diff options
Diffstat (limited to 'src/lib/netlist/devices/nld_roms.cpp')
-rw-r--r-- | src/lib/netlist/devices/nld_roms.cpp | 68 |
1 files changed, 68 insertions, 0 deletions
diff --git a/src/lib/netlist/devices/nld_roms.cpp b/src/lib/netlist/devices/nld_roms.cpp index de440b4a8d2..a0bee0b60cd 100644 --- a/src/lib/netlist/devices/nld_roms.cpp +++ b/src/lib/netlist/devices/nld_roms.cpp @@ -96,6 +96,72 @@ namespace netlist nld_power_pins m_power_pins; }; + NETLIB_OBJECT(mcm14524_rom) + { + NETLIB_CONSTRUCTOR_MODEL(mcm14524_rom, "CD4XXX") + , m_enabled(*this, "m_enabled", true) + , m_latched_rom(*this, "m_latched_rom", 0) + , m_A(*this, 1, "A{}", NETLIB_DELEGATE(addr)) + , m_CLK(*this, "CLK", NETLIB_DELEGATE(addr)) + , m_clk_old(*this, "m_clk_old", true) + , m_EN(*this, "EN", NETLIB_DELEGATE(en)) + , m_B(*this, 1, "B{}", 0) + , m_ROM(*this, "ROM") + , m_taccc(*this, "m_taccc", netlist_time::from_nsec(1350)) + , m_taccen(*this, "m_taccen", netlist_time::from_nsec(245)) + , m_power_pins(*this, NETLIB_DELEGATE(vdd_vss)) + { + } + + private: + inline NETLIB_HANDLERI(en) + { + m_enabled = m_EN(); + uint8_t o = m_enabled ? m_latched_rom : 0; // outputs are forced to 0 by enable going low; this chip does not have tri-state outputs! + for (std::size_t i=0; i<4; i++) + { + m_B[i].push((o >> i) & 1, m_taccen); + } + } + + inline NETLIB_HANDLERI(addr) + { + if (!m_CLK() && m_clk_old) // latch on falling edge + { + const auto addr = m_A(); + m_latched_rom = m_ROM[addr]; + } + m_clk_old = m_CLK(); + uint8_t o = m_enabled ? m_latched_rom : 0; // outputs are forced to 0 by enable going low; this chip does not have tri-state outputs! + for (std::size_t i=0; i<4; i++) + { + m_B[i].push((o >> i) & 1, m_taccc); + } + } + + inline NETLIB_HANDLERI(vdd_vss) + { + auto d = m_power_pins.VCC()() - m_power_pins.GND()(); + if (d > 0.1) // avoid unrealistic values + { + m_taccc = netlist_time::from_nsec(gsl::narrow_cast<unsigned>(7615.5 / d - 181)); + m_taccen = netlist_time::from_nsec(gsl::narrow_cast<unsigned>(1292.5 / d - 14.6)); + } + } + + state_var<bool> m_enabled; + state_var<uint8_t> m_latched_rom; + object_array_t<logic_input_t, 8> m_A; + logic_input_t m_CLK; + state_var<bool> m_clk_old; + logic_input_t m_EN; + object_array_t<tristate_output_t, 4> m_B; + param_rom_t<uint8_t, 8, 4> m_ROM; + state_var<netlist_time> m_taccc; // propagation time for data vs CLK + state_var<netlist_time> m_taccen; // propagation time for data vs /EN + nld_power_pins m_power_pins; + }; + template <typename D> NETLIB_OBJECT(generic_prom) { @@ -230,12 +296,14 @@ namespace netlist using NETLIB_NAME(74S287) = NETLIB_NAME(generic_prom)<desc_74S287>; // 1024 bits, 32x32, used as 256x4 using NETLIB_NAME(2716) = NETLIB_NAME(generic_prom)<desc_2716>; // CE2Q = OE, CE1Q = CE using NETLIB_NAME(MK28000) = NETLIB_NAME(mk28000_prom); // 16384 bits, either 2048x8 or 4096x4, determined by OE1/OE2 use + using NETLIB_NAME(MCM14524) = NETLIB_NAME(mcm14524_rom); // 1024 bits, 256x4, latched address NETLIB_DEVICE_IMPL(82S126, "PROM_82S126", "+CE1Q,+CE2Q,+A0,+A1,+A2,+A3,+A4,+A5,+A6,+A7,@VCC,@GND") NETLIB_DEVICE_IMPL(74S287, "PROM_74S287", "+CE1Q,+CE2Q,+A0,+A1,+A2,+A3,+A4,+A5,+A6,+A7,@VCC,@GND") NETLIB_DEVICE_IMPL(82S123, "PROM_82S123", "+CEQ,+A0,+A1,+A2,+A3,+A4,@VCC,@GND") NETLIB_DEVICE_IMPL(2716, "EPROM_2716", "+CE2Q,+CE1Q,+A0,+A1,+A2,+A3,+A4,+A5,+A6,+A7,+A8,+A9,+A10,@VCC,@GND") NETLIB_DEVICE_IMPL(MK28000, "PROM_MK28000", "+OE1,+OE2,+ARQ,+A1,+A2,+A3,+A4,+A5,+A6,+A7,+A8,+A9,+A10,+A11,@VCC,@GND") + NETLIB_DEVICE_IMPL(MCM14524, "ROM_MCM14524", "+EN,+CLK,+A0,+A1,+A2,+A3,+A4,+A5,+A6,+A7,@VCC,@GND") } //namespace devices } // namespace netlist |