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// license:BSD-3-Clause
// copyright-holders:R. Belmont, Olivier Galibert
/*
    Mitsubishi M5074x 8-bit microcontroller family
*/

#include "emu.h"
#include "m5074x.h"

//**************************************************************************
//  MACROS / CONSTANTS
//**************************************************************************

#define IRQ_CNTRREQ (0x80)
#define IRQ_CNTRENA (0x40)
#define IRQ_TMR1REQ (0x20)
#define IRQ_TMR1ENA (0x10)
#define IRQ_TMR2REQ (0x08)
#define IRQ_TMR2ENA (0x04)
#define IRQ_INTREQ  (0x02)
#define IRQ_INTENA  (0x01)

#define TMRC_TMRXREQ (0x80)
#define TMRC_TMRXENA (0x40)
#define TMRC_TMRXHLT (0x20)
#define TMRC_TMRXMDE (0x0c)

//**************************************************************************
//  DEVICE DEFINITIONS
//**************************************************************************

const device_type M50740 = &device_creator<m50740_device>;
const device_type M50741 = &device_creator<m50741_device>;

//**************************************************************************
//  LIVE DEVICE
//**************************************************************************

//-------------------------------------------------
//  m5074x_device - constructor
//-------------------------------------------------
m5074x_device::m5074x_device(const machine_config &mconfig, device_type type, const char *name, const char *tag, device_t *owner, UINT32 clock, address_map_constructor internal_map, const char *shortname, const char *source) :
	m740_device(mconfig, type, name, tag, owner, clock, shortname, source),
	m_program_config("program", ENDIANNESS_LITTLE, 8, 13, 0, internal_map),
	read_p0(*this),
	read_p1(*this),
	read_p2(*this),
	read_p3(*this),
	write_p0(*this),
	write_p1(*this),
	write_p2(*this),
	write_p3(*this),
	m_intctrl(0),
	m_tmrctrl(0),
	m_tmr12pre(0),
	m_tmr1(0),
	m_tmr2(0),
	m_tmrxpre(0),
	m_tmrx(0),
	m_tmr1latch(0),
	m_tmr2latch(0),
	m_tmrxlatch(0),
	m_last_all_ints(0)
{
}

//-------------------------------------------------
//  device_start - device-specific startup
//-------------------------------------------------

void m5074x_device::device_start()
{
	read_p0.resolve_safe(0);
	read_p1.resolve_safe(0);
	read_p2.resolve_safe(0);
	read_p3.resolve_safe(0);
	write_p0.resolve_safe();
	write_p1.resolve_safe();
	write_p2.resolve_safe();
	write_p3.resolve_safe();

	for (int i = 0; i < NUM_TIMERS; i++)
	{
		m_timers[i] = timer_alloc(i, NULL);
	}

	m740_device::device_start();

	save_item(NAME(m_ports));
	save_item(NAME(m_ddrs));
	save_item(NAME(m_intctrl));
	save_item(NAME(m_tmrctrl));
	save_item(NAME(m_tmr12pre));
	save_item(NAME(m_tmr1));
	save_item(NAME(m_tmr2));
	save_item(NAME(m_tmrxpre));
	save_item(NAME(m_tmrx));
	save_item(NAME(m_tmr1latch));
	save_item(NAME(m_tmr2latch));
	save_item(NAME(m_tmrxlatch));
	save_item(NAME(m_last_all_ints));

	memset(m_ports, 0, sizeof(m_ports));
	memset(m_ddrs, 0, sizeof(m_ddrs));
	m_intctrl = m_tmrctrl = 0;
	m_tmr12pre = m_tmrxpre = 0;
	m_tmr1 = m_tmr2 = m_tmrx = 0;
	m_last_all_ints = 0;
}


//-------------------------------------------------
//  device_reset - device-specific reset
//-------------------------------------------------

void m5074x_device::device_reset()
{
	m740_device::device_reset();

	// all ports reset to input on startup
	memset(m_ports, 0, sizeof(m_ports));
	memset(m_ddrs, 0, sizeof(m_ddrs));
	m_intctrl = m_tmrctrl = 0;
	m_tmr12pre = m_tmrxpre = 0;
	m_tmr1 = m_tmr2 = m_tmrx = 0;
}

void m5074x_device::device_timer(emu_timer &timer, device_timer_id id, int param, void *ptr)
{
	switch (id)
	{
		case TIMER_1:
			m_tmr1--;

			if (m_tmr1 <= 0)
			{
				m_intctrl |= IRQ_TMR1REQ;
				m_tmr1 = m_tmr1latch;
				recalc_irqs();
			}
			break;

		case TIMER_2:
			m_tmr2--;

			if (m_tmr2 <= 0)
			{
				m_intctrl |= IRQ_TMR2REQ;
				m_tmr2 = m_tmr2latch;
				recalc_irqs();
			}
			break;

		case TIMER_X:
			m_tmrx--;

