cosmac: add very preliminary 1804/5/6 (nw)

src/devices/cpu/cosmac/cosmac.cpp

@@ -4,6 +4,13 @@
 
 RCA COSMAC CPU emulation
 
+TODO:
+- is it useful to emulate I and N registers or can they just be defined as (m_op >> x & 0xf)?
+- 1804/5/6: extended opcode timing is wrong, multiple execute states
+- 1804/5/6: add more extended opcodes (05/06 supports more than 04)
+- 1804/5/6: add counter/timer
+- 1804/5: add internal address map (ram/rom)
+
 **********************************************************************/
 
 #include "emu.h"
@@ -150,9 +157,9 @@ const cosmac_device::ophandler cdp1801_device::s_opcodetable[256] =
 	&cdp1801_device::adi,    &cdp1801_device::sdi,    &cdp1801_device::und,    &cdp1801_device::smi
 };
 
-cosmac_device::ophandler cdp1801_device::get_ophandler(uint8_t opcode) const
+cosmac_device::ophandler cdp1801_device::get_ophandler(uint16_t opcode) const
 {
-	return s_opcodetable[opcode];
+	return s_opcodetable[opcode & 0xff];
 }
 
 const cosmac_device::ophandler cdp1802_device::s_opcodetable[256] =
@@ -238,9 +245,100 @@ const cosmac_device::ophandler cdp1802_device::s_opcodetable[256] =
 	&cdp1802_device::adi,    &cdp1802_device::sdi,    &cdp1802_device::shl,    &cdp1802_device::smi
 };
 
-cosmac_device::ophandler cdp1802_device::get_ophandler(uint8_t opcode) const
+cosmac_device::ophandler cdp1802_device::get_ophandler(uint16_t opcode) const
 {
-	return s_opcodetable[opcode];
+	return s_opcodetable[opcode & 0xff];
+}
+
+const cosmac_device::ophandler cdp1804_device::s_opcodetable_ex[256] =
+{
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::ldc,    &cdp1804_device::und,
+	&cdp1804_device::gec,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::bci,    &cdp1804_device::bxi,
+
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+
+	&cdp1804_device::rlxa,   &cdp1804_device::rlxa,   &cdp1804_device::rlxa,   &cdp1804_device::rlxa,
+	&cdp1804_device::rlxa,   &cdp1804_device::rlxa,   &cdp1804_device::rlxa,   &cdp1804_device::rlxa,
+	&cdp1804_device::rlxa,   &cdp1804_device::rlxa,   &cdp1804_device::rlxa,   &cdp1804_device::rlxa,
+	&cdp1804_device::rlxa,   &cdp1804_device::rlxa,   &cdp1804_device::rlxa,   &cdp1804_device::rlxa,
+
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+
+	&cdp1804_device::rsxd,   &cdp1804_device::rsxd,   &cdp1804_device::rsxd,   &cdp1804_device::rsxd,
+	&cdp1804_device::rsxd,   &cdp1804_device::rsxd,   &cdp1804_device::rsxd,   &cdp1804_device::rsxd,
+	&cdp1804_device::rsxd,   &cdp1804_device::rsxd,   &cdp1804_device::rsxd,   &cdp1804_device::rsxd,
+	&cdp1804_device::rsxd,   &cdp1804_device::rsxd,   &cdp1804_device::rsxd,   &cdp1804_device::rsxd,
+
+	&cdp1804_device::rnx,    &cdp1804_device::rnx,    &cdp1804_device::rnx,    &cdp1804_device::rnx,
+	&cdp1804_device::rnx,    &cdp1804_device::rnx,    &cdp1804_device::rnx,    &cdp1804_device::rnx,
+	&cdp1804_device::rnx,    &cdp1804_device::rnx,    &cdp1804_device::rnx,    &cdp1804_device::rnx,
+	&cdp1804_device::rnx,    &cdp1804_device::rnx,    &cdp1804_device::rnx,    &cdp1804_device::rnx,
+
+	&cdp1804_device::rldi,   &cdp1804_device::rldi,   &cdp1804_device::rldi,   &cdp1804_device::rldi,
+	&cdp1804_device::rldi,   &cdp1804_device::rldi,   &cdp1804_device::rldi,   &cdp1804_device::rldi,
+	&cdp1804_device::rldi,   &cdp1804_device::rldi,   &cdp1804_device::rldi,   &cdp1804_device::rldi,
+	&cdp1804_device::rldi,   &cdp1804_device::rldi,   &cdp1804_device::rldi,   &cdp1804_device::rldi,
+
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+	&cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,    &cdp1804_device::und,
+};
+
+cosmac_device::ophandler cdp1804_device::get_ophandler(uint16_t opcode) const
+{
+	if ((opcode & 0xff00) == 0x6800)
+		return s_opcodetable_ex[opcode & 0xff];
+	else
+		return cdp1802_device::get_ophandler(opcode);
 }
 
