sega/segaybd.cpp: Switch Sega Y-Board games back to Musashi (MT08783)…

…. [R. Belmont]

cpu/m68000: added option to use Musashi for M68000 emulation. [R. Belmont]

scripts/src/cpu.lua

@@ -2042,6 +2042,8 @@ if CPUS["M680X0"] then
 		MAME_DIR .. "src/devices/cpu/m68000/m68008-sip8.cpp",
 		MAME_DIR .. "src/devices/cpu/m68000/m68008.h",
 		MAME_DIR .. "src/devices/cpu/m68000/m68008.cpp",
+		MAME_DIR .. "src/devices/cpu/m68000/m68000musashi.h",
+		MAME_DIR .. "src/devices/cpu/m68000/m68000musashi.cpp",
 		MAME_DIR .. "src/devices/cpu/m68000/m68010.h",
 		MAME_DIR .. "src/devices/cpu/m68000/m68010.cpp",
 		MAME_DIR .. "src/devices/cpu/m68000/m68020.h",

src/devices/cpu/m68000/m68000musashi.cpp

@@ -0,0 +1,25 @@
+// license:BSD-3-Clause
+// copyright-holders:Karl Stenerud
+
+#include "emu.h"
+#include "m68000musashi.h"
+#include "m68kdasm.h"
+
+DEFINE_DEVICE_TYPE(M68000MUSASHI,      m68000msh_device,      "m68000msh",       "Motorola MC68000 (Musashi)")
+
+std::unique_ptr<util::disasm_interface> m68000msh_device::create_disassembler()
+{
+	return std::make_unique<m68k_disassembler>(m68k_disassembler::TYPE_68010);
+}
+
+
+m68000msh_device::m68000msh_device(const machine_config &mconfig, const char *tag, device_t *owner, u32 clock)
+	: m68000_musashi_device(mconfig, tag, owner, clock, M68000MUSASHI, 16, 24)
+{
+}
+
+void m68000msh_device::device_start()
+{
+	m68000_musashi_device::device_start();
+	init_cpu_m68000();
+}

src/devices/cpu/m68000/m68000musashi.h

@@ -0,0 +1,27 @@
+// license:BSD-3-Clause
+// copyright-holders:Karl Stenerud
+#ifndef MAME_CPU_M68000_M68000MUSASHI_H
+#define MAME_CPU_M68000_M68000MUSASHI_H
+
+#pragma once
+
+#include "m68kmusashi.h"
+
+class m68000msh_device : public m68000_musashi_device
+{
+public:
+	// construction/destruction
+	m68000msh_device(const machine_config &mconfig, const char *tag, device_t *owner, u32 clock);
+
+	virtual std::unique_ptr<util::disasm_interface> create_disassembler() override;
+
+	virtual u32 execute_min_cycles() const noexcept override { return 4; }
+	virtual u32 execute_max_cycles() const noexcept override { return 158; }
+
+	// device-level overrides
+	virtual void device_start() override;
+};
+
+DECLARE_DEVICE_TYPE(M68000MUSASHI, m68000msh_device)
+
+#endif

src/mame/sega/segaybd.cpp

@@ -1428,13 +1428,13 @@ INPUT_PORTS_END
 void segaybd_state::yboard(machine_config &config)
 {
 	// basic machine hardware
-	M68000(config, m_maincpu, MASTER_CLOCK/4);
+	M68000MUSASHI(config, m_maincpu, MASTER_CLOCK/4);
 	m_maincpu->set_addrmap(AS_PROGRAM, &segaybd_state::main_map);
 
-	M68000(config, m_subx, MASTER_CLOCK/4);
+	M68000MUSASHI(config, m_subx, MASTER_CLOCK/4);
 	m_subx->set_addrmap(AS_PROGRAM, &segaybd_state::subx_map);
 
-	M68000(config, m_suby, MASTER_CLOCK/4);
+	M68000MUSASHI(config, m_suby, MASTER_CLOCK/4);
 	m_suby->set_addrmap(AS_PROGRAM, &segaybd_state::suby_map);
 
 	Z80(config, m_soundcpu, SOUND_CLOCK/8);

src/mame/sega/segaybd.h

@@ -10,7 +10,7 @@
 
 #pragma once
 
-#include "cpu/m68000/m68000.h"
+#include "cpu/m68000/m68000musashi.h"
 #include "cpu/z80/z80.h"
 #include "machine/mb3773.h"
 #include "segaic16.h"
@@ -123,9 +123,9 @@ class segaybd_state : public sega_16bit_common_base
 	void update_irqs();
 
 	// devices
-	required_device<m68000_device> m_maincpu;
-	required_device<m68000_device> m_subx;
-	required_device<m68000_device> m_suby;
+	required_device<m68000msh_device> m_maincpu;
+	required_device<m68000msh_device> m_subx;
+	required_device<m68000msh_device> m_suby;
 	required_device<z80_device> m_soundcpu;
 	optional_device<z80_device> m_linkcpu;
 	required_device<mb3773_device> m_watchdog;