
-    Z80State s;
-
-    Z80GetState(z80,&s);
-
     if (no<2)
     {
-    	s.PC=MK(Z80_MEMORY[s.SP+1],Z80_MEMORY[s.SP]);
-	s.SP+=2;
+    	z80->PC=MK(Z80_MEMORY[z80->SP+1],Z80_MEMORY[z80->SP]);
+	z80->SP+=2;
 	DisplayState();
     }
     else
-	s.PC=Address(arg[1]);
-
-    Z80SetState(z80,&s);
+	z80->PC=Address(arg[1]);
 }
 
 
@@ -730,11 +723,7 @@ static void DoRun(int no, const char *arg[])
 {
     if (no>1)
     {
-    	Z80State s;
-
-	Z80GetState(z80,&s);
-	s.PC=Address(arg[1]);
-	Z80SetState(z80,&s);
+	z80->PC=Address(arg[1]);
     }
 
     while(!stop)
@@ -766,11 +755,7 @@ static void DoUntil(int no, const char *arg[])
 
     if (no>2)
     {
-    	Z80State s;
-
-	Z80GetState(z80,&s);
-	s.PC=Address(arg[2]);
-	Z80SetState(z80,&s);
+	z80->PC=Address(arg[2]);
     }
 
     while(!stop)
@@ -976,12 +961,9 @@ static Z80Byte ReadPort(Z80 *z80, Z80Word addr)
 {
     Z80Byte b=0xff;
     Z80Word ptr;
-    Z80State s;
     char expr[1024];
     char *p;
 
-    Z80GetState(z80,&s);
-
     switch(addr&0xff)
     {
     	case 0x80:
@@ -1001,7 +983,7 @@ static Z80Byte ReadPort(Z80 *z80, Z80Word addr)
 	    break;
 
     	case 0x81:
-	    ptr=s.DE;
+	    ptr=z80->DE.w;
 
 	    p=expr;
 
@@ -1025,9 +1007,9 @@ static Z80Byte ReadPort(Z80 *z80, Z80Word addr)
 
 static void WritePort(Z80 *z80, Z80Word addr, Z80Byte val)
 {
-    Z80State s;
+    Z80Word de;
 
-    Z80GetState(z80,&s);
+    de=z80->DE.w;
 
     switch(addr&0xff)
     {
@@ -1042,21 +1024,22 @@ static void WritePort(Z80 *z80, Z80Word addr, Z80Byte val)
 	    break;
 
     	case 0x82:
-	    while(Z80_MEMORY[s.DE]!='$')
+	    while(Z80_MEMORY[de]!='$')
 	    {
-		if (isspace(Z80_MEMORY[s.DE]) || isprint(Z80_MEMORY[s.DE]))
-		    Log("%c",Z80_MEMORY[s.DE]);
+		if (isspace(Z80_MEMORY[de]) ||
+			isprint(Z80_MEMORY[de]))
+		    Log("%c",Z80_MEMORY[de]);
 
-		s.DE++;
+		de++;
 	    }
 	    fflush(stdout);
 	    break;
 
     	case 0x83:
-	    while(Z80_MEMORY[s.DE])
+	    while(Z80_MEMORY[de])
 	    {
-		Log("%c",Z80_MEMORY[s.DE]);
-		s.DE++;
+		Log("%c",Z80_MEMORY[de]);
+		de++;
 	    }
 	    fflush(stdout);
 	    break;
diff --git a/gemma.c b/gemma.c
index c0fcf43..ec05b5d 100644
--- a/gemma.c
+++ b/gemma.c
@@ -93,7 +93,7 @@ static Z80Word Get_PC(int back)
 
 static void Step(void)
 {
-    pc_buffer[pc_head]=Z80GetPC(z80);
+    pc_buffer[pc_head]=z80->PC;
 
     if (pc_head)
     	pc_head--;
@@ -197,75 +197,72 @@ static int StrEq(const char *a, const char *b)
 
 static int Expand(void *client, const char *p, long *res)
 {
-    Z80State s;
     int ok=TRUE;
 
-    Z80GetState(z80,&s);
-
     if (StrEq(p,"AF"))
-    	*res=s.AF;
+    	*res=z80->AF.w;
     else if (StrEq(p,"BC"))
-    	*res=s.BC;
+    	*res=z80->BC.w;
     else if (StrEq(p,"DE"))
-    	*res=s.DE;
+    	*res=z80->DE.w;
     else if (StrEq(p,"HL"))
-    	*res=s.HL;
+    	*res=z80->HL.w;
     else if (StrEq(p,"IX"))
-    	*res=s.IX;
+    	*res=z80->IX.w;
     else if (StrEq(p,"IY"))
-    	*res=s.IY;
+    	*res=z80->IY.w;
     else if (StrEq(p,"SP"))
-    	*res=s.SP;
+    	*res=z80->SP;
     else if (StrEq(p,"PC"))
-    	*res=s.PC;
+    	*res=z80->PC;
     else if (StrEq(p,"A"))
-    	*res=HI(s.AF);
+    	*res=HI(z80->AF.w);
     else if (StrEq(p,"F"))
-    	*res=LO(s.AF);
+    	*res=LO(z80->AF.w);
     else if (StrEq(p,"B"))
-    	*res=HI(s.BC);
+    	*res=HI(z80->BC.w);
     else if (StrEq(p,"C"))
-    	*res=LO(s.BC);
+    	*res=LO(z80->BC.w);
     else if (StrEq(p,"D"))
-    	*res=HI(s.DE);
+    	*res=HI(z80->DE.w);
     else if (StrEq(p,"E"))
-    	*res=LO(s.DE);
+    	*res=LO(z80->DE.w);
     else if (StrEq(p,"H"))
-    	*res=HI(s.HL);
+    	*res=HI(z80->HL.w);
     else if (StrEq(p,"L"))
-    	*res=LO(s.HL);
+    	*res=LO(z80->HL.w);
     else if (StrEq(p,"AF_"))
-    	*res=s.AF_;
+    	*res=z80->AF_;
     else if (StrEq(p,"BC_"))
-    	*res=s.BC_;
+    	*res=z80->BC_;
     else if (StrEq(p,"DE_"))
-    	*res=s.DE_;
+    	*res=z80->DE_;
     else if (StrEq(p,"HL_"))
-    	*res=s.HL_;
+    	*res=z80->HL_;
     else if (StrEq(p,"A_"))
-    	*res=HI(s.AF_);
+    	*res=HI(z80->AF_);
     else if (StrEq(p,"F_"))
-    	*res=LO(s.AF_);
+    	*res=LO(z80->AF_);
     else if (StrEq(p,"B_"))
-    	*res=HI(s.BC_);
+    	*res=HI(z80->BC_);
     else if (StrEq(p,"C_"))
-    	*res=LO(s.BC_);
+    	*res=LO(z80->BC_);
     else if (StrEq(p,"D_"))
-    	*res=HI(s.DE_);
+    	*res=HI(z80->DE_);
     else if (StrEq(p,"E_"))
-    	*res=LO(s.DE_);
+    	*res=LO(z80->DE_);
     else if (StrEq(p,"H_"))
-    	*res=HI(s.HL_);
+    	*res=HI(z80->HL_);
     else if (StrEq(p,"L_"))
-	*res=LO(s.HL_);
+	*res=LO(z80->HL_);
     else if (StrEq(p,"IM"))
-	*res=s.IM;
+	*res=z80->IM;
     else if (StrEq(p,"R"))
-	*res=s.R;
+	*res=z80->R;
     else if (StrEq(p,"IFF1"))
-	*res=s.IFF1;
+	*res=z80->IFF1;
     else if (StrEq(p,"IFF2"))
-	*res=s.IFF2;
+	*res=z80->IFF2;
     else if (p[0]=='@')
     {
 	Z80Word n;
@@ -428,12 +425,9 @@ static Z80Byte ReadPort(Z80 *z80, Z80Word addr)
 {
     Z80Byte b=0xff;
     Z80Word ptr;
-    Z80State s;
     char expr[1024];
     char *p;
 