 
@@ -252,6 +350,9 @@ cosmac_device::ophandler cdp1802_device::get_ophandler(uint8_t opcode) const
 // device type definition
 DEFINE_DEVICE_TYPE(CDP1801, cdp1801_device, "cdp1801", "RCA CDP1801")
 DEFINE_DEVICE_TYPE(CDP1802, cdp1802_device, "cdp1802", "RCA CDP1802")
+DEFINE_DEVICE_TYPE(CDP1804, cdp1804_device, "cdp1804", "RCA CDP1804")
+DEFINE_DEVICE_TYPE(CDP1805, cdp1805_device, "cdp1805", "RCA CDP1805")
+DEFINE_DEVICE_TYPE(CDP1806, cdp1806_device, "cdp1806", "RCA CDP1806")
 
 
 //-------------------------------------------------
@@ -294,20 +395,57 @@ cosmac_device::cosmac_device(const machine_config &mconfig, device_type type, co
 //  cdp1801_device - constructor
 //-------------------------------------------------
 
-cdp1801_device::cdp1801_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock)
+cdp1801_device::cdp1801_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock) :
-	: cosmac_device(mconfig, CDP1801, tag, owner, clock)
+	cosmac_device(mconfig, CDP1801, tag, owner, clock)
-{
+{ }
-}
 
 
 //-------------------------------------------------
 //  cdp1802_device - constructor
 //-------------------------------------------------
 
-cdp1802_device::cdp1802_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock)
+cdp1802_device::cdp1802_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock) :
-	: cosmac_device(mconfig, CDP1802, tag, owner, clock)
+	cdp1802_device(mconfig, CDP1802, tag, owner, clock)
-{
+{ }
-}
+
+cdp1802_device::cdp1802_device(const machine_config &mconfig, device_type type, const char *tag, device_t *owner, uint32_t clock) :
+	cosmac_device(mconfig, type, tag, owner, clock)
+{ }
+
+
+//-------------------------------------------------
+//  cdp1804_device - constructor
+//-------------------------------------------------
+
+cdp1804_device::cdp1804_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock) :
+	cdp1804_device(mconfig, CDP1804, tag, owner, clock)
+{ }
+
+cdp1804_device::cdp1804_device(const machine_config &mconfig, device_type type, const char *tag, device_t *owner, uint32_t clock) :
+	cdp1802_device(mconfig, type, tag, owner, clock)
+{ }
+
+
+//-------------------------------------------------
+//  cdp1805_device - constructor
+//-------------------------------------------------
+
+cdp1805_device::cdp1805_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock) :
+	cdp1805_device(mconfig, CDP1805, tag, owner, clock)
+{ }
+
+cdp1805_device::cdp1805_device(const machine_config &mconfig, device_type type, const char *tag, device_t *owner, uint32_t clock) :
+	cdp1804_device(mconfig, type, tag, owner, clock)
+{ }
+
+
+//-------------------------------------------------
+//  cdp1806_device - constructor
+//-------------------------------------------------
+
+cdp1806_device::cdp1806_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock) :
+	cdp1805_device(mconfig, CDP1806, tag, owner, clock)
+{ }
 
 
 //-------------------------------------------------
@@ -717,6 +855,9 @@ inline void cosmac_device::run_state()
 	switch (m_state)
 	{
 	case cosmac_state::STATE_0_FETCH:
+		m_op = 0;
+
+	case cosmac_state::STATE_0_FETCH_2ND:
 		fetch_instruction();
 		break;
 
