diff options
Diffstat (limited to 'src/lib/netlist/devices/nld_82S126.cpp')
-rw-r--r-- | src/lib/netlist/devices/nld_82S126.cpp | 85 |
1 files changed, 85 insertions, 0 deletions
diff --git a/src/lib/netlist/devices/nld_82S126.cpp b/src/lib/netlist/devices/nld_82S126.cpp new file mode 100644 index 00000000000..d3a86ce84ee --- /dev/null +++ b/src/lib/netlist/devices/nld_82S126.cpp @@ -0,0 +1,85 @@ +// license:BSD-3-Clause +// copyright-holders:Ryan Holtz +/* + * nld_82S126.cpp + * + */ + +#include "nld_82S126.h" + +namespace netlist +{ + namespace devices + { + NETLIB_OBJECT(82S126) + { + NETLIB_CONSTRUCTOR(82S126) + , m_A(*this, {{"A0", "A1", "A2", "A3", "A4", "A5", "A6", "A7" }}) + , m_CE1Q(*this, "CE1Q") + , m_CE2Q(*this, "CE2Q") + , m_O(*this, {{"O1", "O2", "O3", "O4" }}) + , m_ROM(*this, "ROM") + { + } + + NETLIB_UPDATEI(); + + protected: + object_array_t<logic_input_t, 8> m_A; + logic_input_t m_CE1Q; + logic_input_t m_CE2Q; + object_array_t<logic_output_t, 4> m_O; + + param_rom_t<uint8_t, 8, 4> m_ROM; // 1024 bits, 32x32, used as 256x4 + }; + + NETLIB_OBJECT_DERIVED(82S126_dip, 82S126) + { + NETLIB_CONSTRUCTOR_DERIVED(82S126_dip, 82S126) + { + register_subalias("5", m_A[0]); + register_subalias("6", m_A[1]); + register_subalias("7", m_A[2]); + register_subalias("4", m_A[3]); + register_subalias("3", m_A[4]); + register_subalias("2", m_A[5]); + register_subalias("1", m_A[6]); + register_subalias("15", m_A[7]); + + register_subalias("13", m_CE1Q); + register_subalias("14", m_CE2Q); + + register_subalias("12", m_O[0]); + register_subalias("11", m_O[1]); + register_subalias("10", m_O[2]); + register_subalias("9", m_O[3]); + } + }; + + // FIXME: timing! + NETLIB_UPDATE(82S126) + { + unsigned o = 0xf; + + netlist_time delay = NLTIME_FROM_NS(25); + if (!m_CE1Q() && !m_CE2Q()) + { + unsigned a = 0; + for (std::size_t i=0; i<8; i++) + a |= (m_A[i]() << i); + + o = m_ROM[a]; + + delay = NLTIME_FROM_NS(50); + } + + // FIXME: Outputs are tristate. This needs to be properly implemented + for (std::size_t i=0; i<4; i++) + m_O[i].push((o >> i) & 1, delay); + } + + NETLIB_DEVICE_IMPL(82S126) + NETLIB_DEVICE_IMPL(82S126_dip) + + } //namespace devices +} // namespace netlist |