-    Z80GetState(z80,&s);
-
     switch(addr&0xff)
     {
     	case 0x80:
@@ -453,7 +447,7 @@ static Z80Byte ReadPort(Z80 *z80, Z80Word addr)
 	    break;
 
     	case 0x81:
-	    ptr=s.DE;
+	    ptr=z80->DE.w;
 
 	    p=expr;
 
@@ -477,50 +471,47 @@ static Z80Byte ReadPort(Z80 *z80, Z80Word addr)
 
 static void WritePort(Z80 *z80, Z80Word addr, Z80Byte val)
 {
-    Z80State s;
-    DString ds;
+    Z80Word de;
 
-    ds=DSInit();
-    Z80GetState(z80,&s);
+    de=z80->DE.w;
 
     switch(addr&0xff)
     {
     	case 0x80:
-	    DSAddChar(ds,val);
+	    Log("%c",val);
+	    fflush(stdout);
 	    break;
 
 	case 0x81:
-	    DSAdd(ds,"Stop requested via OUT(0x81)\n");
+	    Log("Stop requested\n");
 	    stop=TRUE;
 	    break;
 
     	case 0x82:
-	    while(Z80_MEMORY[s.DE]!='$')
+	    while(Z80_MEMORY[de]!='$')
 	    {
-		if (isspace(Z80_MEMORY[s.DE]) || isprint(Z80_MEMORY[s.DE]))
-		{
-		    DSAddChar(ds,Z80_MEMORY[s.DE]);
-		}
+		if (isspace(Z80_MEMORY[de]) ||
+			isprint(Z80_MEMORY[de]))
+		    Log("%c",Z80_MEMORY[de]);
 
-		s.DE++;
+		de++;
 	    }
+	    fflush(stdout);
 	    break;
 
     	case 0x83:
-	    while(Z80_MEMORY[s.DE])
+	    while(Z80_MEMORY[de])
 	    {
-		DSAddChar(ds,Z80_MEMORY[s.DE]);
-		s.DE++;
+		Log("%c",Z80_MEMORY[de]);
+		de++;
 	    }
+	    fflush(stdout);
 	    break;
 
 	default:
 	    Log("Wrote 0x%2.2x to port 0x%4.4x\n",(int)val,(int)addr);
-	    return;
+	    break;
     }
-
-    Log(ds->text);
-    DSFree(ds);
 }
 
 
@@ -538,10 +529,6 @@ static int Halt(Z80 *z80, Z80Val v)
 */
 void GEMMA_UpdateDisplay(GEMMA_View view)
 {
-    Z80State reg;
-
-    Z80GetState(z80,&reg);
-
     if (view&UPDATE_ASSEM_VIEW)
     {
 	Z80Word pc;
@@ -562,7 +549,7 @@ void GEMMA_UpdateDisplay(GEMMA_View view)
 	    DSAddChar(ds,'\n');
 	}
 
-	pc=Z80GetPC(z80);
+	pc=z80->PC;
 
 	for(f=0;f<12;f++)
 	{
@@ -593,65 +580,65 @@ void GEMMA_UpdateDisplay(GEMMA_View view)
     if (view&UPDATE_REG_VIEW)
     {
 	static int reg_once=FALSE;
-	static Z80State last_reg;
+	static Z80 last_reg;
 	DString ds;
 
 	ds=DSInit();
 
 	if (!reg_once)
 	{
-	    last_reg=reg;
+	    last_reg=*z80;
 	    reg_once=TRUE;
 	}
 
 	DSAdd(ds,"<tt>");
 
-	DisplayState(ds,"A  ",2,HI(reg.AF),HI(last_reg.AF));
+	DisplayState(ds,"A  ",2,HI(z80->AF.w),HI(last_reg.AF.w));
 	DSAdd(ds,"    ");
-	FlagString(ds,LO(reg.AF),LO(last_reg.AF));
+	FlagString(ds,LO(z80->AF.w),LO(last_reg.AF.w));
 	DSAdd(ds,"\n");
 
