// license:BSD-3-Clause // copyright-holders:Ryan Holtz /* * nld_74166.cpp * * 74166: Parallel-Load 8-Bit Shift Register * * +--------------+ * SER |1 ++ 16| VCC * A |2 15| SH/LDQ * B |3 14| H * C |4 74166 13| QH * D |5 12| G * CLKINH |6 11| F * CLK |7 10| E * GND |8 9| CLRQ * +--------------+ * * SH/LDQ: Shift / !Load * CLKINH: Clock Inhibit * SER: Serial In * * Naming convention attempts to follow Texas Instruments datasheet * */ #include "nl_base.h" // FIXME: separate handlers for inputs namespace netlist::devices { NETLIB_OBJECT(74166) { NETLIB_CONSTRUCTOR(74166) , m_DATA(*this, { "H", "G", "F", "E", "D", "C", "B", "A" }, NETLIB_DELEGATE(inputs)) , m_SER(*this, "SER", NETLIB_DELEGATE(inputs)) , m_CLRQ(*this, "CLRQ", NETLIB_DELEGATE(inputs)) , m_SH_LDQ(*this, "SH_LDQ", NETLIB_DELEGATE(inputs)) , m_CLK(*this, "CLK", NETLIB_DELEGATE(inputs)) , m_CLKINH(*this, "CLKINH", NETLIB_DELEGATE(inputs)) , m_QH(*this, "QH") , m_shifter(*this, "m_shifter", 0) , m_last_CLRQ(*this, "m_last_CLRQ", 0) , m_last_CLK(*this, "m_last_CLK", 0) , m_power_pins(*this) { } private: NETLIB_RESETI() { m_shifter = 0; m_last_CLRQ = 0; m_last_CLK = 0; } NETLIB_HANDLERI(inputs) { netlist_sig_t old_qh = m_QH.net().Q(); netlist_sig_t qh = 0; netlist_time delay = NLTIME_FROM_NS(26); if (m_CLRQ()) { bool clear_unset = !m_last_CLRQ; if (clear_unset) { delay = NLTIME_FROM_NS(35); } if (!m_CLK() || m_CLKINH()) { qh = old_qh; } else if (!m_last_CLK) { if (!m_SH_LDQ()) { m_shifter = 0; for (std::size_t i=0; i<8; i++) m_shifter |= (m_DATA[i]() << i); } else { unsigned high_bit = m_SER() ? 0x80 : 0; m_shifter = high_bit | (m_shifter >> 1); } qh = m_shifter & 1; if (!qh && !clear_unset) { delay = NLTIME_FROM_NS(30); } } } m_last_CLRQ = m_CLRQ(); m_last_CLK = m_CLK(); m_QH.push(qh, delay); //FIXME } object_array_t m_DATA; logic_input_t m_SER; logic_input_t m_CLRQ; logic_input_t m_SH_LDQ; logic_input_t m_CLK; logic_input_t m_CLKINH; logic_output_t m_QH; state_var m_shifter; state_var m_last_CLRQ; state_var m_last_CLK; nld_power_pins m_power_pins; }; NETLIB_DEVICE_IMPL(74166, "TTL_74166", "+CLK,+CLKINH,+SH_LDQ,+SER,+A,+B,+C,+D,+E,+F,+G,+H,+CLRQ,@VCC,@GND") } // namespace netlist::devices