casio/cps200.cpp: Added a skeleton Casio CPS-2000 driver; also improved µPD934 and MSM6200 emulation. (#13591)

* machine/msm6200.cpp: Scan matrix on a timer until a change is detected.
* sound/upd934g.cpp: Fixed play sample command.
* casio/cz1.cpp: Added MSM6200 clock input frequency.

New systems marked not working
---------------
Casio CPS-2000 [BCM, Devin Acker]

Author: devinacker

Diff for: src/devices/machine/msm6200.cpp

@@ -21,6 +21,8 @@ msm6200_device::msm6200_device(const machine_config &mconfig, const char *tag, d
 /**************************************************************************/
 void msm6200_device::device_start()
 {
+	m_timer = timer_alloc(FUNC(msm6200_device::scan_timer), this);
+
 	m_cmd = 0xf;
 
 	save_item(NAME(m_cmd));
@@ -39,6 +41,18 @@ void msm6200_device::device_reset()
 	std::fill(std::begin(m_last_state), std::end(m_last_state), 0);
 }
 
+/**************************************************************************/
+TIMER_CALLBACK_MEMBER(msm6200_device::scan_timer)
+{
+	(++m_row) %= m_keys.size();
+	m_key_state = m_keys[m_row].read_safe(0);
+	if (m_key_state != m_last_state[m_row])
+	{
+		m_irq_cb(1);
+		m_timer->adjust(attotime::never);
+	}
+}
+
 /**************************************************************************/
 void msm6200_device::write(offs_t offset, u8 data)
 {
@@ -60,30 +74,32 @@ void msm6200_device::write(offs_t offset, u8 data)
 			}
 		}
 		if (m_key_state == m_last_state[m_row])
+		{
 			m_irq_cb(0);
+			m_timer->adjust(attotime::zero, 0, attotime::from_ticks(TIMER_RATE, clock()));
+		}
 		break;
 
 	case 1: // read velocity
 		m_key_data = m_velocity.read_safe(0x3f);
 		break;
 
-	case 2: // next row?
-		(++m_row) %= m_keys.size();
+	case 2:
 		// TODO: what should this one actually be?
 		// the cz1/ht6000 key MCU code outputs the result to port 1 for debugging
 		m_key_data = m_row;
 		break;
 
-	case 7: // capture current row?
-		m_key_state = m_keys[m_row].read_safe(0);
-		if (m_key_state != m_last_state[m_row])
-			m_irq_cb(1);
+	case 7: // ?
+		// cz1/ht6000 writes this constantly, cps2000 much less frequently
 		break;
 
-	case 8: // init all rows
+	case 8: // init all rows, start scanning
 		for (int i = 0; i < m_keys.size(); i++)
 			m_last_state[i] = m_keys[i].read_safe(0);
+
 		m_irq_cb(0);
+		m_timer->adjust(attotime::zero, 0, attotime::from_ticks(TIMER_RATE, clock()));
 		break;
 
 	default:

Diff for: src/devices/machine/msm6200.h

@@ -24,11 +24,17 @@ class msm6200_device : public device_t
 	virtual void device_reset() override ATTR_COLD;
 
 private:
+	static constexpr unsigned TIMER_RATE = 256; // arbitrary
+
+	TIMER_CALLBACK_MEMBER(scan_timer);
+
 	optional_ioport_array<38> m_keys;
 	optional_ioport m_velocity;
 
 	devcb_write_line m_irq_cb;
 
+	emu_timer *m_timer;
+
 	u8 m_cmd, m_row, m_key_data;
 	u8 m_key_state;
 	u8 m_last_state[38];

Diff for: src/devices/sound/upd934g.cpp

@@ -53,7 +53,8 @@ void upd934g_device::device_start()
 	m_stream = stream_alloc(0, 4, 20000);
 
 	// register for save states
-	save_pointer(NAME(m_addr), 16);
+	save_item(NAME(m_addr));
+	save_item(NAME(m_valid));
 
 	save_item(STRUCT_MEMBER(m_channel, pos));
 	save_item(STRUCT_MEMBER(m_channel, playing));
@@ -71,8 +72,15 @@ void upd934g_device::device_reset()
 {
 	m_ready = false;
 
+	for (unsigned i = 0; i < 16; i++)
+		m_addr[i] = m_valid[i] = 0;
+
 	for (unsigned i = 0; i < 4; i++)
+	{
+		m_channel[i].pos = 0;
 		m_channel[i].playing = -1;
+		m_channel[i].effect = 0;
+	}
 }
 
 //-------------------------------------------------
@@ -86,14 +94,15 @@ void upd934g_device::sound_stream_update(sound_stream &stream, std::vector<read_
 	{
 		if (m_ready && m_channel[ch].playing != -1)
 		{
-			uint16_t end = m_addr[m_channel[ch].playing + 1] - 1;
+			uint16_t end = m_addr[(m_channel[ch].playing + 1) & 0xf] - 1;
 
 			for (unsigned i = 0; i < outputs[ch].samples(); i++)
 			{
 				int16_t raw = static_cast<int8_t>(read_byte(m_channel[ch].pos)) * 4;
 
