// license:BSD-3-Clause // copyright-holders:smf #include "emu.h" #include "clock.h" const device_type CLOCK = device_creator; clock_device::clock_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock) : device_t(mconfig, CLOCK, "Clock", tag, owner, clock, "clock", __FILE__), m_signal(0), m_timer(nullptr), m_signal_handler(*this) { } void clock_device::device_start() { m_signal_handler.resolve(); save_item(NAME(m_signal)); } void clock_device::device_clock_changed() { update_timer(); } attotime clock_device::period() { if (m_clock > 0) return attotime::from_hz(m_clock * 2); return attotime::never; } void clock_device::device_timer(emu_timer &timer, device_timer_id id, int param, void *ptr) { m_signal = !m_signal; m_signal_handler(m_signal); m_timer->adjust(period()); } void clock_device::update_timer() { if (!m_signal_handler.isnull() && m_clock > 0) { if (m_timer == nullptr) { m_timer = timer_alloc(0); m_timer->adjust(period()); } else { attotime next = period() - m_timer->elapsed(); if (next < attotime::zero) { next = attotime::zero; } m_timer->adjust(next); } } else if (m_timer != nullptr) { m_timer->adjust(attotime::never); } }