rm/rmnimbus.cpp: Allow choice of HLE mouse processing (#11890)

src/mame/rm/rmnimbus.cpp

@@ -68,6 +68,11 @@ void rmnimbus_state::nimbus_io(address_map &map)
 
 
 static INPUT_PORTS_START( nimbus )
+	PORT_START("config")
+	PORT_CONFNAME( 0x01, 0x00, "Mouse emulation mode" )
+	PORT_CONFSETTING( 0x00, "Real" )
+	PORT_CONFSETTING( 0x01, "HLE" )
+
 	PORT_START(JOYSTICK0_TAG)
 	PORT_BIT( 0x01, IP_ACTIVE_HIGH, IPT_JOYSTICK_LEFT )  PORT_PLAYER(1) PORT_8WAY
 	PORT_BIT( 0x02, IP_ACTIVE_HIGH, IPT_JOYSTICK_RIGHT ) PORT_PLAYER(1) PORT_8WAY

src/mame/rm/rmnimbus.h

@@ -77,6 +77,7 @@ public:
 		m_fdc(*this, FDC_TAG),
 		m_z80sio(*this, Z80SIO_TAG),
 		m_screen(*this, "screen"),
+		m_io_config(*this, "config"),
 		m_io_joysticks(*this, JOYSTICK_TAG_BASE "%u", 0),
 		m_io_mouse_button(*this, MOUSE_BUTTON_TAG),
 		m_io_mousex(*this, MOUSEX_TAG),
@@ -104,6 +105,7 @@ private:
 	required_device<wd2793_device> m_fdc;
 	required_device<z80sio_device> m_z80sio;
 	required_device<screen_device> m_screen;
+	required_ioport m_io_config;
 	required_ioport_array<2> m_io_joysticks;
 	required_ioport m_io_mouse_button;
 	required_ioport m_io_mousex;
@@ -227,6 +229,13 @@ private:
 	/* Mouse */
 	struct
 	{
+		uint16_t xpos_loc = 0;
+		uint16_t ypos_loc = 0;
+		uint16_t xmin_loc = 0;
+		uint16_t ymin_loc = 0;
+		uint16_t xmax_loc = 0;
+		uint16_t ymax_loc = 0;
+
 		uint8_t m_mouse_x = 0;
 		uint8_t m_mouse_y = 0;
 
@@ -263,6 +272,8 @@ private:
 	offs_t dasm_override(std::ostream &stream, offs_t pc, const util::disasm_interface::data_buffer &opcodes, const util::disasm_interface::data_buffer &params);
 
 	TIMER_CALLBACK_MEMBER(do_mouse);
+	void do_mouse_real(int8_t xdiff, int8_t ydiff);
+	void do_mouse_hle(int8_t xdiff, int8_t ydiff);
 };
 
 #endif // MAME_RM_RMNIMBUS_H

src/mame/rm/rmnimbus_m.cpp

@@ -980,6 +980,29 @@ TIMER_CALLBACK_MEMBER(rmnimbus_state::do_mouse)
 	int8_t  xdiff;          // Difference from previous X and Y
 	int8_t  ydiff;
 
+	// Read mose positions and calculate difference from previous value
+	mouse_x = m_io_mousex->read();
+	mouse_y = m_io_mousey->read();
+
+	xdiff = m_nimbus_mouse.m_mouse_x - mouse_x;
+	ydiff = m_nimbus_mouse.m_mouse_y - mouse_y;
+
+	if (m_io_config->read() & 0x01)
+	{
+		do_mouse_hle(xdiff, ydiff);
+	}
+	else
+	{
+		do_mouse_real(xdiff, ydiff);
+	}
+
+	// Update current mouse position
+	m_nimbus_mouse.m_mouse_x = mouse_x;
+	m_nimbus_mouse.m_mouse_y = mouse_y;
+}
+
+void rmnimbus_state::do_mouse_real(int8_t xdiff, int8_t ydiff)
+{
 	uint8_t intstate_x;     // Used to calculate if we should trigger interrupt
 	uint8_t intstate_y;
 	int     xint;           // X and Y interrupts to trigger
@@ -990,13 +1013,6 @@ TIMER_CALLBACK_MEMBER(rmnimbus_state::do_mouse)
 	uint8_t   mya;
 	uint8_t   myb;
 
-	// Read mose positions and calculate difference from previous value
-	mouse_x = m_io_mousex->read();
-	mouse_y = m_io_mousey->read();
-
-	xdiff = m_nimbus_mouse.m_mouse_x - mouse_x;
-	ydiff = m_nimbus_mouse.m_mouse_y - mouse_y;
-
 	// convert movement into emulated movement of quadrature encoder in mouse.
 	if (xdiff < 0)
 		m_nimbus_mouse.m_mouse_pcx++;
@@ -1049,17 +1065,78 @@ TIMER_CALLBACK_MEMBER(rmnimbus_state::do_mouse)
 		m_nimbus_mouse.m_reg0a4 |= ( myb & 0x01) << 0; // YB
 	}
 
