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path: root/src/emu/bus/msx_cart/hfox.c
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#include "emu.h"
#include "hfox.h"


const device_type MSX_CART_HFOX = &device_creator<msx_cart_hfox>;


msx_cart_hfox::msx_cart_hfox(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
	: device_t(mconfig, MSX_CART_HFOX, "MSX Cartridge - Harry Fox", tag, owner, clock, "msx_cart_hfox", __FILE__)
	, msx_cart_interface(mconfig, *this)
{
	m_selected_bank[0] = m_selected_bank[1] = 0;
	m_bank_base[0] = m_bank_base[1] = NULL;
}


void msx_cart_hfox::device_start()
{
	save_item(NAME(m_selected_bank));

	machine().save().register_postload(save_prepost_delegate(FUNC(msx_cart_hfox::restore_banks), this));
}


void msx_cart_hfox::restore_banks()
{
	m_bank_base[0] = get_rom_base() + ((m_selected_bank[0] & 0x01) * 0x8000);
	m_bank_base[1] = get_rom_base() + ((m_selected_bank[1] & 0x01) * 0x8000) + 0x4000;
}


void msx_cart_hfox::device_reset()
{
	m_selected_bank[0] = m_selected_bank[1] = 0;
}


void msx_cart_hfox::initialize_cartridge()
{
	if (get_rom_size() < 0x10000)
	{
		fatalerror("rtype: Invalid ROM size\n");
	}

	restore_banks();
}


READ8_MEMBER(msx_cart_hfox::read_cart)
{
	if (offset >= 0x4000 && offset < 0xc000)
	{
		return m_bank_base[offset >> 15][offset & 0x3fff];
	}
	return 0xff;
}


WRITE8_MEMBER(msx_cart_hfox::write_cart)
{
	switch (offset)
	{
		case 0x6000:
			m_selected_bank[0] = data;
			restore_banks();
			break;

		case 0x7000:
			m_selected_bank[1] = data;
			restore_banks();
			break;

		default:
			printf("msx_cart_hfox: unhandled write %02x to %04x\n", data, offset);
			break;
	}
}