(nw) mtx : fixed cassette load

src/mame/drivers/mtx.cpp

@@ -10,7 +10,6 @@
 
     TODO:
 
-    - cassette
     - FDX floppy
     - HDX hard disk
     - HRX high resolution graphics
@@ -260,9 +259,14 @@ static const z80_daisy_config rs128_daisy_chain[] =
 
 TIMER_DEVICE_CALLBACK_MEMBER(mtx_state::cassette_tick)
 {
-	int data = ((m_cassette)->input() > +0.0) ? 0 : 1;
+	bool cass_ws = (m_cassette->input() > +0.03) ? 1 : 0;
 
-	m_z80ctc->trg3(data);
+	if (cass_ws != m_cassold)
+	{
+		m_cassold = cass_ws;
+		m_z80ctc->trg3(1);
+		m_z80ctc->trg3(0);   // this causes interrupt
+	}
 }
 
 /*-------------------------------------------------

src/mame/includes/mtx.h

@@ -29,6 +29,7 @@ class mtx_state : public driver_device
 public:
 	mtx_state(const machine_config &mconfig, device_type type, const char *tag)
 		: driver_device(mconfig, type, tag)
+		, m_cassold(0)
 		, m_maincpu(*this, "z80")
 		, m_sn(*this, "sn76489a")
 		, m_z80ctc(*this, "z80ctc")
@@ -50,6 +51,7 @@ protected:
 	virtual void machine_reset() override;
 
 private:
+	bool m_cassold;
 	required_device<z80_device> m_maincpu;
 	required_device<sn76489a_device> m_sn;
 	required_device<z80ctc_device> m_z80ctc;