Finding a min gate input count realization of enabling logic ?

AI Thread Summary
The discussion revolves around finding a minimum gate input count realization for a home security system's enabling logic using AND and OR gates and inverters. The system includes six sensor inputs and a master switch that determines whether the alarm, lights, video cameras, and police call are activated based on detected intrusions. Participants suggest creating a comprehensive truth table for the 128 possible input combinations or focusing on specific outputs to simplify the process. Clarification on the meaning of inputs and how they drive outputs is emphasized as crucial for solving the problem. The urgency for a solution is expressed, highlighting the importance of assistance in this task.
mr_coffee
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Hello everyone, I'm confused on what they want me to do here:
it says:
Find a minimum gate input count realization of the enabling logic using AND and OR gates and inverters. Well This is my truth table i came up with, and the "enabler" is the M, the master switch( 0 secruit system on, 1 secuirty system off). Here is the picture: http://img145.imageshack.us/img145/6249/lastscan0oh.jpg any help would be great.
 
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You do not fully state what your problem is. Can it be assumed that there are seven imput variable lines (the six "S" lines, and the enable M)? If so, then there are 2^7, or 128 possible input line combinations. That makes for a long truth table, but it isn't difficult to work with. There are two basic approaches to working with this. 1) Either you can put everything into a 128 combination truth table, or 2) for each desired output line, you can eliminate all inputs that don't pertain to it, and then make four truth tables, one for each of those desired outputs.

First, though you need to specify clearly what the inputs mean, and from this what input combination drives each of the outputs.

KM
 
A home security system has a master switch that is used to enable an alarm,lights , video cameras and a call to local police in the event one or more of six sets of sensors detects an intrusion. the inputs, outputs and operation of the enabling logic are specified as follows:
inputs:
Si, i=0,1,2,3,4,5 - signals from six sensors sets(0-intrusion detected, 1 - no intrusion detected)
M-master switch(0 -security system on, 1-security system off)

outputs:
A-alarm (0-alarm on, 1 - alarm off)
L-lights(0-lights on ,1-lights off)
V-video cameras(0-video cameras off, 1-video cameras on)
C-call to police(0-call off,1-call on

Operation:

if one or more of the sets of sensros detects an intrusion and the security system is on , then all outputs are on. otherwise all outputs are off

find a minimum gate input count realization of the enabling logic using AND and OR gates and inverters.

------
PLZ HEEEEEEEEEEEEEEEEEEEEEEELP

it is so vital for me to find the solution urgently ,

any hints are welcome,,,,

TNXXXXXXXXX
 
A home security system has a master switch that is used to enable an alarm,lights , video cameras and a call to local police in the event one or more of six sets of sensors detects an intrusion. the inputs, outputs and operation of the enabling logic are specified as follows:
inputs:
Si, i=0,1,2,3,4,5 - signals from six sensors sets(0-intrusion detected, 1 - no intrusion detected)
M-master switch(0 -security system on, 1-security system off)

outputs:
A-alarm (0-alarm on, 1 - alarm off)
L-lights(0-lights on ,1-lights off)
V-video cameras(0-video cameras off, 1-video cameras on)
C-call to police(0-call off,1-call on

Operation:

if one or more of the sets of sensros detects an intrusion and the security system is on , then all outputs are on. otherwise all outputs are off

find a minimum gate input count realization of the enabling logic using AND and OR gates and inverters.

------
PLZ HEEEEEEEEEEEEEEEEEEEEEEELP

it is so vital for me to find the solution urgently ,

any hints are welcome,,,,

TNXXXXXXXXX[/QUOTE]
 
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