-	DisplayState(ds,"BC ",4,reg.BC,last_reg.BC);
+	DisplayState(ds,"BC ",4,z80->BC.w,last_reg.BC.w);
 	DSAdd(ds,"    ");
-	DisplayState(ds,"DE ",4,reg.DE,last_reg.DE);
+	DisplayState(ds,"DE ",4,z80->DE.w,last_reg.DE.w);
 	DSAdd(ds,"    ");
-	DisplayState(ds,"HL ",4,reg.HL,last_reg.HL);
+	DisplayState(ds,"HL ",4,z80->HL.w,last_reg.HL.w);
 	DSAdd(ds,"\n");
 
-	DisplayState(ds,"SP ",4,reg.SP,last_reg.SP);
+	DisplayState(ds,"SP ",4,z80->SP,last_reg.SP);
 	DSAdd(ds,"    ");
-	DisplayState(ds,"IX ",4,reg.IX,last_reg.IX);
+	DisplayState(ds,"IX ",4,z80->IX.w,last_reg.IX.w);
 	DSAdd(ds,"    ");
-	DisplayState(ds,"IY ",4,reg.IY,last_reg.IY);
+	DisplayState(ds,"IY ",4,z80->IY.w,last_reg.IY.w);
 	DSAdd(ds,"\n\n");
 
-	DisplayState(ds,"A' ",2,HI(reg.AF_),HI(last_reg.AF_));
+	DisplayState(ds,"A' ",2,HI(z80->AF_),HI(last_reg.AF_));
 	DSAdd(ds,"    ");
-	FlagString(ds,LO(reg.AF_),LO(last_reg.AF_));
+	FlagString(ds,LO(z80->AF_),LO(last_reg.AF_));
 	DSAdd(ds,"\n");
 
-	DisplayState(ds,"BC'",4,reg.BC_,last_reg.BC_);
+	DisplayState(ds,"BC'",4,z80->BC_,last_reg.BC_);
 	DSAdd(ds,"    ");
-	DisplayState(ds,"DE'",4,reg.DE_,last_reg.DE_);
+	DisplayState(ds,"DE'",4,z80->DE_,last_reg.DE_);
 	DSAdd(ds,"    ");
-	DisplayState(ds,"HL'",4,reg.HL_,last_reg.HL_);
+	DisplayState(ds,"HL'",4,z80->HL_,last_reg.HL_);
 	DSAdd(ds,"\n\n");
 
-	DisplayState(ds,"PC ",4,reg.PC,last_reg.PC);
+	DisplayState(ds,"PC ",4,z80->PC,last_reg.PC);
 	DSAdd(ds,"  ");
-	DisplayState(ds,"CYCLE",8,reg.cycle,last_reg.cycle);
+	DisplayState(ds,"CYCLE",8,Z80Cycles(z80),0);
 	DSAdd(ds,"\n\n");
 
-	DisplayState(ds,"R  ",2,reg.R,last_reg.R);
+	DisplayState(ds,"R  ",2,z80->R,last_reg.R);
 	DSAdd(ds,"     ");
-	DisplayState(ds,"IFF1",1,reg.IFF1,last_reg.IFF1);
+	DisplayState(ds,"IFF1",1,z80->IFF1,last_reg.IFF1);
 	DSAdd(ds,"      ");
-	DisplayState(ds,"IFF2",1,reg.IFF2,last_reg.IFF2);
+	DisplayState(ds,"IFF2",1,z80->IFF2,last_reg.IFF2);
 	DSAdd(ds,"\n");
 
-	DisplayState(ds,"IM ",1,reg.IM,last_reg.IM);
+	DisplayState(ds,"IM ",1,z80->IM,last_reg.IM);
 	DSAdd(ds,"         ");
-	DisplayState(ds,"I",1,reg.I,last_reg.I);
+	DisplayState(ds,"I",1,z80->I,last_reg.I);
 	DSAdd(ds,"\n");
 
 	DSAdd(ds,"</tt>");
@@ -660,7 +647,7 @@ void GEMMA_UpdateDisplay(GEMMA_View view)
 
 	DSFree(ds);
 
-	last_reg=reg;
+	last_reg=*z80;
     }
 
     if (view&UPDATE_MEM_VIEW)
@@ -678,26 +665,26 @@ void GEMMA_UpdateDisplay(GEMMA_View view)
 	switch(gtk_combo_box_get_active(GTK_COMBO_BOX(memview_combo)))
 	{
 	    case 0:
-		addr=reg.HL;
+		addr=z80->HL.w;
 	    	break;
 	    case 1:
-		addr=reg.SP;
+		addr=z80->SP;
 		as_words=TRUE;
 	    	break;
 	    case 2:
-		addr=reg.IX;
+		addr=z80->IX.w;
 	    	break;
 	    case 3:
-		addr=reg.IY;
+		addr=z80->IY.w;
 	    	break;
 	    case 4:
-		addr=reg.BC;
+		addr=z80->BC.w;
 	    	break;
 	    case 5:
-		addr=reg.DE;
+		addr=z80->DE.w;
 	    	break;
 	    default:
-		addr=reg.PC;
+		addr=z80->PC;
 	    	break;
 	}
 
@@ -896,20 +883,17 @@ void GEMMA_Step(void)
 void GEMMA_StepOver(void)
 {
     Z80Word next;
-    Z80State reg;
 
     stop=FALSE;
 
-    Z80GetState(z80,&reg);
-    next=reg.PC;
+    next=z80->PC;
     Z80Disassemble(z80,&next);
 
     RUNNING(TRUE);
 
-    while(reg.PC!=next && !stop)
+    while(z80->PC!=next && !stop)
     {
 	Step();
-	Z80GetState(z80,&reg);
 	gtk_main_iteration_do(FALSE);
     }
 
@@ -986,7 +970,7 @@ void GEMMA_Init(GtkWidget *top)
 #else
     z80=Z80Init(Peek,Poke,ReadPort,WritePort,Peek);
 #endif
-    Z80SetPC(z80,0x100);
+    z80->PC=0x100;
 
     if (!z80)
     {
diff --git a/z80.c b/z80.c
index 3a15a22..be50494 100644
--- a/z80.c
+++ b/z80.c
@@ -55,28 +55,28 @@ static void Z80_CheckInterrupt(Z80 *cpu)
 {
     /* Check interrupts
     */
-    if (cpu->raise)
+    if (PRIV->raise)
     {
-    	if (cpu->nmi)
+    	if (PRIV->nmi)
 	{
-	    if (cpu->halt)
+	    if (PRIV->halt)
 	    {
-		cpu->halt=FALSE;
+		PRIV->halt=FALSE;
 		CALLBACK(eZ80_Halt,0);
 		cpu->PC++;
 	    }
 
