void star_state::tstar540_map(address_map &map)
{
	sstar28k_map(map);

	map(0x4000, 0x5fff).rom();
	map(0x8000, 0x9fff).rom();
}

void star_state::tstar540(machine_config &config)
{
	sstar28k(config);

	/* basic machine hardware */
	R65C02(config.replace(), m_maincpu, 5530000);
	m_maincpu->set_addrmap(AS_PROGRAM, &star_state::tstar540_map);

	const attotime irq_period = attotime::from_hz(5530000 / 0x4000); // 4020 Q14
	m_maincpu->set_periodic_int(FUNC(star_state::nmi_line_pulse), irq_period);

	config.set_default_layout(layout_saitek_tstar432);
}


ROM_START( tstar540 )
	ROM_REGION( 0x10000, "maincpu", 0 )
	ROM_LOAD("kso", 0x4000, 0x2000, CRC(x) SHA1(x) )
	ROM_LOAD("yo1d-j.u4", 0x8000, 0x8000, CRC(aa993096) SHA1(06db69a284eaf022b26e1087e09d8d459d270d03) )
ROM_END