snes_snd.cpp: merge timer counters into one single function [Angelo Salese]

src/mame/audio/snes_snd.cpp

@@ -170,7 +170,6 @@ snes_sound_device::snes_sound_device(const machine_config &mconfig, const char *
 
 void snes_sound_device::device_start()
 {
-	const int timerHz[3] = { 8000, 8000, 64000 };
 	m_channel = machine().sound().stream_alloc(*this, 0, 2, 32000);
 
 	m_ram = make_unique_clear<uint8_t[]>(SNES_SPCRAM_SIZE);
@@ -178,14 +177,7 @@ void snes_sound_device::device_start()
 	/* put IPL image at the top of RAM */
 	memcpy(m_ipl_region, machine().root_device().memregion("sound_ipl")->base(), 64);
 
-	/* Initialize the timers */
+	m_tick_timer = timer_alloc(TIMER_TICK_ID);
-	for(int timerNumber=0;timerNumber<3;timerNumber++)
-	{
-		m_timer[timerNumber] = machine().scheduler().timer_alloc(timer_expired_delegate(FUNC(snes_sound_device::spc_timer),this));
-		m_timer[timerNumber]->adjust(attotime::from_hz(timerHz[timerNumber]),  0, attotime::from_hz(timerHz[timerNumber]));
-		m_timer[timerNumber]->enable(false);
-		m_TnDIV[timerNumber] = 256;
-	}
 	
 	state_register();
 	save_pointer(NAME(m_ram.get()), SNES_SPCRAM_SIZE);
@@ -197,19 +189,63 @@ void snes_sound_device::device_start()
 
 void snes_sound_device::device_reset()
 {
+	int i;
 	/* default to ROM visible */
 	m_ram[0xf1] = 0x80;
 
 	/* Sort out the ports */
-	for (int i = 0; i < 4; i++)
+	for (i = 0; i < 4; i++)
 	{
 		m_port_in[i] = 0;
 		m_port_out[i] = 0;
 	}
 
+	for(i=0; i<3; i++)
+	{
+		m_timer_enabled[i] = false;
+		m_TnDIV[i] = 256;
+		m_counter[i] = 0;
+		m_subcounter[i] = 0;
+	}
+	
+	attotime period = attotime::from_hz(64000);
+	m_tick_timer->adjust(period, 0, period);
+	
 	dsp_reset();
 }
 
+inline void snes_sound_device::update_timer_tick(uint8_t which)
+{
+	if(m_timer_enabled[which] == false)
+		return;
+	
+	m_subcounter[which]++;
+	
+	// if timer channel is 0 or 1 we update at 64000/8
+	if(m_subcounter[which] >= 8 || which == 2)
+	{
+		m_subcounter[which] = 0;
+		m_counter[which]++;
+		if (m_counter[which] >= m_TnDIV[which] ) // minus =
+		{
+			m_counter[which] = 0;
+			m_ram[0xfd + which]++;
+			m_ram[0xfd + which] &= 0x0f;
+		}
+	}
+}
+
+void snes_sound_device::device_timer(emu_timer &timer, device_timer_id id, int param, void *ptr)
+{
+	if(id != TIMER_TICK_ID)
+	{
+		assert_always(false, "Unknown id in snes_sound_device::device_timer");
+		return;
+	}
+	
+	for(int ch=0;ch<3;ch++)
+		update_timer_tick(ch);
+}
 
 
 /*****************************************************************************
@@ -986,20 +1022,6 @@ int snes_sound_device::advance_envelope( int v )
 	return envx;
 }
 
-
-TIMER_CALLBACK_MEMBER( snes_sound_device::spc_timer )
-{
-	int which = param;
-	
-	m_counter[which]++;
-	if (m_counter[which] >= m_TnDIV[which] ) // minus =
-	{
-		m_counter[which] = 0;
-		m_ram[0xfd + which]++;
-		m_ram[0xfd + which] &= 0x0f;
-	}
-}
-
 /*-------------------------------------------------
     spc700_set_volume - sets SPC700 volume level
     for both speakers, used for fade in/out effects
@@ -1097,14 +1119,15 @@ WRITE8_MEMBER( snes_sound_device::spc_io_w )
 		case 0x1:       /* Control */
 			for (int i = 0; i < 3; i++)
 			{
-				if (BIT(data, i) && !m_enabled[i])
+				if (BIT(data, i) && m_timer_enabled[i] == false)
 				{
+					m_subcounter[i] = 0;
 					m_counter[i] = 0;
 					m_ram[0xfd + i] = 0;
 				}
 
-				m_enabled[i] = BIT(data, i);
+				m_timer_enabled[i] = BIT(data, i);
-				m_timer[i]->enable(m_enabled[i]);
+				//m_timer[i]->enable(m_timer_enabled[i]);
 			}
 
 			if (BIT(data, 4))
@@ -1205,7 +1228,8 @@ void snes_sound_device::state_register()
 	save_item(NAME(m_echo_ptr));
 #endif
 
-	save_item(NAME(m_enabled));
+	save_item(NAME(m_timer_enabled));
+	save_item(NAME(m_subcounter));
 	save_item(NAME(m_counter));
 	save_item(NAME(m_port_in));
 	save_item(NAME(m_port_out));

src/mame/audio/snes_snd.h

@@ -38,6 +38,7 @@ protected:
 
 	// sound stream update overrides
 	virtual void sound_stream_update(sound_stream &stream, stream_sample_t **inputs, stream_sample_t **outputs, int samples) override;
+	virtual void device_timer(emu_timer &timer, device_timer_id id, int param, void *ptr) override;
 
 private:
 	enum class env_state_t32 : u8
@@ -82,7 +83,7 @@ private:
 
 	DECLARE_READ8_MEMBER(dsp_io_r);
 	DECLARE_WRITE8_MEMBER(dsp_io_w);
-	TIMER_CALLBACK_MEMBER(spc_timer);
+//	TIMER_CALLBACK_MEMBER(spc_timer);
 	void dsp_reset();
 	void dsp_update(short *sound_ptr);
 	int advance_envelope(int v);
@@ -110,10 +111,16 @@ private:
 	int                     m_echo_ptr;
 #endif
 
+	enum
+	{
+		TIMER_TICK_ID = 1
+	};
 	/* timers */
-	emu_timer               *m_timer[3];
+	emu_timer 				  *m_tick_timer;
-	uint8_t                   m_enabled[3];
+	bool                      m_timer_enabled[3];
 	uint16_t                  m_counter[3];
+	uint8_t					  m_subcounter[3];
+	inline void update_timer_tick(uint8_t which);
 
 	/* IO ports */
 	uint8_t                   m_port_in[4];         /* SPC input ports */