mame/src/mess/machine/vic1112.c

/**********************************************************************

    Commodore VIC-1112 IEEE-488 Interface Cartridge emulation

    Copyright MESS Team.
    Visit http://mamedev.org for licensing and usage restrictions.

**********************************************************************/

#include "vic1112.h"



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

#define M6522_0_TAG		"u4"
#define M6522_1_TAG		"u5"



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

const device_type VIC1112 = &device_creator<vic1112_device>;


//-------------------------------------------------
//  IEEE488_INTERFACE( ieee488_intf )
//-------------------------------------------------

static IEEE488_INTERFACE( ieee488_intf )
{
	DEVCB_NULL,
	DEVCB_NULL,
	DEVCB_NULL,
	DEVCB_NULL,
	DEVCB_NULL,
	DEVCB_DEVICE_LINE_MEMBER(M6522_1_TAG, via6522_device, write_cb1),
	DEVCB_NULL,
	DEVCB_NULL
};


//-------------------------------------------------
//  via6522_interface via0_intf
//-------------------------------------------------

WRITE_LINE_MEMBER( vic1112_device::via0_irq_w )
{
	m_via0_irq = state;

	m_slot->irq_w(m_via0_irq | m_via1_irq);
}

READ8_MEMBER( vic1112_device::via0_pb_r )
{
	/*

        bit     description

        PB0
        PB1
        PB2
        PB3     _EOI
        PB4     _DAV IN
        PB5     _NRFD IN
        PB6     _NDAC IN
        PB7     _ATN IN

    */

	UINT8 data = 0;

	data |= m_bus->eoi_r() << 3;
	data |= m_bus->dav_r() << 4;
	data |= m_bus->nrfd_r() << 5;
	data |= m_bus->ndac_r() << 6;
	data |= m_bus->atn_r() << 7;

	return data;
}

WRITE8_MEMBER( vic1112_device::via0_pb_w )
{
	/*

        bit     description

        PB0     _DAV OUT
        PB1     _NRFD OUT
        PB2     _NDAC OUT
        PB3
        PB4
        PB5
        PB6
        PB7

    */

	m_bus->dav_w(BIT(data, 0));
	m_bus->nrfd_w(BIT(data, 1));
	m_bus->ndac_w(BIT(data, 2));
}

static const via6522_interface via0_intf =
{
	DEVCB_NULL,
	DEVCB_DEVICE_MEMBER(DEVICE_SELF_OWNER, vic1112_device, via0_pb_r),
	DEVCB_NULL,
	DEVCB_NULL,
	DEVCB_NULL,
	DEVCB_NULL,

	DEVCB_NULL,
	DEVCB_DEVICE_MEMBER(DEVICE_SELF_OWNER, vic1112_device, via0_pb_w),
	DEVCB_NULL,
	DEVCB_NULL,
	DEVCB_NULL,
	DEVCB_NULL,

	DEVCB_DEVICE_LINE_MEMBER(DEVICE_SELF_OWNER, vic1112_device, via0_irq_w)
};


//-------------------------------------------------
//  via6522_interface via1_intf
//-------------------------------------------------

WRITE_LINE_MEMBER( vic1112_device::via1_irq_w )
{
	m_via1_irq = state;

	m_slot->irq_w(m_via0_irq | m_via1_irq);
}

static const via6522_interface via1_intf =
{
	DEVCB_NULL,
	DEVCB_DEVICE_MEMBER(IEEE488_TAG, ieee488_device, dio_r),
	DEVCB_NULL,
	DEVCB_DEVICE_LINE_MEMBER(IEEE488_TAG, ieee488_device, srq_r),
	DEVCB_NULL,
	DEVCB_NULL,

	DEVCB_DEVICE_MEMBER(IEEE488_TAG, ieee488_device, dio_w),
	DEVCB_NULL,
	DEVCB_NULL,
	DEVCB_NULL,
	DEVCB_DEVICE_LINE_MEMBER(IEEE488_TAG, ieee488_device, atn_w),
	DEVCB_DEVICE_LINE_MEMBER(IEEE488_TAG, ieee488_device, eoi_w),

	DEVCB_DEVICE_LINE_MEMBER(DEVICE_SELF_OWNER, vic1112_device, via1_irq_w)
};


//-------------------------------------------------
//  MACHINE_DRIVER( vic1112 )
//-------------------------------------------------

static MACHINE_CONFIG_FRAGMENT( vic1112 )
	MCFG_VIA6522_ADD(M6522_0_TAG, 0, via0_intf)
	MCFG_VIA6522_ADD(M6522_1_TAG, 0, via1_intf)

	MCFG_CBM_IEEE488_ADD(ieee488_intf, NULL)
MACHINE_CONFIG_END


//-------------------------------------------------
//  machine_config_additions - device-specific
//  machine configurations
//-------------------------------------------------

machine_config_constructor vic1112_device::device_mconfig_additions() const
{
	return MACHINE_CONFIG_NAME( vic1112 );
}



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

//-------------------------------------------------
//  vic1112_device - constructor
//-------------------------------------------------

vic1112_device::vic1112_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
    : device_t(mconfig, VIC1112, "VIC1112", tag, owner, clock),
	  device_vic20_expansion_card_interface(mconfig, *this),
	  m_via0(*this, M6522_0_TAG),
	  m_via1(*this, M6522_1_TAG),
	  m_bus(*this, IEEE488_TAG)
{
}


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

void vic1112_device::device_start()
{
	// state saving
	save_item(NAME(m_via0_irq));
	save_item(NAME(m_via1_irq));
}


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

void vic1112_device::device_reset()
{
	m_bus->ifc_w(0);
	m_bus->ifc_w(1);
}


//-------------------------------------------------
//  vic20_cd_r - cartridge data read
//-------------------------------------------------

UINT8 vic1112_device::vic20_cd_r(address_space &space, offs_t offset, UINT8 data, int ram1, int ram2, int ram3, int blk1, int blk2, int blk3, int blk5, int io2, int io3)
{
	if (!io2)
	{
		if (offset & 0x10)
		{
			data = m_via1->read(space, offset & 0x0f);
		}
		else
		{
			data = m_via0->read(space, offset & 0x0f);
		}
	}
	else if (!blk5)
	{
		if (offset & 0x1000)
		{
			data = m_blk5[offset & 0x17ff];
		}
	}

	return data;
}


//-------------------------------------------------
//  vic20_cd_w - cartridge data write
//-------------------------------------------------

void vic1112_device::vic20_cd_w(address_space &space, offs_t offset, UINT8 data, int ram1, int ram2, int ram3, int blk1, int blk2, int blk3, int blk5, int io2, int io3)
{
	if (!io2)
	{
		if (offset & 0x10)
		{
			m_via1->write(space, offset & 0x0f, data);
		}
		else
		{
			m_via0->write(space, offset & 0x0f, data);
		}
	}
}