Command 'go <startaddr>' works now

Add debug command to display AVR RAM

1 files changed, 196 insertions, 53 deletions

diff --git a/avr/z80-if.c b/avr/z80-if.c
index 949de17..ab8e293 100644
--- a/avr/z80-if.c
+++ b/avr/z80-if.c
@@ -55,6 +55,7 @@
 
 #include <avr/io.h>
 #include <util/delay.h>
+#include <util/atomic.h>
 #include <stdio.h>
 #include "debug.h"
 #include "z80-if.h"
@@ -137,48 +138,6 @@ struct bits {
 //#define Z80_I_HALT	SBIT(P_HALT, )
 
 
-#if 0
-void z80_busreq(level_t level)
-{
-	Z80_O_BUSREQ = level;
-}
-#endif
-
-void z80_reset(level_t level)
-{
-	Z80_O_RST = level;
-	if (level)
-		Stat |= S_Z180_RUNNING;
-	else
-		Stat &= ~S_Z180_RUNNING;
-}
-
-int z80_stat_reset(void)
-{
-	return Z80_O_RST;
-}
-
-void z80_reset_pulse(void)
-{
-	Z80_O_RST = 0;
-	_delay_us(10);
-	Z80_O_RST = 1;
-	Stat |= S_Z180_RUNNING;
-}
-
-int z80_runstate(void)
-{
-	return (Stat & S_Z180_RUNNING) != 0;
-}
-
-#if 0
-int z80_stat_halt(void)
-{
-	return Z80_I_HALT;
-}
-#endif
-
-
 #define MASK(n)	((1<<(n))-1)
 #define SMASK(w,s) (MASK(w) << (s))
 
@@ -189,7 +148,9 @@ typedef union {
 	uint16_t w[2];
 	uint8_t b[4];
 } addr_t;
- 
+
+
+static zstate_t zstate;
 
 /*--------------------------------------------------------------------------*/
 
@@ -258,32 +219,214 @@ void z80_setup_bus(void)
 	z80_setup_addrbus_tristate();
 	z80_setup_dbus_in();
 
-	Stat &= ~S_Z180_RUNNING;
+	zstate = RESET;
+//	Stat &= ~S_Z180_RUNNING;
 }
 
 /*--------------------------------------------------------------------------*/
+#if 0
+	switch (zstate) {
+	case RESET:
+		break;
+	case RESET_AQRD:
+		break;
+	case RUN:
+		break;
+	case RUN_AQRD:
+		break;
+	}
+#endif
+/*--------------------------------------------------------------------------*/
 
-void z80_request_bus(void)
+#if 0
+void z80_busreq(level_t level)
+{
+	Z80_O_BUSREQ = level;
+}
+
+int z80_stat_reset(void)
+{
+//	return Z80_O_RESET;
+}
+
+int z80_stat_halt(void)
+{
+	return Z80_I_HALT;
+}
+#endif
+
+
+zstate_t z80_runstate(void)
+{
+	return zstate;
+}
+
+void z80_reset(void)
+{
+#if DEBUG
+	zstate_t old = zstate;
+#endif
+	z80_setup_dbus_in();
+	z80_setup_addrbus_tristate();
+	Z80_O_RST = 0;
+	Z80_O_BUSREQ = 1;
+	zstate = RESET;
+
+	debug("z80_reset: state: %02x --> %02x\n", old, zstate);
+}
+
+void z80_reset_pulse(void)
 {
-	Z80_O_BUSREQ = 0;
+#if DEBUG
+	zstate_t old = zstate;
+#endif
+	switch (zstate) {
+	case RESET:
+	case RESET_AQRD:
+		break;
 
-	if (!(Stat & S_Z180_RUNNING))
+	case RUN:
+	case RUN_AQRD:
+		Z80_O_RST = 0;
+		_delay_us(10);
 		Z80_O_RST = 1;
+		break;
+	}
 
