void fastinvaders_state::fastinvaders_8275(machine_config &config) { fastinvaders(config); m_maincpu->set_addrmap(AS_IO, &fastinvaders_state::fastinvaders_8275_io); I8275(config, m_crtc8275, 10000000); /* guess */ // does not configure a very useful resolution(!) m_crtc8275->set_character_width(16); // m_crtc8275->set_display_callback(FUNC(apogee_state::display_pixels)); // m_crtc8275->drq_wr_callback().set("dma8257", FUNC(i8257_device::dreq2_w)); }