@@ -795,7 +936,7 @@ inline void cosmac_device::sample_ef_lines()
 
 inline void cosmac_device::output_state_code()
 {
-	if (m_state == cosmac_state::STATE_0_FETCH)
+	if (m_state == cosmac_state::STATE_0_FETCH || m_state == cosmac_state::STATE_0_FETCH_2ND)
 	{
 		// S0 fetch
 		m_write_sc(0, COSMAC_STATE_CODE_S0_FETCH);
@@ -813,13 +954,13 @@ inline void cosmac_device::output_state_code()
 	else
 	{
 		// S1 execute
-		m_write_sc(I == 0x6 ? (N & 7) : 0, COSMAC_STATE_CODE_S1_EXECUTE);
+		m_write_sc((m_op >> 4) == 0x6 ? (N & 7) : 0, COSMAC_STATE_CODE_S1_EXECUTE);
 	}
 }
 
 void cdp1801_device::output_state_code()
 {
-	if (m_state == cosmac_state::STATE_0_FETCH)
+	if (m_state == cosmac_state::STATE_0_FETCH || m_state == cosmac_state::STATE_0_FETCH_2ND)
 	{
 		// S0 fetch
 		m_write_sc(0, 4);
@@ -834,7 +975,7 @@ void cdp1801_device::output_state_code()
 		// S3 interrupt
 		m_write_sc(0, 3);
 	}
-	else if (I == 0x6)
+	else if ((m_op >> 4) == 0x6)
 	{
 		// S1 execute (I/O)
 		m_write_sc(N, 1);
@@ -889,14 +1030,18 @@ inline void cosmac_device::fetch_instruction()
 	// instruction fetch
 	offs_t addr = R[P]++;
 	m_write_tpb(1);
-	m_op = read_opcode(addr);
+	m_op = m_op << 8 | read_opcode(addr);
 	m_write_tpb(0);
 
-	I = m_op >> 4;
+	I = m_op >> 4 & 0x0f;
 	N = m_op & 0x0f;
 
 	m_icount -= CLOCKS_FETCH;
 
+	// CDP1804 and up: 0x68 for extended opcodes
+	if (m_op == 0x68 && has_extended_opcodes())
+		m_state = cosmac_state::STATE_0_FETCH_2ND;
+	else
 		m_state = cosmac_state::STATE_1_EXECUTE;
 }
 
@@ -963,7 +1108,7 @@ inline void cosmac_device::execute_instruction()
 
 	m_icount -= CLOCKS_EXECUTE;
 
-	if (I == 0xc && m_state == cosmac_state::STATE_1_EXECUTE)
+	if (m_state == cosmac_state::STATE_1_EXECUTE && (m_op >> 4) == 0xc) // "long" opcodes
 	{
 		m_state = cosmac_state::STATE_1_EXECUTE_2ND;
 	}
@@ -979,7 +1124,7 @@ inline void cosmac_device::execute_instruction()
 	{
 		m_state = cosmac_state::STATE_3_INT;
 	}
-	else if ((I > 0) || (N > 0)) // not idling
+	else if (m_op != 0) // not idling
 	{
 		m_state = cosmac_state::STATE_0_FETCH;
 	}
@@ -1298,3 +1443,16 @@ void cosmac_device::out()   { IO_W(N, RAM_R(R[X])); R[X]++; }
 
 */
 void cosmac_device::inp()   { D = IO_R(N & 0x07); RAM_W(R[X], D); }
+
+// CDP1804(and up) extended opcodes
+void cosmac_device::rldi()  { put_high_reg(N, RAM_R(R[P])); R[P]++; put_low_reg(N, RAM_R(R[P])); R[P]++; }
+void cosmac_device::rlxa()  { put_high_reg(N, RAM_R(R[X])); R[X]++; put_low_reg(N, RAM_R(R[X])); R[X]++; }
+void cosmac_device::rsxd()  { RAM_W(R[X], R[N] >> 0 & 0xff); R[X]--; RAM_W(R[X], R[N] >> 8 & 0xff); R[X]--; }
+
+void cosmac_device::rnx()   { R[X] = R[N]; }
+
+void cosmac_device::bci()   { short_branch(1); } // wrong! tests CI flag
+void cosmac_device::bxi()   { short_branch(0); } // wrong! tests XI flag
+
+void cosmac_device::ldc()   { /* logerror("LDC counter set: %X\n", D); */ }
+void cosmac_device::gec()   { D = machine().rand() & 0xf; } // wrong!

