Course Name: Digital Logic Design
Course Code: EEE 205
Time: 1 hour 20 minutes
SET-A
Marks
30
1. CO1/Cognitive/Create
Design a home security system that has a master switch, which is used to enable
an alarm, light, video cameras, and a call to local police in the event of one or
more of six sets of sensors detecting an intrusion. In addition, there are separate
switches to enable and disable the alarm, lights, and the call to local police. The
inputs, outputs, and operation of enabling logic are specified as follows:
Inputs:
Outputs:
A0: alarm (0 = alarm off, 1 = alarm on)
L0: light (0 = light off, 1 = light on)
P0: police call (0 = police call off, 1 = police call on)
V: video camera (0 = cameras off, 1 = cameras on)
Si, i=0,1, 2, 3, 4, 5: signals from six sensors sets (0 = no intrusion detected, 1
= intrusion detected)
M = master switch (0 = security system disabled, 1 = security system enabled)
A = alarm switch (0 = alarm disabled, 1 = alarm enabled)
L = light switch (0 = light disabled, 1 = light enabled)
P = police switch (0 = police call disabled, 1 = police call enabled)
Operations:
i) If only one sensor detects an intrusion and the security system (M)
as well as L are enabled, then L0 and V will be on, and all other
outputs will be off.
ii)
iii)
If two sensors detect intrusion and the security system (M) as well
as A, L are enabled, then A0, L0, and V will be on but P0 will be off.
If three or more sensors detect intrusion and the security system (M)
as well as A, L, P are enabled, then all the outputs will be on.