 	    TSTATE(2);
 	    cpu->IFF1=0;
-	    cpu->nmi=FALSE;
+	    PRIV->nmi=FALSE;
 	    PUSH(cpu->PC);
 	    cpu->PC=0x66;
 	}
     	else if (cpu->IFF1)
 	{
-	    if (cpu->halt)
+	    if (PRIV->halt)
 	    {
-		cpu->halt=FALSE;
+		PRIV->halt=FALSE;
 		CALLBACK(eZ80_Halt,0);
 		cpu->PC++;
 	    }
@@ -88,7 +88,7 @@ static void Z80_CheckInterrupt(Z80 *cpu)
 		default:
 		case 0:
 		    INC_R;
-		    Z80_Decode(cpu,cpu->devbyte);
+		    Z80_Decode(cpu,PRIV->devbyte);
 		    return;
 		    break;
 
@@ -99,12 +99,12 @@ static void Z80_CheckInterrupt(Z80 *cpu)
 
 		case 2:
 		    PUSH(cpu->PC);
-		    cpu->PC=(Z80Word)cpu->I*256+cpu->devbyte;
+		    cpu->PC=(Z80Word)cpu->I*256+PRIV->devbyte;
 		    break;
 	    }
 	}
 
-	cpu->raise=FALSE;
+	PRIV->raise=FALSE;
     }
 }
 
@@ -138,19 +138,29 @@ Z80     *Z80Init(Z80ReadMemory read_memory,
 
     if (cpu)
     {
+    	cpu->priv=malloc(sizeof *cpu->priv);
+
+	if (cpu->priv)
+	{
 #ifndef ENABLE_ARRAY_MEMORY
-	cpu->mread=read_memory;
-	cpu->mwrite=write_memory;
-	cpu->disread=read_for_disassem;
+	    PRIV->mread=read_memory;
+	    PRIV->mwrite=write_memory;
+	    PRIV->disread=read_for_disassem;
 #endif
-	cpu->pread=read_port;
-	cpu->pwrite=write_port;
+	    PRIV->pread=read_port;
+	    PRIV->pwrite=write_port;
 
-	for(f=0;f<eZ80_NO_CALLBACK;f++)
-	    for(r=0;r<MAX_PER_CALLBACK;r++)
-		cpu->callback[f][r]=NULL;
+	    for(f=0;f<eZ80_NO_CALLBACK;f++)
+		for(r=0;r<MAX_PER_CALLBACK;r++)
+		    PRIV->callback[f][r]=NULL;
 
-	Z80Reset(cpu);
+	    Z80Reset(cpu);
+	}
+	else
+	{
+	    free(cpu);
+	    cpu=NULL;
+	}
     }
 
     return cpu;
@@ -159,7 +169,7 @@ Z80     *Z80Init(Z80ReadMemory read_memory,
 
 void Z80Reset(Z80 *cpu)
 {
-    cpu->cycle=0;
+    PRIV->cycle=0;
     cpu->PC=0;
 
     cpu->AF.w=0xffff;
@@ -180,28 +190,22 @@ void Z80Reset(Z80 *cpu)
     cpu->IM=0;
     cpu->I=0;
     cpu->R=0;
-    cpu->halt=0;
+    PRIV->halt=0;
 
-    cpu->raise=FALSE;
-    cpu->nmi=FALSE;
+    PRIV->raise=FALSE;
+    PRIV->nmi=FALSE;
 }
 
 
-void Z80SetPC(Z80 *cpu,Z80Word PC)
-{
-    cpu->PC=PC;
-}
-
-
-Z80Word Z80GetPC(Z80 *cpu)
+Z80Val Z80Cycles(Z80 *cpu)
 {
-    return cpu->PC;
+    return PRIV->cycle;
 }
 
 
 void Z80ResetCycles(Z80 *cpu, Z80Val cycles)
 {
-    cpu->cycle=cycles;
+    PRIV->cycle=cycles;
 }
 
 
@@ -211,9 +215,9 @@ int Z80LodgeCallback(Z80 *cpu, Z80CallbackReason reason, Z80Callback callback)
 
     for(f=0;f<MAX_PER_CALLBACK;f++)
     {
-    	if (!cpu->callback[reason][f])
+    	if (!PRIV->callback[reason][f])
 	{
-	    cpu->callback[reason][f]=callback;
+	    PRIV->callback[reason][f]=callback;
 	    return TRUE;
 	}
     }
@@ -227,23 +231,27 @@ void Z80RemoveCallback(Z80 *cpu, Z80CallbackReason reason, Z80Callback callback)
     int f;
 
     for(f=0;f<MAX_PER_CALLBACK;f++)
-    	if (cpu->callback[reason][f]==callback)
-	    cpu->callback[reason][f]=NULL;
+    {
+    	if (PRIV->callback[reason][f]==callback)
+	{
+	    PRIV->callback[reason][f]=NULL;
+	}
+    }
 }
 
 
 void Z80Interrupt(Z80 *cpu, Z80Byte devbyte)
 {
-    cpu->raise=TRUE;
-    cpu->devbyte=devbyte;
-    cpu->nmi=FALSE;
+    PRIV->raise=TRUE;
+    PRIV->devbyte=devbyte;
+    PRIV->nmi=FALSE;
 }
 
 
 void Z80NMI(Z80 *cpu)
 {
-    cpu->raise=TRUE;
-    cpu->nmi=TRUE;
+    PRIV->raise=TRUE;
+    PRIV->nmi=TRUE;
 }
 
 
@@ -251,12 +259,12 @@ int Z80SingleStep(Z80 *cpu)
 {
     Z80Byte opcode;
 
