// license:BSD-3-Clause // copyright-holders:Miodrag Milanovic /*************************************************************************** Generic 8bit and 16 bit latch devices ***************************************************************************/ #include "emu.h" #include "gen_latch.h" //************************************************************************** // DEVICE TYPE DEFINITIONS //************************************************************************** const device_type GENERIC_LATCH_8 = device_creator; const device_type GENERIC_LATCH_16 = device_creator; //************************************************************************** // TEMPALTE INSTANTIATIONS //************************************************************************** template class device_finder; template class device_finder; template class device_finder; template class device_finder; //************************************************************************** // LIVE DEVICE //************************************************************************** //------------------------------------------------- // generic_latch_base_device - constructor //------------------------------------------------- generic_latch_base_device::generic_latch_base_device(const machine_config &mconfig, device_type type, const char *name, const char *tag, device_t *owner, u32 clock, const char *shortname, const char *source) : device_t(mconfig, type, name, tag, owner, clock, shortname, source), m_latch_written(false), m_data_pending_cb(*this) { } //------------------------------------------------- // device_start - device-specific startup //------------------------------------------------- void generic_latch_base_device::device_start() { m_data_pending_cb.resolve_safe(); save_item(NAME(m_latch_written)); } //------------------------------------------------- // device_reset - device-specific reset //------------------------------------------------- void generic_latch_base_device::device_reset() { m_latch_written = false; } //------------------------------------------------- // pending_r - tell whether the latch is waiting // to be read //------------------------------------------------- READ_LINE_MEMBER(generic_latch_base_device::pending_r) { return m_latch_written ? 1 : 0; } //------------------------------------------------- // set_latch_written - helper to signal that latch // has been written or has been read //------------------------------------------------- void generic_latch_base_device::set_latch_written(bool latch_written) { if (m_latch_written != latch_written) { m_latch_written = latch_written; m_data_pending_cb(latch_written ? 1 : 0); } } //------------------------------------------------- // generic_latch_8_device - constructor //------------------------------------------------- generic_latch_8_device::generic_latch_8_device(const machine_config &mconfig, const char *tag, device_t *owner, u32 clock) : generic_latch_base_device(mconfig, GENERIC_LATCH_8, "Generic 8-bit latch", tag, owner, clock, "generic_latch_8", __FILE__), m_latched_value(0) { } READ8_MEMBER( generic_latch_8_device::read ) { set_latch_written(false); return m_latched_value; } WRITE8_MEMBER( generic_latch_8_device::write ) { machine().scheduler().synchronize(timer_expired_delegate(FUNC(generic_latch_8_device::sync_callback), this), data); } WRITE8_MEMBER( generic_latch_8_device::preset_w ) { m_latched_value = 0xff; } WRITE8_MEMBER( generic_latch_8_device::clear_w ) { m_latched_value = 0x00; } WRITE_LINE_MEMBER( generic_latch_8_device::preset_w ) { m_latched_value = 0xff; } WRITE_LINE_MEMBER( generic_latch_8_device::clear_w ) { m_latched_value = 0x00; } //------------------------------------------------- // soundlatch_sync_callback - time-delayed // callback to set a latch value //------------------------------------------------- void generic_latch_8_device::sync_callback(void *ptr, s32 param) { u8 value = param; // if the latch has been written and the value is changed, log a warning if (is_latch_written() && m_latched_value != value) logerror("Warning: latch written before being read. Previous: %02x, new: %02x\n", m_latched_value, value); // store the new value and mark it not read m_latched_value = value; set_latch_written(true); } //------------------------------------------------- // device_start - device-specific startup //------------------------------------------------- void generic_latch_8_device::device_start() { // register for state saving generic_latch_base_device::device_start(); save_item(NAME(m_latched_value)); } //------------------------------------------------- // generic_latch_16_device - constructor //------------------------------------------------- generic_latch_16_device::generic_latch_16_device(const machine_config &mconfig, const char *tag, device_t *owner, u32 clock) : generic_latch_base_device(mconfig, GENERIC_LATCH_16, "Generic 16-bit latch", tag, owner, clock, "generic_latch_16", __FILE__), m_latched_value(0) { } READ16_MEMBER( generic_latch_16_device::read ) { set_latch_written(false); return m_latched_value; } WRITE16_MEMBER( generic_latch_16_device::write ) { machine().scheduler().synchronize(timer_expired_delegate(FUNC(generic_latch_16_device::sync_callback), this), data); } WRITE16_MEMBER( generic_latch_16_device::preset_w ) { m_latched_value = 0xffff; } WRITE16_MEMBER( generic_latch_16_device::clear_w ) { m_latched_value = 0x0000; } WRITE_LINE_MEMBER( generic_latch_16_device::preset_w ) { m_latched_value = 0xffff; } WRITE_LINE_MEMBER( generic_latch_16_device::clear_w ) { m_latched_value = 0x0000; } //------------------------------------------------- // soundlatch_sync_callback - time-delayed // callback to set a latch value //------------------------------------------------- void generic_latch_16_device::sync_callback(void *ptr, s32 param) { u16 value = param; // if the latch has been written and the value is changed, log a warning if (is_latch_written() && m_latched_value != value) logerror("Warning: latch written before being read. Previous: %02x, new: %02x\n", m_latched_value, value); // store the new value and mark it not read m_latched_value = value; set_latch_written(true); } //------------------------------------------------- // device_start - device-specific startup //------------------------------------------------- void generic_latch_16_device::device_start() { // register for state saving generic_latch_base_device::device_start(); save_item(NAME(m_latched_value)); }