src/devices/cpu/cosmac/cosmac.h

@@ -69,7 +69,7 @@
     Type            Internal ROM    Internal RAM    Timer   Pin 16 (*)
     ------------------------------------------------------------------
     CDP1802         none            none            no          Vcc
-    CDP1803         ?               ?               ?           ?
+    CDP1803         ?               ?               ?           ?       does not exist?
     CDP1804         2 KB            64 bytes        yes         ?
     CDP1805         none            64 bytes        yes         _ME
     CDP1806         none            none            yes         Vdd
@@ -333,6 +333,16 @@ protected:
 	void out();
 	void inp();
 
+	// extended opcodes
+	void rldi();
+	void rlxa();
+	void rsxd();
+	void rnx();
+	void bci();
+	void bxi();
+	void ldc();
+	void gec();
+
 	const address_space_config      m_program_config;
 	const address_space_config      m_io_config;
 
@@ -359,6 +369,7 @@ protected:
 	enum class cosmac_state : u8
 	{
 		STATE_0_FETCH = 0,
+		STATE_0_FETCH_2ND,
 		STATE_1_INIT,
 		STATE_1_EXECUTE,
 		STATE_1_EXECUTE_2ND,
@@ -369,7 +380,7 @@ protected:
 
 	// internal state
 	uint16_t              m_pc;               // fake program counter
-	uint8_t               m_op;               // current opcode
+	uint16_t              m_op;               // current opcode
 	uint8_t               m_flagsio;          // flags storage for state saving
 	cosmac_state        m_state;            // state
 	cosmac_mode         m_mode;             // control mode
@@ -405,7 +416,8 @@ protected:
 
 	// opcode/condition tables
 	typedef void (cosmac_device::*ophandler)();
-	virtual cosmac_device::ophandler get_ophandler(uint8_t opcode) const = 0;
+	virtual cosmac_device::ophandler get_ophandler(uint16_t opcode) const = 0;
+	virtual bool has_extended_opcodes() { return false; }
 };
 
 
@@ -421,10 +433,11 @@ protected:
 	// device_disasm_interface overrides
 	virtual std::unique_ptr<util::disasm_interface> create_disassembler() override;
 
-	virtual cosmac_device::ophandler get_ophandler(uint8_t opcode) const override;
+	virtual cosmac_device::ophandler get_ophandler(uint16_t opcode) const override;
 
 	virtual void output_state_code() override;
 
+private:
 	static const ophandler s_opcodetable[256];
 };
 
@@ -438,18 +451,66 @@ public:
 	cdp1802_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock);
 
 protected:
+	cdp1802_device(const machine_config &mconfig, device_type type, const char *tag, device_t *owner, uint32_t clock);
+
 	// device_disasm_interface overrides
 	virtual std::unique_ptr<util::disasm_interface> create_disassembler() override;
 
-	virtual cosmac_device::ophandler get_ophandler(uint8_t opcode) const override;
+	virtual cosmac_device::ophandler get_ophandler(uint16_t opcode) const override;
 
+private:
 	static const ophandler s_opcodetable[256];
 };
 
 
+// ======================> cdp1804_device
+
+class cdp1804_device : public cdp1802_device
+{
+public:
+	// construction/destruction
+	cdp1804_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock);
+
+protected:
+	cdp1804_device(const machine_config &mconfig, device_type type, const char *tag, device_t *owner, uint32_t clock);
+
+	virtual cosmac_device::ophandler get_ophandler(uint16_t opcode) const override;
+	virtual bool has_extended_opcodes() override { return true; }
+
+private:
+	static const ophandler s_opcodetable_ex[256];
+};
+
+
+// ======================> cdp1805_device
+
+class cdp1805_device : public cdp1804_device
+{
+public:
+	// construction/destruction
+	cdp1805_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock);
+
+protected:
+	cdp1805_device(const machine_config &mconfig, device_type type, const char *tag, device_t *owner, uint32_t clock);
+};
+
+
+// ======================> cdp1806_device
+
+class cdp1806_device : public cdp1805_device
+{
+public:
+	// construction/destruction
+	cdp1806_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock);
+};
+
+
 // device type definition
 DECLARE_DEVICE_TYPE(CDP1801, cdp1801_device)
 DECLARE_DEVICE_TYPE(CDP1802, cdp1802_device)
+DECLARE_DEVICE_TYPE(CDP1804, cdp1804_device)
+DECLARE_DEVICE_TYPE(CDP1805, cdp1805_device)
+DECLARE_DEVICE_TYPE(CDP1806, cdp1806_device)
 
 
 #endif // MAME_CPU_COSMAC_COSMAC_H

src/mame/drivers/mephisto_mm1.cpp

@@ -28,9 +28,9 @@ expensive wooden chessboards like Modular Exclusive or Muenchen, as long as it
 supports the higher voltage.
 