-    cpu->last_cb=TRUE;
-    cpu->shift=0;
+    PRIV->last_cb=TRUE;
+    PRIV->shift=0;
 
     Z80_CheckInterrupt(cpu);
 
-    CALLBACK(eZ80_Instruction,cpu->cycle);
+    CALLBACK(eZ80_Instruction,PRIV->cycle);
 
     INC_R;
 
@@ -264,7 +272,7 @@ int Z80SingleStep(Z80 *cpu)
 
     Z80_Decode(cpu,opcode);
 
-    return cpu->last_cb;
+    return PRIV->last_cb;
 }
 
 
@@ -274,68 +282,6 @@ void Z80Exec(Z80 *cpu)
 }
 
 
-void Z80GetState(Z80 *cpu, Z80State *state)
-{
-    state->cycle=	cpu->cycle;
-
-    state->AF	=	cpu->AF.w;
-    state->BC	=	cpu->BC.w;
-    state->DE	=	cpu->DE.w;
-    state->HL	=	cpu->HL.w;
-
-    state->AF_	=	cpu->AF_;
-    state->BC_	=	cpu->BC_;
-    state->DE_	=	cpu->DE_;
-    state->HL_	=	cpu->HL_;
-
-    state->IX	=	cpu->IX.w;
-    state->IY	=	cpu->IY.w;
-
-    state->SP	=	cpu->SP;
-    state->PC	=	cpu->PC;
-
-    state->IFF1	=	cpu->IFF1;
-    state->IFF2	=	cpu->IFF2;
-    state->IM	=	cpu->IM;
-    state->I	=	cpu->I;
-    state->R	=	cpu->R;
-}
-
-
-void Z80SetState(Z80 *cpu, const Z80State *state)
-{
-    cpu->cycle	=	state->cycle;
-
-    cpu->AF.w	=	state->AF;
-    cpu->BC.w	=	state->BC;
-    cpu->DE.w	=	state->DE;
-    cpu->HL.w	=	state->HL;
-
-    cpu->AF_	=	state->AF_;
-    cpu->BC_	=	state->BC_;
-    cpu->DE_	=	state->DE_;
-    cpu->HL_	=	state->HL_;
-
-    cpu->IX.w	=	state->IX;
-    cpu->IY.w	=	state->IY;
-
-    cpu->SP	=	state->SP;
-    cpu->PC	=	state->PC;
-
-    cpu->IFF1	=	state->IFF1;
-    cpu->IFF2	=	state->IFF2;
-    cpu->IM	=	state->IM;
-    cpu->I	=	state->I;
-    cpu->R	=	state->R;
-}
-
-
-Z80Val Z80Cycles(Z80 *cpu)
-{
-    return cpu->cycle;
-}
-
-
 void Z80SetLabels(Z80Label labels[])
 {
     z80_labels=labels;
@@ -364,7 +310,7 @@ const char *Z80Disassemble(Z80 *cpu, Z80Word *pc)
 #ifdef ENABLE_ARRAY_MEMORY
 	strcat(s,Z80_Dis_Printf(" %.2x",(int)Z80_MEMORY[opc++]));
 #else
-	strcat(s,Z80_Dis_Printf(" %.2x",(int)cpu->disread(cpu,opc++)));
+	strcat(s,Z80_Dis_Printf(" %.2x",(int)PRIV->disread(cpu,opc++)));
 #endif
     }
 
diff --git a/z80.h b/z80.h
index f6bc041..000b950 100644
--- a/z80.h
+++ b/z80.h
@@ -35,12 +35,6 @@
 /* ---------------------------------------- TYPES
 */
 
-/* The processor
-*/
-struct Z80;
-typedef struct Z80 Z80;
-
-
 /* Large unsigned type
 */
 typedef unsigned long Z80Val;
@@ -61,6 +55,53 @@ typedef signed char Z80Relative;
 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);
@@ -100,36 +141,6 @@ typedef enum
 } Z80CallbackReason;
 
 
-/* Get/settable state of the Z80
-*/
-typedef struct
-{
-    Z80Word	PC;
-    Z80Word	SP;
-
-    Z80Val	cycle;
-
-    Z80Word	AF;
-    Z80Word	BC;
-    Z80Word	DE;
-    Z80Word	HL;
-
-    Z80Word	AF_;	/* Alternate registers */
-    Z80Word	BC_;
-    Z80Word	DE_;
-    Z80Word	HL_;
-
-    Z80Word	IX;
-    Z80Word	IY;
-
-    Z80Byte	IFF1;
-    Z80Byte	IFF2;
-    Z80Byte	IM;
-    Z80Byte	I;
-    Z80Byte	R;
-} Z80State;
-
-
 /* Flags in the F register
 */
 typedef enum
@@ -179,21 +190,6 @@ Z80	*Z80Init(Z80ReadMemory read_memory,
 void	Z80Reset(Z80 *cpu);
 
 
-/* Sets the PC
-*/
-void	Z80SetPC(Z80 *cpu, Z80Word PC);
-
-
-/* Gets the PC
-*/
-Z80Word	Z80GetPC(Z80 *cpu);
-
-
-/* Sets the cycle count to the specified count
-*/
-void	Z80ResetCycles(Z80 *cpu, Z80Val cycles);
-
-
 /* 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).
@@ -233,11 +229,10 @@ int	Z80SingleStep(Z80 *cpu);
 void	Z80Exec(Z80 *cpu);
 
 
-/* Interrogate the state of the Z80
+/* Manipulate the cylce count of the Z80
 */
 Z80Val	Z80Cycles(Z80 *cpu);
-void	Z80GetState(Z80 *cpu, Z80State *state);
-void	Z80SetState(Z80 *cpu, const Z80State *state);
+void	Z80ResetCycles(Z80 *cpu, Z80Val cycles);
 
 
 /* Set address to label mappings for the disassembler
diff --git a/z80_decode.c b/z80_decode.c
index c134b7b..a8f66ca 100644
--- a/z80_decode.c
+++ b/z80_decode.c
@@ -40,8 +40,11 @@ static Z80Byte		Stable[512];
 static Z80Byte		Ztable[512];
 