			if (m_tmrx <= 0)
			{
				m_tmrctrl |= TMRC_TMRXREQ;
				m_tmrx = m_tmrxlatch;
				recalc_irqs();
			}
			break;
	}
}

void m5074x_device::execute_set_input(int inputnum, int state)
{
	switch (inputnum)
	{
		case M5074X_INT1_LINE:
			if (state == ASSERT_LINE)
			{
				m_intctrl |= IRQ_INTREQ;
			}
			else
			{
				m_intctrl &= ~IRQ_INTREQ;
			}
			break;

		case M5074X_SET_OVERFLOW:   // the base 740 class can handle this
			m740_device::execute_set_input(M740_SET_OVERFLOW, state);
			break;
	}

	recalc_irqs();
}

void m5074x_device::recalc_irqs()
{
	UINT8 all_ints = 0;

	if ((m_intctrl & (IRQ_CNTRREQ|IRQ_CNTRENA)) == (IRQ_CNTRREQ|IRQ_CNTRENA))
	{
		all_ints |= 0x01;
	}
	if ((m_tmrctrl & (TMRC_TMRXREQ|TMRC_TMRXENA)) == (TMRC_TMRXREQ|TMRC_TMRXENA))
	{
		all_ints |= 0x02;
	}
	if ((m_intctrl & (IRQ_TMR1REQ|IRQ_TMR1ENA)) == (IRQ_TMR1REQ|IRQ_TMR1ENA))
	{
		all_ints |= 0x04;
	}
	if ((m_intctrl & (IRQ_TMR2REQ|IRQ_TMR2ENA)) == (IRQ_TMR2REQ|IRQ_TMR2ENA))
	{
		all_ints |= 0x08;
	}
	if ((m_intctrl & (IRQ_INTREQ|IRQ_INTENA)) == (IRQ_INTREQ|IRQ_INTENA))
	{
		all_ints |= 0x10;
	}

	// check all 5 IRQ bits for changes
	for (int i = 0; i < 5; i++)
	{
		// if bit is set now
		if (all_ints & (1 << i))
		{
			// and wasn't last time
			if (!(m_last_all_ints & (1 << i)))
			{
				m740_device::execute_set_input(M740_INT0_LINE + i, ASSERT_LINE);
			}
		}
		else    // bit is clear now
		{
			// ...and wasn't clear last time
			if (m_last_all_ints & (1 << i))
			{
				m740_device::execute_set_input(M740_INT0_LINE + i, CLEAR_LINE);
			}
		}
	}

	m_last_all_ints = all_ints;
}

void m5074x_device::recalc_timer(int timer)
{
	int hz;

	switch (timer)
	{
		case 0:
			hz = clock() / 16;
			hz /= (m_tmr12pre + 2);
			m_timers[TIMER_1]->adjust(attotime::from_hz(hz), 0, attotime::from_hz(hz));
			break;

		case 1:
			hz = clock() / 16;
			hz /= (m_tmr12pre + 2);
			m_timers[TIMER_2]->adjust(attotime::from_hz(hz), 0, attotime::from_hz(hz));
			break;

		case 2:
			// Timer X modes: 00 = free run countdown, 01 = invert CNTR pin each time expires,
			// 10 = count each time CNTR pin inverts, 11 = count when CNTR pin low
			if ((m_tmrctrl & TMRC_TMRXMDE) == 0)
			{
				// stop bit?
				if (m_tmrctrl & TMRC_TMRXHLT)
				{
					m_timers[TIMER_X]->adjust(attotime::never, 0, attotime::never);
				}
				else
				{
					hz = clock() / 16;
					hz /= (m_tmrxpre + 2);
					m_timers[TIMER_X]->adjust(attotime::from_hz(hz), 0, attotime::from_hz(hz));
				}
			}
			else
			{
				fatalerror("M5074x: Unhandled timer X mode %d\n", (m_tmrctrl&TMRC_TMRXMDE)>>2);
			}
			break;
	}
}

void m5074x_device::send_port(address_space &space, UINT8 offset, UINT8 data)
{
	switch (offset)
	{
		case 0:
			write_p0(data);
			break;

		case 1:
			write_p1(data);
			break;

		case 2:
			write_p2(data);
			break;

		case 3:
			write_p3(data);
			break;
	}
}

UINT8 m5074x_device::read_port(UINT8 offset)
{
	UINT8 incoming = 0;

	switch (offset)
	{
		case 0:
			incoming = read_p0();
			break;

		case 1:
			incoming = read_p1();
			break;

		case 2:
			incoming = read_p2();
			break;

		case 3:
			incoming = read_p3();
			break;
	}

	// apply data direction registers
	incoming &= (m_ddrs[offset] ^ 0xff);
	// OR in ddr-masked version of port writes
	incoming |= (m_ports[offset] & m_ddrs[offset]);

	return incoming;
}

READ8_MEMBER(m5074x_device::ports_r)
{
	switch (offset)
	{
		case 0:
			return read_port(0);

