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// license:BSD-3-Clause
// copyright-holders:Nigel Barnes
/**********************************************************************

    Vine Micros Romboard '3' (Master OS Overlay Board)

    http://chrisacorns.computinghistory.org.uk/8bit_Upgrades/Vine_MasterOSoverlay.html

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


#ifndef MAME_BUS_BBC_INTERNAL_OVERLAY_H
#define MAME_BUS_BBC_INTERNAL_OVERLAY_H

#include "internal.h"


//**************************************************************************
//  TYPE DEFINITIONS
//**************************************************************************

class bbc_overlay_device :
	public device_t,
	public device_bbc_internal_interface
{
public:
	// construction/destruction
	bbc_overlay_device(const machine_config &mconfig, const char *tag, device_t *owner, const XTAL &clock);

protected:
	// device-level overrides
	virtual void device_start() override;

	// optional information overrides
	virtual void device_add_mconfig(machine_config &config) override;
	virtual ioport_constructor device_input_ports() const override;

	virtual bool overrides_rom() override { return true; }
	virtual bool overrides_mos() override { return true; }
	virtual void romsel_w(offs_t offset, uint8_t data) override { m_romsel = data & 0x0f; }
	virtual uint8_t paged_r(offs_t offset) override;
	virtual void paged_w(offs_t offset, uint8_t data) override;
	virtual uint8_t mos_r(offs_t offset) override;

private:
	required_device_array<bbc_romslot_device, 3> m_rom;
	required_ioport_array<3> m_link_rom;

	uint8_t m_romsel;
};


// device type definition
DECLARE_DEVICE_TYPE(BBC_OVERLAY, bbc_overlay_device);


#endif /* MAME_BUS_BBC_INTERNAL_OVERLAY_H */