 
-static int HI;
-static int LO;
+int Z80_HI_WORD;
+int Z80_LO_WORD;
+
+#define HI Z80_HI_WORD
+#define LO Z80_LO_WORD
 
 /* ---------------------------------------- MISC FUNCTIONS
 */
@@ -127,8 +130,8 @@ static Z80Word FPEEKW(Z80 *cpu, Z80Word addr)
 
 static void FPOKEW(Z80 *cpu, Z80Word addr, Z80Word val)
 {
-    cpu->mwrite(cpu,addr,val);
-    cpu->mwrite(cpu,addr+1,val>>8);
+    PRIV->mwrite(cpu,addr,val);
+    PRIV->mwrite(cpu,addr+1,val>>8);
 }
 #endif
 
@@ -1020,9 +1023,9 @@ static void DecodeED(Z80 *cpu, Z80Byte opcode)
 	case 0x40:	/* IN B,(C) */
 	    TSTATE(12);
 
-	    if (cpu->pread)
+	    if (PRIV->pread)
 	    {
-		cpu->BC.b[HI]=cpu->pread(cpu,cpu->BC.w);
+		cpu->BC.b[HI]=PRIV->pread(cpu,cpu->BC.w);
 	    }
 	    else
 	    {
@@ -1035,7 +1038,7 @@ static void DecodeED(Z80 *cpu, Z80Byte opcode)
 
 	case 0x41:	/* OUT (C),B */
 	    TSTATE(12);
-	    if (cpu->pwrite) cpu->pwrite(cpu,cpu->BC.w,cpu->BC.b[HI]);
+	    if (PRIV->pwrite) PRIV->pwrite(cpu,cpu->BC.w,cpu->BC.b[HI]);
 	    break;
 
 	case 0x42:	/* SBC HL,BC */
@@ -1079,9 +1082,9 @@ static void DecodeED(Z80 *cpu, Z80Byte opcode)
 	case 0x48:	/* IN C,(C) */
 	    TSTATE(12);
 
-	    if (cpu->pread)
+	    if (PRIV->pread)
 	    {
-		cpu->BC.b[LO]=cpu->pread(cpu,cpu->BC.w);
+		cpu->BC.b[LO]=PRIV->pread(cpu,cpu->BC.w);
 	    }
 	    else
 	    {
@@ -1094,7 +1097,7 @@ static void DecodeED(Z80 *cpu, Z80Byte opcode)
 
 	case 0x49:	/* OUT (C),C */
 	    TSTATE(12);
-	    if (cpu->pwrite) cpu->pwrite(cpu,cpu->BC.w,cpu->BC.b[LO]);
+	    if (PRIV->pwrite) PRIV->pwrite(cpu,cpu->BC.w,cpu->BC.b[LO]);
 	    break;
 
 	case 0x4a:	/* ADC HL,BC */
@@ -1139,9 +1142,9 @@ static void DecodeED(Z80 *cpu, Z80Byte opcode)
 	case 0x50:	/* IN D,(C) */
 	    TSTATE(12);
 
-	    if (cpu->pread)
+	    if (PRIV->pread)
 	    {
-		cpu->DE.b[HI]=cpu->pread(cpu,cpu->BC.w);
+		cpu->DE.b[HI]=PRIV->pread(cpu,cpu->BC.w);
 	    }
 	    else
 	    {
@@ -1154,7 +1157,7 @@ static void DecodeED(Z80 *cpu, Z80Byte opcode)
 
 	case 0x51:	/* OUT (C),D */
 	    TSTATE(12);
-	    if (cpu->pwrite) cpu->pwrite(cpu,cpu->BC.w,cpu->DE.b[HI]);
+	    if (PRIV->pwrite) PRIV->pwrite(cpu,cpu->BC.w,cpu->DE.b[HI]);
 	    break;
 
 	case 0x52:	/* SBC HL,DE */
@@ -1198,9 +1201,9 @@ static void DecodeED(Z80 *cpu, Z80Byte opcode)
 	case 0x58:	/* IN E,(C) */
 	    TSTATE(12);
 
-	    if (cpu->pread)
+	    if (PRIV->pread)
 	    {
-		cpu->DE.b[LO]=cpu->pread(cpu,cpu->BC.w);
+		cpu->DE.b[LO]=PRIV->pread(cpu,cpu->BC.w);
 	    }
 	    else
 	    {
@@ -1213,7 +1216,7 @@ static void DecodeED(Z80 *cpu, Z80Byte opcode)
 
 	case 0x59:	/* OUT (C),E */
 	    TSTATE(12);
-	    if (cpu->pwrite) cpu->pwrite(cpu,cpu->BC.w,cpu->DE.b[LO]);
+	    if (PRIV->pwrite) PRIV->pwrite(cpu,cpu->BC.w,cpu->DE.b[LO]);
 	    break;
 
 	case 0x5a:	/* ADC HL,DE */
@@ -1257,9 +1260,9 @@ static void DecodeED(Z80 *cpu, Z80Byte opcode)
 	case 0x60:	/* IN H,(C) */
 	    TSTATE(12);
 
-	    if (cpu->pread)
+	    if (PRIV->pread)
 	    {
-		cpu->HL.b[HI]=cpu->pread(cpu,cpu->BC.w);
+		cpu->HL.b[HI]=PRIV->pread(cpu,cpu->BC.w);
 	    }
 	    else
 	    {
@@ -1272,7 +1275,7 @@ static void DecodeED(Z80 *cpu, Z80Byte opcode)
 
 	case 0x61:	/* OUT (C),H */
 	    TSTATE(12);
-	    if (cpu->pwrite) cpu->pwrite(cpu,cpu->BC.w,cpu->HL.b[HI]);
+	    if (PRIV->pwrite) PRIV->pwrite(cpu,cpu->BC.w,cpu->HL.b[HI]);
 	    break;
 
 	case 0x62:	/* SBC HL,HL */
@@ -1327,9 +1330,9 @@ static void DecodeED(Z80 *cpu, Z80Byte opcode)
 	case 0x68:	/* IN L,(C) */
 	    TSTATE(12);
 