-	while(Z80_I_BUSACK == 1);
-	z80_setup_addrbus_active();
+	debug("z80_reset_pulse: state: %02x --> %02x\n", old, zstate);
+}
+
+void z80_request_bus(void)
+{
+#if DEBUG
+	zstate_t old = zstate;
+#endif
+
+	switch (zstate) {
+	case RESET:
+		Z80_O_BUSREQ = 0;
+		Z80_O_RST = 1;
+		while(Z80_I_BUSACK == 1)
+			;
+		z80_setup_addrbus_active();
+		zstate = RESET_AQRD;
+		break;
+
+	case RESET_AQRD:
+		break;
+
+	case RUN:
+		Z80_O_BUSREQ = 0;
+		while(Z80_I_BUSACK == 1);
+		z80_setup_addrbus_active();
+		zstate = RUN_AQRD;
+		break;
+
+	case RUN_AQRD:
+		break;
+	}
+	debug("z80_request_bus: state: %02x --> %02x\n", old, zstate);
 }
 
 void z80_release_bus(void)
 {
+#if DEBUG
+	zstate_t old = zstate;
+#endif
+	switch (zstate) {
+	case RESET:
+		break;
+	case RESET_AQRD:
+		z80_setup_dbus_in();
+		z80_setup_addrbus_tristate();
+		Z80_O_RST = 0;
+		Z80_O_BUSREQ = 1;
+		zstate = RESET;
+		break;
+	case RUN:
+		break;
+	case RUN_AQRD:
+		z80_setup_dbus_in();
+		z80_setup_addrbus_tristate();
+		Z80_O_BUSREQ = 1;
+		zstate = RUN;
+		break;
+	}
+
+	debug("z80_release_bus: state: %02x --> %02x\n", old, zstate);
+}
+
+/*
+ * Do nothing, if we have the bus allready
+ *
+ * return previous state
+ */
+zstate_t z80_request_bus_save(void)
+{
+	zstate_t state;
+	
+	state = z80_runstate();
+	if (!(state & ZST_ACQUIRED))
+		z80_request_bus();
+
+	return state;
+}		
+
+/*
+ * Do nothing, if we had the bus before
+ */
+void z80_release_bus_save(zstate_t prev)
+{
+	if (!(prev & ZST_ACQUIRED))
+		z80_release_bus();
+}		
+
+void z80_run(void)
+{
+#if DEBUG
+	zstate_t old = zstate;
+#endif
+	switch (zstate) {
+	case RESET:
+		Z80_O_RST = 1;
+		zstate = RUN;
+		break;
+
+	case RESET_AQRD:
+		z80_setup_dbus_in();
+		z80_setup_addrbus_tristate();
+		Z80_O_RST = 0;
+		_delay_us(10);
+		Z80_O_RST = 1;
+		z80_setup_addrbus_active();
+		zstate = RUN_AQRD;
+		break;
+
+	case RUN:
+		break;
+	case RUN_AQRD:
+		break;
+	}
+
+	debug("z80_run: state: %02x --> %02x\n", old, zstate);
+}
+
+void z80_busreq_hpulse(void)
+{
 	z80_setup_dbus_in();
 	z80_setup_addrbus_tristate();
 
-	if (!(Stat & S_Z180_RUNNING))
-		Z80_O_RST = 0;
+	ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
+		Z80_O_BUSREQ = 1;
+		Z80_O_BUSREQ = 1;	/* 2 AVR clock cycles */
+		Z80_O_BUSREQ = 0;	/* 2 AVR clock cycles */
+	}
 
-	Z80_O_BUSREQ = 1;
-	//while(Z80_I_BUSACK == 0);
+	if (zstate & ZST_ACQUIRED) {
+		while(Z80_I_BUSACK == 1)
+			;
+		z80_setup_addrbus_active();
+	}
 }
 
 /*--------------------------------------------------------------------------*/