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Diffstat (limited to 'src/lib/netlist/devices/nld_82S126.cpp')
-rw-r--r--src/lib/netlist/devices/nld_82S126.cpp85
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