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SamD, Mark this. :) (1 Viewer)

-X-

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SamD, can u Mark this please? :)

lol, i want a teachers comment on this. What would you give me out of 6 for this:

"Construct a logic circuit for the operation of the lights".

http://www.blizzardhacks.net/upload/images3/TrainLightsQuestion.1067697157.jpg

My answer is here:
http://www.blizzardhacks.net/upload/images3/TrainLights.1067695913.jpg


What will that get me out of 6? I know theires is a simple mistake in there though (wondering if the answer is detailed enough?).


THANKS ALLOT!!! :D:)

Edit: Arrg...sorry, the title sounds rude and i cant change it! While typing, i didn't notice or realise what i was saying until i re-read it. Sounds stupid and looks rude to me.

Sorry again....
 
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SamD

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You're answer is a circuit diagram not a truth table. So you get 0/6.

If the question had asked for a circuit diagram then its a much more difficult one. If so then your answer is really good, the green part is correct, the red part is also correct. However your amber light can be on at the same time as the red light. (You probably would get 4/6, which is a great mark for such a tough question).

You need some gates to turn off the amber light whenever the red light is on. Probably the reverse is easier to implement. ie. when the red is off (not red) AND one of the amber sensors is on then turn the amber light on. Logically I think this is
(NOT(S1 OR S3)) AND (S1 OR S4).

I'll scan my sketch, and you can check it....
 

-X-

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Sorry it was 3am, the question was design a circuit not a truth table. Yes that was the mistake SamD mentioned that i i was talking about (not turning off when red was off etc...). I couldn't figure it out. I'll have a look at yours. Thanks.


edit: hmm yes. I really need to start thinking about NOR gates too while im constructing circuits, hardly ever use them. Thanks :)
 
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Ragerunner

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Ahhh....So glad I picked evolution of programming languages. It's all about regurgitating answers :)
 

-X-

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Originally posted by Ragerunner
Ahhh....So glad I picked evolution of programming languages. It's all about regurgitating answers :)
lol yeh but if you enjoy electronics then you'll love this topic.
 

-X-

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SamD, would knowing boolean algebra help in designing circuits like these?
 

Winston

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Originally posted by -X-
SamD, would knowing boolean algebra help in designing circuits like these?
I wonder that too!!, but it's an extension topic in his text book and damn hard to understand.
 

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