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truth table to boolean expression or schematics Answered

need help converting the truth table to boolean expression or even better, schematics

1. i don't know electronics too much
2. i am not a student nor is this an assignment

simply looking for help in converting this truth table

Discussions

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Kiteman

8 years ago

If this is a genuine challenge to the creativity of the membership, it should really be a forum topic.

However, I suspect this may be a school-set challenge?


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steveastroukKiteman

Answer 8 years ago

The challenge looks like a school test, the components don't though. No current limiting resistors, no logic .

Odd

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Re-designsteveastrouk

Answer 8 years ago

I don't have the patience to do this kind of stuff anymore.  I would just write a basic program to decipher it and be done with it.  But I'm sure there is a way to do this using just parts and no programs.

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orksecurityRe-design

Answer 8 years ago

There is, of course. Not very hard to make it work. Somewhat harder to minimize it.

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steveastroukorksecurity

Answer 8 years ago

I know we were taught a lot about minimisation techniques - I wonder if modern students are ? Or if its even worth it anymore.

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Re-designsteveastrouk

Answer 8 years ago

Looking at the way software is written, I don't think that programming students are taught about minimization.  Give them 64K of memory to use and they would burn that just writing their copyright info! (with a few exceptions)

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32teethRe-design

Answer 8 years ago

okay, you seem to have gone off topic here
the help i am looking for, this is NOT school related nor it is how minified, abstract, of obfuscated your code is

turn the above truth table into a circuit board - NO CHIPS

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Re-design32teeth

Answer 8 years ago

Some of the logic states are very simple to implement.  I won't bore you describing them.

But several of the states you define are going to be difficult if not impossible to do with out using logic gates.  They are very simple to use.  They have been designed of off the shelf use as ic's.  But not allowing their use makes what may seem very simple to you a very complicated project.

You can find a description of the gates you need here.

You can find circuit descriptions for building logic gates out of transistors and such here.  This one also contains more info on how they work.  Check out the signal gate.  That on looks really interesting to me.

Now if you've got a free Sunday afternoon then you won't have any problem trying to "turn the above truth table into a circuit board - NO CHIPS".

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orksecuritysteveastrouk

Answer 8 years ago

"any wiring, diodes, resistors, logic gates required"

Definitely looks like homework. Simple logic with ands/ors/nots can easily do this.  Think about what the logic has to be for one set of r/g/b LEDs, then replicate it for the others.

The real trick is doing it with maximal efficiency; you can probably combine some of the sub-expressions and/or reduce the number of parts by using gates that have negation built into them or more complicated gates. Or do some passive logic using diodes or open-collector gates. But... "Make it work, make it good, make it great, in that order" until you know the shortcuts.

The trivial but expensive solution, since it did say "any", is to burn that truth table into a PROM.

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steveastrouk

8 years ago

Not enough components. You at least need some simple logic

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steveastrouk32teeth

Answer 8 years ago

You have a truth table, which seems to contain all you need. Do you know how to minimise the logic by  writing a Karnaugh map ? 

Steve

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32teethsteveastrouk

Answer 8 years ago

i added the caviate for additional parts and a truth table