g65816: WDM is a 2-byte opcode per WDC docs, added WDM callback. [R. Belmont]

src/devices/cpu/g65816/g65816.cpp

@@ -17,6 +17,10 @@ All rights reserved.
 /*
 
 Changes:
+    1.02 (2019-02-02):
+        R. Belmont
+        - Corrected WDM to take 2 bytes and added callback
+
     1.01 (2010-04-04):
         Angelo Salese
         - Added boundary checks for MVP and MVN in M mode.
@@ -115,6 +119,7 @@ g65816_device::g65816_device(const machine_config &mconfig, device_type type, co
 	, m_data_config("data", ENDIANNESS_LITTLE, 8, 24, 0, internal)
 	, m_opcode_config("opcodes", ENDIANNESS_LITTLE, 8, 24, 0, internal)
 	, m_vector_config("vectors", ENDIANNESS_LITTLE, 8, 5, 0)
+	, m_wdm_w(*this)
 	, m_cpu_type(cpu_type)
 {
 }
@@ -860,6 +865,8 @@ void g65816_device::device_start()
 	m_program_cache = program_space.cache<0, 0, ENDIANNESS_LITTLE>();
 	m_opcode_cache = (has_space(AS_OPCODES) ? space(AS_OPCODES) : program_space).cache<0, 0, ENDIANNESS_LITTLE>();
 
+	m_wdm_w.resolve_safe();
+
 	save_item(NAME(m_a));
 	save_item(NAME(m_b));
 	save_item(NAME(m_x));

src/devices/cpu/g65816/g65816.h

@@ -56,6 +56,8 @@ public:
 	// construction/destruction
 	g65816_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock);
 
+	auto wdm_handler() { return m_wdm_w.bind(); }
+
 protected:
 	/* Registers - used by g65816_set_reg() and g65816_get_reg() */
 	enum
@@ -96,6 +98,7 @@ protected:
 	address_space_config m_data_config;
 	address_space_config m_opcode_config;
 	address_space_config m_vector_config;
+	devcb_write8 m_wdm_w;     /* WDM callback */
 
 	typedef void (g65816_device::*opcode_func) ();
 	typedef unsigned (g65816_device::*get_reg_func)(int regnum);

src/devices/cpu/g65816/g65816ds.cpp

@@ -101,7 +101,7 @@ const g65816_disassembler::opcode_struct g65816_disassembler::s_opcodes[256] =
 	{op::BIT, M, DX  }, {op::AND, M, DX  }, {op::ROL, M, DX  }, {op::AND, M, DLIY},
 	{op::SEC, I, IMP }, {op::AND, M, AY  }, {op::DEA, I, IMP }, {op::TSC, I, IMP },
 	{op::BIT, M, AX  }, {op::AND, M, AX  }, {op::ROL, M, AX  }, {op::AND, M, ALX },
-	{op::RTI, I, IMP }, {op::EOR, M, DXI }, {op::WDM, I, IMP }, {op::EOR, M, S   },
+	{op::RTI, I, IMP }, {op::EOR, M, DXI }, {op::WDM, I, SIG }, {op::EOR, M, S   },
 	{op::MVP, I, MVP }, {op::EOR, M, D   }, {op::LSR, M, D   }, {op::EOR, M, DLI },
 	{op::PHA, I, IMP }, {op::EOR, M, IMM }, {op::LSR, M, ACC }, {op::PHK, I, IMP },
 	{op::JMP, I, A   }, {op::EOR, M, A   }, {op::LSR, M, A   }, {op::EOR, M, AL  },

src/devices/cpu/g65816/g65816op.h

@@ -1428,7 +1428,8 @@
 #undef OP_WDM
 #define OP_WDM()                                                            \
 			CLK(CLK_OP + CLK_IMPLIED);                                      \
-			REGISTER_PC++
+			SRC = OPER_8_IMM();                                             \
+			m_wdm_w(SRC);
 
 /* G65816  Exchange accum high and low bytes */
 #undef OP_XBA