		case 1:
			return m_ddrs[0];

		case 2:
			return read_port(1);

		case 3:
			return m_ddrs[1];

		case 4:
			return read_port(2);

		case 5:
			return m_ddrs[2];

		case 8:
			return read_port(3);

		case 9:
			return m_ddrs[3];
	}

	return 0xff;
}

WRITE8_MEMBER(m5074x_device::ports_w)
{
	switch (offset)
	{
		case 0: // p0
			send_port(space, 0, data & m_ddrs[0]);
			m_ports[0] = data;
			break;

		case 1: // p0 ddr
			send_port(space, 0, m_ports[0] & data);
			m_ddrs[0] = data;
			break;

		case 2: // p1
			send_port(space, 1, data & m_ddrs[1]);
			m_ports[1] = data;
			break;

		case 3: // p1 ddr
			send_port(space, 1, m_ports[1] & data);
			m_ddrs[1] = data;
			break;

		case 4: // p2
			send_port(space, 2, data & m_ddrs[2]);
			m_ports[2] = data;
			break;

		case 5: // p2 ddr
			send_port(space, 2, m_ports[2] & data);
			m_ddrs[2] = data;
			break;

		case 8: // p3
			send_port(space, 3, data & m_ddrs[3]);
			m_ports[3] = data;
			break;

		case 9: // p3 ddr
			send_port(space, 3, m_ports[3] & data);
			m_ddrs[3] = data;
			break;
	}
}

READ8_MEMBER(m5074x_device::tmrirq_r)
{
	switch (offset)
	{
		case 0:
			return m_tmr12pre;

		case 1:
			return m_tmr1;

		case 2:
			return m_tmr2;

		case 3:
			return m_tmrxpre;

		case 4:
			return m_tmrx;

		case 5:
			return m_intctrl;

		case 6:
			return m_tmrctrl;
	}

	return 0xff;
}

WRITE8_MEMBER(m5074x_device::tmrirq_w)
{
//  printf("%02x to tmrirq @ %d\n", data, offset);

	switch (offset)
	{
		case 0:
			m_tmr12pre = data;
			recalc_timer(0);
			recalc_timer(1);
			break;

		case 1:
			m_tmr1 = m_tmr1latch = data;
			break;

		case 2:
			m_tmr2 = m_tmr2latch = data;
			break;

		case 3:
			m_tmrxpre = m_tmrxlatch = data;
			recalc_timer(2);
			break;

		case 4:
			m_tmrx = data;
			break;

		case 5:
			m_intctrl = data;
			recalc_irqs();
			break;

		case 6:
			m_tmrctrl = data;
			recalc_irqs();
			break;
	}
}

/* M50740 - baseline for this familiy */
static ADDRESS_MAP_START( m50740_map, AS_PROGRAM, 8, m50740_device )
	AM_RANGE(0x0000, 0x005f) AM_RAM
	AM_RANGE(0x00e0, 0x00e9) AM_READWRITE(ports_r, ports_w)
	AM_RANGE(0x00f9, 0x00ff) AM_READWRITE(tmrirq_r, tmrirq_w)
	AM_RANGE(0x1400, 0x1fff) AM_ROM AM_REGION(M5074X_INTERNAL_ROM_REGION, 0)
ADDRESS_MAP_END

m50740_device::m50740_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock) :
	m5074x_device(mconfig, M50740, "Mitsubishi M50740", tag, owner, clock, ADDRESS_MAP_NAME(m50740_map), "m50740", __FILE__)
{
}

m50740_device::m50740_device(const machine_config &mconfig, device_type type, const char *name, const char *tag, device_t *owner, UINT32 clock, const char *shortname, const char *source) :
	m5074x_device(mconfig, type, name, tag, owner, clock, ADDRESS_MAP_NAME(m50740_map), shortname, source)
{
}

/* M50741 - 50740 with a larger internal ROM */
static ADDRESS_MAP_START( m50741_map, AS_PROGRAM, 8, m50741_device )
	AM_RANGE(0x0000, 0x005f) AM_RAM
	AM_RANGE(0x00e0, 0x00e9) AM_READWRITE(ports_r, ports_w)
	AM_RANGE(0x00f9, 0x00ff) AM_READWRITE(tmrirq_r, tmrirq_w)
	AM_RANGE(0x1000, 0x1fff) AM_ROM AM_REGION("internal", 0)
ADDRESS_MAP_END

m50741_device::m50741_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock) :
	m5074x_device(mconfig, M50740, "Mitsubishi M50741", tag, owner, clock, ADDRESS_MAP_NAME(m50741_map), "m50741", __FILE__)
{
}

m50741_device::m50741_device(const machine_config &mconfig, device_type type, const char *name, const char *tag, device_t *owner, UINT32 clock, const char *shortname, const char *source) :
	m5074x_device(mconfig, type, name, tag, owner, clock, ADDRESS_MAP_NAME(m50741_map), shortname, source)
{
}