Connect the two select inputs by wiring the s input

Connect the two select inputs by wiring the s input of the demultiplexer chip to the s input of the
multiplexer. Now,
the multiplexer and demultiplexer share the same select signal.
3. Next, connect the output of the multiplexer to the y input of the demultiplexer. The multiplexer
and demultiplexer should now be connected as shown in this diagram:
4. Verify that your mux-demux scheme works as expected by trying out different combinations of a,
b, and s.
Now connect the select inputs of the multiplexer and demultiplexer to a clock output by removing the “s”
input of the demultiplexer from the switch it is connected to and connecting it to the Magic Box’s clock
output.
TODO: Set both a and b to see what happens when your clock output is set to automatic ticking, and tick
frequency is set to 1 Hz. (Shown below) Then do this again with a clock output of 2 Hz, and again at 1
kHz. What do you notice?

To change frequency, Click Simulate, then Click Tick Frequency and select the frequency you want.
3 Multiplexing
TODO: Using Logisim, implement a circuit with three inputs: a, b, and s. This circuit should work as
follows: when s is off, the output is a AND b. When s is on, the output is a XOR b. As such, the s input
will be selecting which function to apply to a and b – do we AND or XOR? (Note: Multiplexers can be
found in the Plexers folder in Logisim, so please use it instead of constructing it from scratch. You do not