Sped up Z80 emulation

4 files changed, 36 insertions, 23 deletions

diff --git a/include/spec.h b/include/spec.h
index 85fb5e7..8171a4f 100644
--- a/include/spec.h
+++ b/include/spec.h
@@ -67,13 +67,9 @@ void	SPECReconfigure(void);
 
 /* Interfaces for the Z80
 */
-Z80Byte	SPECReadMem(Z80 *z80, Z80Word addr);
-void	SPECWriteMem(Z80 *z80, Z80Word addr, Z80Byte val);
 Z80Byte	SPECReadPort(Z80 *z80, Z80Word port);
 void	SPECWritePort(Z80 *z80, Z80Word port, Z80Byte val);
 
-#define	SPECReadDisassem SPECReadMem
-
 /* Interface for snap
 */
 void    SPECWriteMemSNAP(Z80Word addr, Z80Byte val);
diff --git a/include/z80.h b/include/z80.h
index ab095d8..c9bd107 100644
--- a/include/z80.h
+++ b/include/z80.h
@@ -56,20 +56,30 @@ 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.
+/* A Z80 16-bit register made up of 2 8-bit registers.
 */
+#ifdef Z80_LITTLE_ENDIAN
+typedef struct
+{
+    Z80Byte             lo;
+    Z80Byte             hi;
+} Z80RegPair;
+#endif
+
+#ifdef Z80_BIG_ENDIAN
+typedef struct
+{
+    Z80Byte             hi;
+    Z80Byte             lo;
+} Z80RegPair;
+#endif
+
 typedef union
 {
     Z80Word		w;
-    Z80Byte		b[2];
+    Z80RegPair          b;
 } Z80Reg;
 
-extern int Z80_HI_WORD;
-extern int Z80_LO_WORD;
-
-
 /* The processor
 */
 struct Z80Private;
diff --git a/include/z80_config.h b/include/z80_config.h
index 8d9ee79..2a56cb1 100644
--- a/include/z80_config.h
+++ b/include/z80_config.h
@@ -36,6 +36,11 @@
 */
 #define ENABLE_DISASSEM
 
+/* Pick one of these as appropriate for your real CPU
+#define Z80_BIG_ENDIAN
+*/
+#define Z80_LITTLE_ENDIAN
+
 
 /* Define this to enable the array-based memory model.  In this mode
    an externally visible Z80Byte array called Z80_MEMORY must be
@@ -44,11 +49,11 @@
 
    In this mode the signature of Z80Init changes so that the memory functions
    are not passed.  ALL processor instances share the same memory.
-#define ENABLE_ARRAY_MEMORY
 */
+#define ENABLE_ARRAY_MEMORY
 
 #ifdef ENABLE_ARRAY_MEMORY
-#define RAMBOT 0x0000
+#define RAMBOT 0x4000
 #define RAMTOP 0xffff
 #endif
 
diff --git a/include/z80_private.h b/include/z80_private.h
index e0b3381..a7022d8 100644
--- a/include/z80_private.h
+++ b/include/z80_private.h
@@ -121,13 +121,15 @@ extern Z80Byte	Z80_MEMORY[];
 #define SET(v,b)		(v)|=b
 #define CLR(v,b)		(v)&=~(b)
 
-#define SETFLAG(f)		SET(cpu->AF.b[LO],f)
-#define CLRFLAG(f)		CLR(cpu->AF.b[LO],f)
+#define SETFLAG(f)		SET(cpu->AF.b.lo,f)
+#define CLRFLAG(f)		CLR(cpu->AF.b.lo,f)
 
 #ifdef ENABLE_ARRAY_MEMORY
 
 #define PEEK(addr)		Z80_MEMORY[addr]
 
+/* This can't be a macro as the macro is used as PEEKW(FETCH_WORD)
+*/
 static inline Z80Word PEEKW(Z80Word addr)
 {
     return (PEEK(addr) | (Z80Word)PEEK(addr+1)<<8);
@@ -168,12 +170,12 @@ static inline Z80Word PEEKW(Z80Word addr)
 #endif
 
 
-#define IS_C			(cpu->AF.b[LO]&C_Z80)
-#define IS_N			(cpu->AF.b[LO]&N_Z80)
-#define IS_P			(cpu->AF.b[LO]&P_Z80)
-#define IS_H			(cpu->AF.b[LO]&H_Z80)
-#define IS_Z			(cpu->AF.b[LO]&Z_Z80)
-#define IS_S			(cpu->AF.b[LO]&S_Z80)
+#define IS_C			(cpu->AF.b.lo&C_Z80)
+#define IS_N			(cpu->AF.b.lo&N_Z80)
+#define IS_P			(cpu->AF.b.lo&P_Z80)
+#define IS_H			(cpu->AF.b.lo&H_Z80)
+#define IS_Z			(cpu->AF.b.lo&Z_Z80)
+#define IS_S			(cpu->AF.b.lo&S_Z80)
 
 #define CARRY			IS_C
 
@@ -219,7 +221,7 @@ static inline Z80Word PEEKW(Z80Word addr)
 				    cpu->SP+=2;				\
 				} while(0)
 
-#define SETHIDDEN(res)		cpu->AF.b[LO]=(cpu->AF.b[LO]&~(B3_Z80|B5_Z80))|\
+#define SETHIDDEN(res)		cpu->AF.b.lo=(cpu->AF.b.lo&~(B3_Z80|B5_Z80))|\
 					((res)&(B3_Z80|B5_Z80))
 
 #define CALL			do				\