-	    if (cpu->pread)
+	    if (PRIV->pread)
 	    {
-		cpu->HL.b[LO]=cpu->pread(cpu,cpu->BC.w);
+		cpu->HL.b[LO]=PRIV->pread(cpu,cpu->BC.w);
 	    }
 	    else
 	    {
@@ -1342,7 +1345,7 @@ static void DecodeED(Z80 *cpu, Z80Byte opcode)
 
 	case 0x69:	/* OUT (C),L */
 	    TSTATE(12);
-	    if (cpu->pwrite) cpu->pwrite(cpu,cpu->BC.w,cpu->HL.b[LO]);
+	    if (PRIV->pwrite) PRIV->pwrite(cpu,cpu->BC.w,cpu->HL.b[LO]);
 	    break;
 
 	case 0x6a:	/* ADC HL,HL */
@@ -1400,9 +1403,9 @@ static void DecodeED(Z80 *cpu, Z80Byte opcode)
 
 	    TSTATE(12);
 
-	    if (cpu->pread)
+	    if (PRIV->pread)
 	    {
-		b=cpu->pread(cpu,cpu->BC.w);
+		b=PRIV->pread(cpu,cpu->BC.w);
 	    }
 	    else
 	    {
@@ -1416,7 +1419,7 @@ static void DecodeED(Z80 *cpu, Z80Byte opcode)
 
 	case 0x71:	/* OUT (C) */
 	    TSTATE(12);
-	    if (cpu->pwrite) cpu->pwrite(cpu,cpu->BC.w,0);
+	    if (PRIV->pwrite) PRIV->pwrite(cpu,cpu->BC.w,0);
 	    break;
 
 	case 0x72:	/* SBC HL,SP */
@@ -1460,9 +1463,9 @@ static void DecodeED(Z80 *cpu, Z80Byte opcode)
 	case 0x78:	/* IN A,(C) */
 	    TSTATE(12);
 
-	    if (cpu->pread)
+	    if (PRIV->pread)
 	    {
-		cpu->AF.b[HI]=cpu->pread(cpu,cpu->BC.w);
+		cpu->AF.b[HI]=PRIV->pread(cpu,cpu->BC.w);
 	    }
 	    else
 	    {
@@ -1475,7 +1478,7 @@ static void DecodeED(Z80 *cpu, Z80Byte opcode)
 
 	case 0x79:	/* OUT (C),A */
 	    TSTATE(12);
-	    if (cpu->pwrite) cpu->pwrite(cpu,cpu->BC.w,cpu->AF.b[HI]);
+	    if (PRIV->pwrite) PRIV->pwrite(cpu,cpu->BC.w,cpu->AF.b[HI]);
 	    break;
 
 	case 0x7a:	/* ADC HL,SP */
@@ -1697,7 +1700,7 @@ static void ShiftedDecodeCB(Z80 *cpu, Z80Byte opcode, Z80Relative offset)
 
     /* See if we've come here from a IX/IY shift.
     */
-    switch (cpu->shift)
+    switch (PRIV->shift)
     {
     	case 0xdd:
 	    addr=cpu->IX.w+offset;
@@ -1762,7 +1765,7 @@ void Z80_Decode(Z80 *cpu, Z80Byte opcode)
 
     /* See if we've come here from a IX/IY shift
     */
-    switch (cpu->shift)
+    switch (PRIV->shift)
     {
     	case 0xdd:
 	    HL=&(cpu->IX.w);
@@ -2168,10 +2171,10 @@ void Z80_Decode(Z80 *cpu, Z80Byte opcode)
 	    TSTATE(4);
 	    cpu->PC--;
 
-	    if (!cpu->halt)
+	    if (!PRIV->halt)
 		CALLBACK(eZ80_Halt,1);
 
-	    cpu->halt=TRUE;
+	    PRIV->halt=TRUE;
 	    break;
 
 	case 0x77:	/* LD (HL),A */
@@ -2244,7 +2247,7 @@ void Z80_Decode(Z80 *cpu, Z80Byte opcode)
 
 	    /* Check for previous IX/IY shift.
 	    */
-	    if (cpu->shift!=0)
+	    if (PRIV->shift!=0)
 	    {
 		Z80Relative cb_offset;
 
@@ -2289,13 +2292,13 @@ void Z80_Decode(Z80 *cpu, Z80Byte opcode)
 
 	case 0xd3:	/* OUT (n),A */
 	    TSTATE(11);
-	    if (cpu->pwrite)
+	    if (PRIV->pwrite)
 	    {
 		Z80Word port;
 
 		port=FETCH_BYTE;
 		port|=(Z80Word)cpu->AF.b[HI]<<8;
-	    	cpu->pwrite(cpu,port,cpu->AF.b[HI]);
+	    	PRIV->pwrite(cpu,port,cpu->AF.b[HI]);
 	    }
 	    else
 	    	cpu->PC++;
@@ -2336,13 +2339,13 @@ void Z80_Decode(Z80 *cpu, Z80Byte opcode)
 
 	case 0xdb:	/* IN A,(n) */
 	    TSTATE(11);
-	    if (cpu->pread)
+	    if (PRIV->pread)
 	    {
 		Z80Word port;
 
 		port=FETCH_BYTE;
 		port|=(Z80Word)cpu->AF.b[HI]<<8;
-		cpu->AF.b[HI]=cpu->pread(cpu,port);
+		cpu->AF.b[HI]=PRIV->pread(cpu,port);
 	    }
 	    else
 	    	cpu->PC++;
@@ -2356,7 +2359,7 @@ void Z80_Decode(Z80 *cpu, Z80Byte opcode)
 	    TSTATE(4);
 	    INC_R;
 
-	    cpu->shift=opcode;
+	    PRIV->shift=opcode;
 	    Z80_Decode(cpu,FETCH_BYTE);
 	    break;
 
@@ -2510,7 +2513,7 @@ void Z80_Decode(Z80 *cpu, Z80Byte opcode)
 	    TSTATE(4);
 	    INC_R;
 