-	// Update current mouse position
-	m_nimbus_mouse.m_mouse_x = mouse_x;
-	m_nimbus_mouse.m_mouse_y = mouse_y;
-
 	// and interrupt state
 	m_nimbus_mouse.m_intstate_x=intstate_x;
 	m_nimbus_mouse.m_intstate_y=intstate_y;
 }
 
+void rmnimbus_state::do_mouse_hle(int8_t xdiff, int8_t ydiff)
+{
+	if (MOUSE_INT_ENABLED(this))
+	{
+		// bypass bios ISR and update mouse cursor position locations directly
+		address_space &space = m_maincpu->space(AS_PROGRAM);
+
+		if (xdiff)
+		{
+			uint16_t x = space.read_word_unaligned(m_nimbus_mouse.xpos_loc);
+			if ((xdiff < 0) && (x != space.read_word_unaligned(m_nimbus_mouse.xmax_loc)))
+			{
+				x++;
+			}
+			else if (x != space.read_word_unaligned(m_nimbus_mouse.xmin_loc))
+			{
+				x--;
+			}
+			space.write_word_unaligned(m_nimbus_mouse.xpos_loc, x);
+		}
+
+		if (ydiff)
+		{
+			uint16_t y = space.read_word_unaligned(m_nimbus_mouse.ypos_loc);
+			if ((ydiff < 0) && (y != space.read_word_unaligned(m_nimbus_mouse.ymin_loc)))
+			{
+				y--;
+			}
+			else if (y != space.read_word_unaligned(m_nimbus_mouse.ymax_loc))
+			{
+				y++;
+			}
+			space.write_word_unaligned(m_nimbus_mouse.ypos_loc, y);
+		}
+	}
+	else
+	{
+		// store status to support polling operation of mouse
+		// (not tested as no software seems to use this method!)
+		if (xdiff || ydiff)
+		{
+			m_nimbus_mouse.m_reg0a4 = 0;
+		}
+		if (xdiff < 0)
+		{
+			m_nimbus_mouse.m_reg0a4 |= CONTROLLER_RIGHT;
+		}
+		else if (xdiff > 0)
+		{
+			m_nimbus_mouse.m_reg0a4 |= CONTROLLER_LEFT;
+		}
+		if (ydiff < 0)
+		{
+			m_nimbus_mouse.m_reg0a4 |= CONTROLLER_DOWN;
+		}
+		else if (ydiff > 0)
+		{
+			m_nimbus_mouse.m_reg0a4 |= CONTROLLER_UP;
+		}
+
+	}
+}
+
 void rmnimbus_state::mouse_js_reset()
 {
+	constexpr uint16_t bios_addresses[] = { 0x18cd, 0x196d, 0x196d, 0x1a6d, 0x1a6d, 0x1a77 };
+
 	m_nimbus_mouse.m_mouse_x=128;
 	m_nimbus_mouse.m_mouse_y=128;
 	m_nimbus_mouse.m_mouse_pcx=0;
@@ -1068,6 +1145,15 @@ void rmnimbus_state::mouse_js_reset()
 	m_nimbus_mouse.m_intstate_y=0;
 	m_nimbus_mouse.m_reg0a4=0xC0;
 
+	// calculate addresses for mouse related variable used by the bios mouse ISR
+	auto bios_base = bios_addresses[system_bios() - 1];
+	m_nimbus_mouse.xpos_loc = bios_base + 8;
+	m_nimbus_mouse.ypos_loc = bios_base + 10;
+	m_nimbus_mouse.xmin_loc = bios_base;
+	m_nimbus_mouse.ymin_loc = bios_base + 4;
+	m_nimbus_mouse.xmax_loc = bios_base + 2;
+	m_nimbus_mouse.ymax_loc = bios_base + 6;
+
 	// Setup timer to poll the mouse
 	m_nimbus_mouse.m_mouse_timer->adjust(attotime::zero, 0, attotime::from_hz(MOUSE_POLL_FREQUENCY));
 
@@ -1078,8 +1164,9 @@ uint8_t rmnimbus_state::nimbus_joystick_r()
 {
 	/* Only the joystick drection data is read from this port
 	   (which corresponds to the the low nibble of the selected joystick port).
-	   The joystick buttons are read from the mouse data port instead. */
+	   The joystick buttons are read from the mouse data port instead.
-	uint8_t result = m_io_joysticks[m_selected_js_idx]->read() & 0x0f;
+	   Unused bits are set to 1. */
+	uint8_t result = m_io_joysticks[m_selected_js_idx]->read() | 0xf0;
 
 	if (result & CONTROLLER_RIGHT)
 	{