 TODO:
-- doesn't work, MAME doesn't emulate 1806 CPU (it uses RLDI, RLXA, RSXD, and
+- remove external interrupt hack when timer interrupt is added to CDP1806 device
-  counter interrupt opcodes)
 - mmirage unknown_w
+- mm1 unknown expansion rom at $c000?
 - add mm1 opening book
 - add mm1 STP/ON buttons? (they're off/on, with RAM chips remaining powered)
 
@@ -74,7 +74,7 @@ protected:
 
 private:
 	// devices/pointers
-	required_device<cdp1802_device> m_maincpu;
+	required_device<cdp1806_device> m_maincpu;
 	required_device<sensorboard_device> m_board;
 	required_device<pwm_display_device> m_display;
 	required_device<dac_bit_interface> m_dac;
@@ -256,7 +256,8 @@ void mm1_state::mirage_map(address_map &map)
 void mm1_state::mm1_map(address_map &map)
 {
 	mirage_map(map);
-	map(0xc000, 0xcfff).unmapr(); // bookrom?
+	map(0x8000, 0xbfff).unmapr(); // bookrom?
+	map(0xc000, 0xc000).nopr(); // looks for $c0, jumps to $c003 if true
 }
 
 void mm1_state::mm1_io(address_map &map)
@@ -345,8 +346,8 @@ static INPUT_PORTS_START( mirage )
 
 	PORT_START("FAKE") // module came with buttons sensorboard by default
 	PORT_CONFNAME( 0x01, 0x00, "Board Sensors" ) PORT_CHANGED_MEMBER(DEVICE_SELF, mm1_state, mirage_switch_sensor_type, nullptr)
-	PORT_CONFSETTING(    0x00, "Buttons" )
+	PORT_CONFSETTING(    0x00, "Buttons (Mirage)" )
-	PORT_CONFSETTING(    0x01, "Magnets" )
+	PORT_CONFSETTING(    0x01, "Magnets (Modular)" )
 INPUT_PORTS_END
 
 INPUT_CHANGED_MEMBER(mm1_state::mirage_switch_sensor_type)
@@ -363,7 +364,7 @@ INPUT_CHANGED_MEMBER(mm1_state::mirage_switch_sensor_type)
 void mm1_state::mirage(machine_config &config)
 {
 	/* basic machine hardware */
-	CDP1802(config, m_maincpu, 8_MHz_XTAL);
+	CDP1806(config, m_maincpu, 8_MHz_XTAL);
 	m_maincpu->set_addrmap(AS_PROGRAM, &mm1_state::mirage_map);
 	m_maincpu->set_addrmap(AS_IO, &mm1_state::mm1_io);
 	m_maincpu->clear_cb().set(FUNC(mm1_state::clear_r));
@@ -371,7 +372,9 @@ void mm1_state::mirage(machine_config &config)
 	m_maincpu->ef3_cb().set(FUNC(mm1_state::keypad_r<0>));
 	m_maincpu->ef4_cb().set(FUNC(mm1_state::keypad_r<1>));
 
-	m_maincpu->set_periodic_int(FUNC(mm1_state::interrupt), attotime::from_hz(150)); // fake
+	// wrong! uses internal timer interrupt
+	const attotime irq_period = attotime::from_ticks(8 * 32 * 0x71, 8_MHz_XTAL); // LDC = 0x71
+	m_maincpu->set_periodic_int(FUNC(mm1_state::interrupt), irq_period);
 
 	SENSORBOARD(config, m_board).set_type(sensorboard_device::BUTTONS);
 	m_board->init_cb().set(m_board, FUNC(sensorboard_device::preset_chess));
@@ -396,6 +399,10 @@ void mm1_state::mm1(machine_config &config)
 	m_maincpu->set_addrmap(AS_PROGRAM, &mm1_state::mm1_map);
 	m_maincpu->q_cb().set(FUNC(mm1_state::q_w));
 
+	// wrong! uses internal timer interrupt
+	const attotime irq_period = attotime::from_ticks(8 * 32 * 0xfa, 8_MHz_XTAL); // LDC = 0xFA
+	m_maincpu->set_periodic_int(FUNC(mm1_state::interrupt), irq_period);
+
 	m_board->set_type(sensorboard_device::MAGNETS);
 }