 				// normal, muted, accented
-				const double adjust[] = { 0, 0.7, 0.4, 1.0 };
+				// TODO: cps2000 regularly sets effect bits to 0 instead of 2 - are these the same?
+				const double adjust[] = { 0.4, 0.7, 0.4, 1.0 };
 				raw *= adjust[m_channel[ch].effect];
 
 				outputs[ch].put_int(i, raw, 32768 / 64);
@@ -118,38 +127,34 @@ void upd934g_device::sound_stream_update(sound_stream &stream, std::vector<read_
 
 void upd934g_device::write(offs_t offset, uint8_t data)
 {
-	switch (offset)
+	switch (offset & 3)
 	{
 	case 0:
 		// format of data written here is:
-		// 76------  command
+		// 76------  effect
 		// --5432--  sample number
 		// ------10  output channel
 		m_sample = (data >> 2) & 0x0f;
 
-		switch (data >> 6)
+		// don't play a sample unless we're sure it's actually supposed to play:
+		// - all models write this with effect=0 to select which sample to set the address of
+		// - cps2000 writes this with effect=0 to play muted(?) samples
+		// - cps2000 also writes this with effect=1 and sample=f on boot even though there are only 12 valid samples
+		if (m_valid[m_sample])
 		{
-		case 0:
-			LOG("CMD STORE ADDRESS sample %x\n", m_sample);
-			break;
-		case 1: // normal
-		case 2: // muted
-		case 3: // accented
-			{
-				const u8 ch = (data & 3) ^ 2; // effective order seems to be "2, 3, 0, 1"
-				LOG("CMD PLAY sample %x (channel %d, effect %d)\n", m_sample, ch, data >> 6);
-				m_channel[ch].pos = m_addr[m_sample];
-				m_channel[ch].playing = m_sample;
-				m_channel[ch].effect = data >> 6;
-			}
-			break;
+			const u8 ch = (data & 3) ^ 2; // effective order seems to be "2, 3, 0, 1"
+			LOG("CMD PLAY sample %x (channel %d, effect %d)\n", m_sample, ch, data >> 6);
+			m_channel[ch].pos = m_addr[m_sample];
+			m_channel[ch].playing = m_sample;
+			m_channel[ch].effect = data >> 6;
 		}
 		break;
 	case 1:
 		m_addr[m_sample] = (m_addr[m_sample] & 0xff00) | (data << 0);
 		break;
 	case 2:
 		m_addr[m_sample] = (m_addr[m_sample] & 0x00ff) | (data << 8);
+		m_valid[m_sample] = 1;
 		LOG("  sample %x address = %04x\n", m_sample, m_addr[m_sample]);
 		break;
 	case 3:

Diff for: src/devices/sound/upd934g.h

@@ -27,7 +27,7 @@ class upd934g_device : public device_t, public device_sound_interface, public de
 	// construction/destruction
 	upd934g_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock);
 
-	void write(offs_t offset, uint8_t data);
+	void write(offs_t offset, u8 data);
 
 protected:
 	// device-level overrides
@@ -39,18 +39,19 @@ class upd934g_device : public device_t, public device_sound_interface, public de
 private:
 	sound_stream *m_stream;
 
-	uint16_t m_addr[16];
+	u16 m_addr[16];
+	u8 m_valid[16];
 
 	struct
 	{
-		uint16_t pos;
-		int playing;
-		int effect;
+		u16 pos;
+		s8 playing;
+		u8 effect;
 	}
 	m_channel[4];
 
-	int m_sample;
-	bool m_ready;
+	u8 m_sample;
+	u8 m_ready;
 };
 
 // device type definition

Diff for: src/emu/xtal.cpp

@@ -83,6 +83,7 @@ const double XTAL::known_xtals[] = {
 	  2'250'000, // 2.25_MHz_XTAL          Resonator - YM2154 on Yamaha PSR-60 & PSR-70
 	  2'376'000, // 2.376_MHz_XTAL         CIT-101 keyboard
 	  2'457'600, // 2.4576_MHz_XTAL        Atari ST MFP
+	  2'470'000, // 2.47_MHz_XTAL          CSA2.47MG ceramic oscillator - Casio CZ-1
 	  2'500'000, // 2.5_MHz_XTAL           Janken Man units
 	  2'600'000, // 2.6_MHz_XTAL           Sharp PC-1500
 	  2'700'000, // 2.7_MHz_XTAL           Resonator - YM2154 on Yamaha RX15
@@ -119,6 +120,7 @@ const double XTAL::known_xtals[] = {
 	  4'433'619, // 4.433619_MHz_XTAL      PAL color subcarrier (technically 4.43361875mhz)
 	  4'608'000, // 4.608_MHz_XTAL         Luxor ABC-77 keyboard (Keytronic custom part #48-300-107 is equivalent)
 	  4'915'200, // 4.9152_MHz_XTAL        -
+	  4'946'800, // 4.9468_MHz_XTAL        Casio CPS-2000
 	  4'946'864, // 4.946864_MHz_XTAL      Casiotone 8000
 	  4'952'000, // 4.952_MHz_XTAL         IGS M036 based mahjong games, for TT5665 sound chip
 	  5'000'000, // 5_MHz_XTAL             Mutant Night