diff options
Diffstat (limited to 'src/devices/bus/sms_ctrl/sports.cpp')
-rw-r--r-- | src/devices/bus/sms_ctrl/sports.cpp | 194 |
1 files changed, 194 insertions, 0 deletions
diff --git a/src/devices/bus/sms_ctrl/sports.cpp b/src/devices/bus/sms_ctrl/sports.cpp new file mode 100644 index 00000000000..4050159beb1 --- /dev/null +++ b/src/devices/bus/sms_ctrl/sports.cpp @@ -0,0 +1,194 @@ +// license:BSD-3-Clause +// copyright-holders:Fabio Priuli +/********************************************************************** + + Sega Master System "Sports Pad" (US model) emulation + +**********************************************************************/ + +// The games designed for the US model of the Sports Pad controller use the +// TH line of the controller port as output, to select which nibble, of the +// two axis bytes, will be read at a time. The Japanese cartridge Sports Pad +// Soccer uses a different mode, because the Sega Mark III lacks TH output, so +// there is a different Sports Pad model released in Japan (see sportsjp.c). + +// It was discovered that games designed for the Paddle Controller, released +// in Japan, switch to a mode incompatible with the original Paddle when +// detect the system region as Export. Similar to how the US model of the +// Sports Pad works, that mode uses the TH line as output to select which +// nibble of the X axis will be read. So, on an Export console version, paddle +// games are somewhat playable with the US Sport Pad model, though it needs to +// be used inverted and the trackball needs to be moved slowly, else the +// software for the paddle think it's moving backward. +// See http://mametesters.org/view.php?id=5872 for discussion. + +#include "sports.h" + + + +//************************************************************************** +// DEVICE DEFINITIONS +//************************************************************************** + +const device_type SMS_SPORTS_PAD = &device_creator<sms_sports_pad_device>; + +// time interval not verified +#define SPORTS_PAD_INTERVAL attotime::from_hz(XTAL_53_693175MHz/15/512) + + +void sms_sports_pad_device::device_timer(emu_timer &timer, device_timer_id id, int param, void *ptr) +{ + switch (id) + { + case TIMER_SPORTSPAD: + // values for x and y axis need to be resetted for Sports Pad games, but + // are not resetted for paddle games, so it was assumed the reset occurs + // only when this timer fires after the read state reached maximum value. + if (m_read_state == 3) + { + m_x_axis_reset_value = m_sports_x->read(); + m_y_axis_reset_value = m_sports_y->read(); + } + else + { + // set to maximum value, so it wraps to 0 at next increment + m_read_state = 3; + } + + break; + default: + assert_always(FALSE, "Unknown id in sms_sports_pad_device::device_timer"); + } +} + + +CUSTOM_INPUT_MEMBER( sms_sports_pad_device::th_pin_r ) +{ + return m_last_data; +} + + +INPUT_CHANGED_MEMBER( sms_sports_pad_device::th_pin_w ) +{ + m_read_state = (m_read_state + 1) & 3; + m_sportspad_timer->adjust(m_interval); + m_last_data = newval; +} + + +CUSTOM_INPUT_MEMBER( sms_sports_pad_device::dir_pins_r ) +{ + UINT8 data = 0; + + switch (m_read_state) + { + case 0: + data = (m_sports_x->read() - m_x_axis_reset_value) >> 4; + break; + case 1: + data = (m_sports_x->read() - m_x_axis_reset_value); + break; + case 2: + data = (m_sports_y->read() - m_y_axis_reset_value) >> 4; + break; + case 3: + data = (m_sports_y->read() - m_y_axis_reset_value); + break; + } + + // The returned value is inverted due to IP_ACTIVE_LOW mapping. + return ~(data & 0x0f); +} + + +static INPUT_PORTS_START( sms_sports_pad ) + PORT_START("SPORTS_IN") + PORT_BIT( 0x0f, IP_ACTIVE_LOW, IPT_SPECIAL ) PORT_CUSTOM_MEMBER(DEVICE_SELF, sms_sports_pad_device, dir_pins_r, NULL) // Directional pins + PORT_BIT( 0x10, IP_ACTIVE_LOW, IPT_UNUSED ) // Vcc + PORT_BIT( 0x20, IP_ACTIVE_LOW, IPT_BUTTON1 ) // TL (Button 1) + PORT_BIT( 0x40, IP_ACTIVE_LOW, IPT_SPECIAL ) PORT_CUSTOM_MEMBER(DEVICE_SELF, sms_sports_pad_device, th_pin_r, NULL) + PORT_BIT( 0x80, IP_ACTIVE_LOW, IPT_BUTTON2 ) // TR (Button 2) + + PORT_START("SPORTS_OUT") + PORT_BIT( 0x0f, IP_ACTIVE_LOW, IPT_UNUSED ) // Directional pins + PORT_BIT( 0x10, IP_ACTIVE_LOW, IPT_UNUSED ) // Vcc + PORT_BIT( 0x20, IP_ACTIVE_LOW, IPT_UNUSED ) // TL (Button 1) + PORT_BIT( 0x40, IP_ACTIVE_LOW, IPT_OUTPUT ) PORT_CHANGED_MEMBER(DEVICE_SELF, sms_sports_pad_device, th_pin_w, NULL) + PORT_BIT( 0x80, IP_ACTIVE_LOW, IPT_UNUSED ) // TR (Button 2) + + PORT_START("SPORTS_X") /* Sports Pad X axis */ + PORT_BIT( 0xff, 0x00, IPT_TRACKBALL_X ) PORT_SENSITIVITY(50) PORT_KEYDELTA(40) PORT_REVERSE + + PORT_START("SPORTS_Y") /* Sports Pad Y axis */ + PORT_BIT( 0xff, 0x00, IPT_TRACKBALL_Y ) PORT_SENSITIVITY(50) PORT_KEYDELTA(40) PORT_REVERSE +INPUT_PORTS_END + + +//------------------------------------------------- +// input_ports - device-specific input ports +//------------------------------------------------- + +ioport_constructor sms_sports_pad_device::device_input_ports() const +{ + return INPUT_PORTS_NAME( sms_sports_pad ); +} + + + +//************************************************************************** +// LIVE DEVICE +//************************************************************************** + +//------------------------------------------------- +// sms_sports_pad_device - constructor +//------------------------------------------------- + +sms_sports_pad_device::sms_sports_pad_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock) : + device_t(mconfig, SMS_SPORTS_PAD, "Sega SMS Sports Pad US", tag, owner, clock, "sms_sports_pad", __FILE__), + device_sms_control_port_interface(mconfig, *this), + m_sports_in(*this, "SPORTS_IN"), + m_sports_out(*this, "SPORTS_OUT"), + m_sports_x(*this, "SPORTS_X"), + m_sports_y(*this, "SPORTS_Y"), + m_read_state(0), + m_last_data(0), + m_x_axis_reset_value(0x80), // value 0x80 helps when start playing paddle games. + m_y_axis_reset_value(0x80), + m_interval(SPORTS_PAD_INTERVAL) +{ +} + + +//------------------------------------------------- +// device_start - device-specific startup +//------------------------------------------------- + +void sms_sports_pad_device::device_start() +{ + m_sportspad_timer = timer_alloc(TIMER_SPORTSPAD); + + save_item(NAME(m_read_state)); + save_item(NAME(m_last_data)); + save_item(NAME(m_x_axis_reset_value)); + save_item(NAME(m_y_axis_reset_value)); +} + + +//------------------------------------------------- +// sms_peripheral_r - sports pad read +//------------------------------------------------- + +UINT8 sms_sports_pad_device::peripheral_r() +{ + return m_sports_in->read(); +} + + +//------------------------------------------------- +// sms_peripheral_w - sports pad write +//------------------------------------------------- + +void sms_sports_pad_device::peripheral_w(UINT8 data) +{ + m_sports_out->write(data); +} |