-	    cpu->shift=opcode;
+	    PRIV->shift=opcode;
 	    Z80_Decode(cpu,FETCH_BYTE);
 	    break;
 
diff --git a/z80_dis.c b/z80_dis.c
index 6204f0d..8a8ade8 100644
--- a/z80_dis.c
+++ b/z80_dis.c
@@ -67,7 +67,7 @@ Z80Byte Z80_Dis_FetchByte(Z80 *cpu, Z80Word *pc)
 #ifdef ENABLE_ARRAY_MEMORY
     return Z80_MEMORY[(*pc)++];
 #else
-    return cpu->disread(cpu,(*pc)++);
+    return cpu->priv->disread(cpu,(*pc)++);
 #endif
 }
 
@@ -1463,7 +1463,7 @@ static void DIS_DJNZ (Z80 *z80, Z80Byte op, Z80Word *pc)
 #ifdef ENABLE_ARRAY_MEMORY
     new=*pc+(Z80Relative)Z80_MEMORY[*pc]+1;
 #else
-    new=*pc+(Z80Relative)z80->disread(z80,*pc)+1;
+    new=*pc+(Z80Relative)z80->priv->disread(z80,*pc)+1;
 #endif
     (*pc)++;
     Z80_Dis_Set("djnz",Z80_Dis_Printf("$%.4x",new));
@@ -1482,7 +1482,7 @@ static void DIS_JR (Z80 *z80, Z80Byte op, Z80Word *pc)
 #ifdef ENABLE_ARRAY_MEMORY
     new=*pc+(Z80Relative)Z80_MEMORY[*pc]+1;
 #else
-    new=*pc+(Z80Relative)z80->disread(z80,*pc)+1;
+    new=*pc+(Z80Relative)z80->priv->disread(z80,*pc)+1;
 #endif
     (*pc)++;
 
@@ -1507,7 +1507,7 @@ static void DIS_JR_CO (Z80 *z80, Z80Byte op, Z80Word *pc)
 #ifdef ENABLE_ARRAY_MEMORY
     new=*pc+(Z80Relative)Z80_MEMORY[*pc]+1;
 #else
-    new=*pc+(Z80Relative)z80->disread(z80,*pc)+1;
+    new=*pc+(Z80Relative)z80->priv->disread(z80,*pc)+1;
 #endif
     (*pc)++;
 
diff --git a/z80_private.h b/z80_private.h
index d031497..be45e56 100644
--- a/z80_private.h
+++ b/z80_private.h
@@ -45,40 +45,10 @@
 /* ---------------------------------------- TYPES
 */
 
-typedef signed short	sword;
-
-typedef union
-{
-    Z80Word		w;
-    Z80Byte		b[2];
-} Z80Reg;
-
-struct Z80
+struct Z80Private
 {
     Z80Val		cycle;
 
-    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;
     int			halt;
 
     Z80Byte		shift;
@@ -102,6 +72,8 @@ struct Z80
     int			last_cb;
 };
 
+#define PRIV		cpu->priv
+
 
 /* ---------------------------------------- ARRAY MEMORY
 */
@@ -126,9 +98,9 @@ extern Z80Byte	Z80_MEMORY[];
 			int f;					\
 								\
 			for(f=0;f<MAX_PER_CALLBACK;f++)		\
-			    if (cpu->callback[r][f])		\
-				cpu->last_cb &=			\
-				    cpu->callback[r][f](cpu,d);	\
+			    if (PRIV->callback[r][f])		\
+				PRIV->last_cb &=		\
+				    PRIV->callback[r][f](cpu,d);\
 			} while(0)
 
 /* Flag register
@@ -183,13 +155,13 @@ static inline Z80Word PEEKW(Z80Word addr)
 
 #else
 
-#define PEEK(addr)		(cpu->mread(cpu,addr))
+#define PEEK(addr)		(PRIV->mread(cpu,addr))
 #define PEEKW(addr)		FPEEKW(cpu,addr)
 
-#define POKE(addr,val)		cpu->mwrite(cpu,addr,val)
+#define POKE(addr,val)		PRIV->mwrite(cpu,addr,val)
 #define POKEW(addr,val)		FPOKEW(cpu,addr,val)
 
-#define FETCH_BYTE		(cpu->mread(cpu,cpu->PC++))
+#define FETCH_BYTE		(PRIV->mread(cpu,cpu->PC++))
 #define FETCH_WORD		(cpu->PC+=2,FPEEKW(cpu,cpu->PC-2))
 
 #endif
@@ -204,10 +176,10 @@ static inline Z80Word PEEKW(Z80Word addr)
 
 #define CARRY			IS_C
 
-#define IS_IX_IY		(cpu->shift==0xdd || cpu->shift==0xfd)
+#define IS_IX_IY		(PRIV->shift==0xdd || PRIV->shift==0xfd)
 #define OFFSET(off)		off=(IS_IX_IY ? (Z80Relative)FETCH_BYTE:0)
 
-#define TSTATE(n)		cpu->cycle+=n
+#define TSTATE(n)		PRIV->cycle+=n
 
 #define ADD_R(v)		cpu->R=((cpu->R&0x80)|((cpu->R+(v))&0x7f))
 #define INC_R			ADD_R(1)
@@ -228,8 +200,8 @@ static inline Z80Word PEEKW(Z80Word addr)
 				{					\
 				    Z80Word pushv=REG;			\
 				    cpu->SP-=2;				\
-				    cpu->mwrite(cpu,cpu->SP,pushv);	\
-				    cpu->mwrite(cpu,cpu->SP+1,pushv>>8);\
+				    PRIV->mwrite(cpu,cpu->SP,pushv);	\
+				    PRIV->mwrite(cpu,cpu->SP+1,pushv>>8);\
 				} while(0)
 #endif
 
@@ -257,11 +229,11 @@ static inline Z80Word PEEKW(Z80Word addr)
 
 #define OUT(P,V)		do				\
 				{				\
-				    if (cpu->pwrite)		\
-				    	cpu->pwrite(cpu,P,V);	\
+				    if (PRIV->pwrite)		\
+				    	PRIV->pwrite(cpu,P,V);	\
 				} while(0)
 
-#define IN(P)			(cpu->pread?cpu->pread(cpu,P):0)
+#define IN(P)			(PRIV->pread?PRIV->pread(cpu,P):0)