From the table, it shows the data selects equivalent number (0-7) will
connect to each pin at MUX and
DEMUX with same number pin. Each pin is the input from the system when
door is open which
connected to MUX.
At DEMUX,
the same pin number as MUX will be connected to give an active low output
which
controlled by the
counter.
From here, when
each door is open, the output from DEMUX will cause the system function
to alert
the security.
2. The pin 7 of 74LS151 MUX need
to be grounded because it only allow passing input signal to output
when it is
operated under active low condition.
3. Pin 3 is connected to +5V and
pin 2 to ground of 74LS138 DEMUX to enable G1 receive high input
and G2 a low
input for thr DEMUX to operate functionally.
4. a) Less wire needed for connection
b) Utilize
or maximize the bandwidth of wire.
c) Centralized
control, easier to check for error.
5.
6. a) Time Division Multiplexing
b) LAN connection.
c) Security
systems.