added led decay simulation as usual

src/mess/drivers/splitsec.c

@@ -25,26 +25,94 @@ public:
 	splitsec_state(const machine_config &mconfig, device_type type, const char *tag)
 		: driver_device(mconfig, type, tag),
 		m_maincpu(*this, "maincpu"),
-//		m_button_matrix(*this, "IN"),
+		m_button_matrix(*this, "IN"),
 		m_speaker(*this, "speaker")
 	{ }
 
 	required_device<cpu_device> m_maincpu;
-//	required_ioport_array<4> m_button_matrix;
+	required_ioport_array<2> m_button_matrix;
 	required_device<speaker_sound_device> m_speaker;
 
 	UINT16 m_r;
 	UINT16 m_o;
 
+	UINT16 m_leds_state[0x10];
+	UINT16 m_leds_cache[0x10];
+	UINT8 m_leds_decay[0x100];
+
 	DECLARE_READ8_MEMBER(read_k);
 	DECLARE_WRITE16_MEMBER(write_o);
 	DECLARE_WRITE16_MEMBER(write_r);
 
+	TIMER_DEVICE_CALLBACK_MEMBER(leds_decay_tick);
+	void leds_update();
+
 	virtual void machine_start();
 };
 
 
 
+/***************************************************************************
+
+  LEDs
+
+***************************************************************************/
+
+// The device strobes the outputs very fast, it is unnoticeable to the user.
+// To prevent flickering here, we need to simulate a decay.
+
+// decay time, in steps of 10ms
+#define LEDS_DECAY_TIME 4
+
+void splitsec_state::leds_update()
+{
+	UINT16 active_state[0x10];
+
+	for (int i = 0; i < 0x10; i++)
+	{
+		// update current state
+		if (m_r >> i & 1)
+			m_leds_state[i] = m_o;
+
+		active_state[i] = 0;
+
+		for (int j = 0; j < 0x10; j++)
+		{
+			int di = j << 4 | i;
+
+			// turn on powered leds
+			if (m_leds_state[i] >> j & 1)
+				m_leds_decay[di] = LEDS_DECAY_TIME;
+
+			// determine active state
+			int ds = (m_leds_decay[di] != 0) ? 1 : 0;
+			active_state[i] |= (ds << j);
+		}
+	}
+
+	// on difference, send to output
+	for (int i = 0; i < 0x10; i++)
+		if (m_leds_cache[i] != active_state[i])
+		{
+			for (int j = 0; j < 8; j++)
+				output_set_lamp_value(i*10 + j, active_state[i] >> j & 1);
+		}
+
+	memcpy(m_leds_cache, active_state, sizeof(m_leds_cache));
+}
+
+TIMER_DEVICE_CALLBACK_MEMBER(splitsec_state::leds_decay_tick)
+{
+	// slowly turn off unpowered leds
+	for (int i = 0; i < 0x100; i++)
+		if (!(m_leds_state[i & 0xf] >> (i>>4) & 1) && m_leds_decay[i])
+			m_leds_decay[i]--;
+
+	leds_update();
+}
+
+
+
 /***************************************************************************
 
   I/O
@@ -53,17 +121,33 @@ public:
 
 READ8_MEMBER(splitsec_state::read_k)
 {
-	return 0;
+	UINT8 k = 0;
+
+	// read selected button rows
+	for (int i = 0; i < 2; i++)
+		if (m_r >> (i+9) & 1)
+			k |= m_button_matrix[i]->read();
+
+	return k;
 }
 
 WRITE16_MEMBER(splitsec_state::write_r)
 {
+	// R8: speaker out
+	m_speaker->level_w(data >> 8 & 1);
+	
+	// R9,R10: input mux
+	// R0-R7: led columns
 	m_r = data;
+	leds_update();
 }
 
 WRITE16_MEMBER(splitsec_state::write_o)
 {
+	// O0-O6: led rows
+	// O7: N/C
 	m_o = data;
+	leds_update();
 }
 
 
@@ -75,6 +159,17 @@ WRITE16_MEMBER(splitsec_state::write_o)
 ***************************************************************************/
 
 static INPUT_PORTS_START( splitsec )
+	PORT_START("IN.0") // R9
+	PORT_BIT( 0x01, IP_ACTIVE_HIGH, IPT_JOYSTICK_RIGHT )
+	PORT_BIT( 0x02, IP_ACTIVE_HIGH, IPT_JOYSTICK_UP )
+	PORT_BIT( 0x04, IP_ACTIVE_HIGH, IPT_JOYSTICK_LEFT )
+	PORT_BIT( 0x08, IP_ACTIVE_HIGH, IPT_UNUSED )
+
+	PORT_START("IN.1") // R10
+	PORT_BIT( 0x01, IP_ACTIVE_HIGH, IPT_JOYSTICK_DOWN )
+	PORT_BIT( 0x02, IP_ACTIVE_HIGH, IPT_BUTTON1 ) PORT_NAME("Select")
+	PORT_BIT( 0x04, IP_ACTIVE_HIGH, IPT_BUTTON2 ) PORT_NAME("Start")
+	PORT_BIT( 0x08, IP_ACTIVE_HIGH, IPT_UNUSED )
 INPUT_PORTS_END
 
 
@@ -87,9 +182,19 @@ INPUT_PORTS_END
 
 void splitsec_state::machine_start()
 {
+	// zerofill
+	memset(m_leds_state, 0, sizeof(m_leds_state));
+	memset(m_leds_cache, 0, sizeof(m_leds_cache));
+	memset(m_leds_decay, 0, sizeof(m_leds_decay));
+
 	m_r = 0;
 	m_o = 0;
 
+	// register for savestates
+	save_item(NAME(m_leds_state));
+	save_item(NAME(m_leds_cache));
+	save_item(NAME(m_leds_decay));
+
 	save_item(NAME(m_r));
 	save_item(NAME(m_o));
 }
@@ -103,6 +208,8 @@ static MACHINE_CONFIG_START( splitsec, splitsec_state )
 	MCFG_TMS1XXX_WRITE_O_CB(WRITE16(splitsec_state, write_o))
 	MCFG_TMS1XXX_WRITE_R_CB(WRITE16(splitsec_state, write_r))
 
+	MCFG_TIMER_DRIVER_ADD_PERIODIC("leds_decay", splitsec_state, leds_decay_tick, attotime::from_msec(10))
+
 	MCFG_DEFAULT_LAYOUT(layout_splitsec)
 
 	/* no video! */