Tri-state Buffers and Multiplexers
By adding text inside Logisim, we can create circuit files that walk the user through different examples.
The figure below shows the tristate_mux.circ
file that
presents the topics of tristate buffers,
“floating” values (the wire is not driven),
“error” values (the wire is being driven to opposite values),
and implementing multiplexers
with tristate buffers or combinational gates.
The circuit file mux4.circ
shows the difference
for a multiplexer selecting from four inputs (4-to-1 multiplexer):