// license:BSD-3-Clause // copyright-holders:Fabio Priuli /********************************************************************** Nintendo Super Famicom & SNES SuperScope TODO: x,y positions are not correctly latched **********************************************************************/ #include "emu.h" #include "sscope.h" //************************************************************************** // DEVICE DEFINITIONS //************************************************************************** DEFINE_DEVICE_TYPE(SNES_SUPERSCOPE, snes_sscope_device, "snes_sscope", "Nintendo SNES / SFC SuperScope") static INPUT_PORTS_START( snes_sscope ) PORT_START("BUTTONS") PORT_BIT( 0x01, IP_ACTIVE_HIGH, IPT_BUTTON1 ) PORT_NAME("Superscope Fire") PORT_BIT( 0x02, IP_ACTIVE_HIGH, IPT_BUTTON2 ) PORT_NAME("Superscope Cursor") PORT_BIT( 0x04, IP_ACTIVE_HIGH, IPT_BUTTON3 ) PORT_NAME("Superscope Turbo") PORT_BIT( 0x08, IP_ACTIVE_HIGH, IPT_BUTTON4 ) PORT_NAME("Superscope Pause") PORT_BIT( 0x30, IP_ACTIVE_HIGH, IPT_UNUSED ) PORT_BIT( 0x40, IP_ACTIVE_HIGH, IPT_UNUSED ) // On-screen (handled below in port_poll) PORT_BIT( 0x80, IP_ACTIVE_HIGH, IPT_UNUSED ) // Noise PORT_START("SSX") PORT_BIT( 0xff, 0x80, IPT_LIGHTGUN_X ) PORT_NAME("Superscope X Axis") PORT_CROSSHAIR(X, 1.0, 0.0, 0) PORT_SENSITIVITY(25) PORT_KEYDELTA(15) PORT_START("SSY") PORT_BIT( 0xff, 0x80, IPT_LIGHTGUN_Y) PORT_NAME("Superscope Y Axis") PORT_CROSSHAIR(Y, 1.0, 0.0, 0) PORT_SENSITIVITY(25) PORT_KEYDELTA(15) INPUT_PORTS_END //------------------------------------------------- // input_ports - device-specific input ports //------------------------------------------------- ioport_constructor snes_sscope_device::device_input_ports() const { return INPUT_PORTS_NAME( snes_sscope ); } //************************************************************************** // LIVE DEVICE //************************************************************************** //------------------------------------------------- // snes_sscope_device - constructor //------------------------------------------------- snes_sscope_device::snes_sscope_device(const machine_config &mconfig, const char *tag, device_t *owner, const XTAL &clock) : device_t(mconfig, SNES_SUPERSCOPE, tag, owner, clock), device_snes_control_port_interface(mconfig, *this), m_buttons(*this, "BUTTONS"), m_xaxis(*this, "SSX"), m_yaxis(*this, "SSY"), m_strobe(0), m_idx(0), m_latch(0), m_x(0), m_y(0), m_turbo_lock(0), m_pause_lock(0), m_fire_lock(0) { } //------------------------------------------------- // device_start - device-specific startup //------------------------------------------------- void snes_sscope_device::device_start() { save_item(NAME(m_strobe)); save_item(NAME(m_idx)); save_item(NAME(m_latch)); save_item(NAME(m_x)); save_item(NAME(m_y)); save_item(NAME(m_turbo_lock)); save_item(NAME(m_pause_lock)); save_item(NAME(m_fire_lock)); } //------------------------------------------------- // device_reset - device-specific reset //------------------------------------------------- void snes_sscope_device::device_reset() { m_strobe = 0; m_idx = 0; m_latch = 0; m_x = 0; m_y = 0; m_turbo_lock = 0; m_pause_lock = 0; m_fire_lock = 0; } //------------------------------------------------- // poll //------------------------------------------------- void snes_sscope_device::port_poll() { // first read input bits uint8_t input = m_buttons->read(); m_x = m_xaxis->read(); m_y = m_yaxis->read(); m_idx = 0; // then start elaborating input bits // 1. only keep old turbo value m_latch &= 0x04; // 2. set onscreen/offscreen m_latch |= m_port->onscreen_cb(m_x, m_y) ? 0x00 : 0x40; // 3. pause is a button that is always edge sensitive if (BIT(input, 3) && !m_pause_lock) { m_latch |= 0x08; m_pause_lock = 1; } else if (!BIT(input, 3)) m_pause_lock = 0; // 4. turbo is a switch; toggle is edge sensitive if (BIT(input, 2) && !m_turbo_lock) { m_latch ^= 0x04; m_turbo_lock = 1; } else if (!BIT(input, 2)) m_turbo_lock = 0; // 5. cursor is a button that is always level sensitive m_latch |= BIT(input, 1); // 6. fire is a button with two behaviors: if turbo is active, trigger is level sensitive; // otherwise it is edge sensitive if (BIT(input, 0) && (BIT(m_latch, 2) || !m_fire_lock)) { m_latch |= 0x01; m_fire_lock = 1; } else if (!BIT(input, 0)) m_fire_lock = 0; // If we have pressed fire or cursor and we are on-screen and SuperScope is in Port2, then latch video signal. // Notice that this only works in Port2 because its IOBit pin is connected to bit7 of the IO Port, while Port1 // has IOBit pin connected to bit6 of the IO Port, and the latter is not detected by the H/V Counters. In other // words, you can connect SuperScope to Port1, but there is no way SNES could detect its on-screen position if ((m_latch & 0x03) && !(m_latch & 0x40)) m_port->gunlatch_cb(m_x, m_y); } //------------------------------------------------- // read //------------------------------------------------- uint8_t snes_sscope_device::read_pin4() { uint8_t res = 0; if (m_idx >= 8) // bits 8-15 = ID = all 1s; bits >= 16 all 1s res |= 0x01; else res |= BIT(m_latch, m_idx++); return res; } //------------------------------------------------- // write //------------------------------------------------- void snes_sscope_device::write_strobe(uint8_t data) { int old = m_strobe; m_strobe = data & 0x01; if (m_strobe < old) // 1 -> 0 transition port_poll(); }