Hi folks, I was wondering if anyone can help me. I am doing a media design course and i have my exam next week. However our multimedia fundamentals tutor left a few months ago and we have only had an unqualified stand in teacher. Anyway i found out just recently that a few things which appear in the exam we have not been taught. I was wondering if anyone can help me work out this boolean expression. I am unable to get the right answer. I know that the diagrams represent AND and NOT. But i am unable to work it out as it confuses me as more then one thing is going on. I have tried searching online but to no avail as they are either too simple or far too complicated. Thanks
We're not going to do your homework for you, but it's very simple to do this kind of problem. You have the gates NOT, OR and AND. The logic tables are: NOT: Code: INPUT | OUTPUT 0 | 1 1 | 0 AND: Code: INPUT | OUTPUT A B | 0 0 | 0 0 1 | 0 1 0 | 0 1 1 | 1 OR: Code: INPUT | OUTPUT A B | 0 0 | 0 0 1 | 1 1 0 | 1 1 1 | 1 To do the first line you should do it as follows: Input A = 0 Input B = 0 Input C = 0 NOT input A (0) = 1 Now we know that one of the inputs for the OR gate is 1. Then we AND inputs B and C. Looking at the truth table, B (0) and C (0) result in 0. Therefore the input for the OR gate is 1 (NOT A) and 0 (AND 0 and 0) Therefore the output of the OR gate is the result of OR 1 and 0. Which is 1. Therefore your first answer in the table is 1! HTH
+rep for RTT for giving a professional answer to a question that shouldn't be here anyway. Well done john
omg thats the basics of boolean.. yeah agree with RTT- least know what the symbols mean- that's about as easy as it gets.. look at it like this, might be easier to see it like this.. IF (A = 0) OR (B AND C = 1) THEN X=1 there's de morgans laws too, commutative, associative, distributive law too- probably have to learn these afterwards
basics of boolean which any designer should know as its LOGIC gates. sorry buddy lets face it, do your own homework.
hehe I wrote a midterm on boolean for my class at college.. it's not even used out in the field- if you program plc's, this is the logic you'll follow though.. whatever kingred XD I'm a programmer at heart- I think boolean algebra is a waste of time cause wiring diagrams are'nt written like this out in the field- long as you understand what the symbols mean you can do these types of problems- really just academic exercise.. I was just pointing out how simple this logic is if you take like 5 minutes to look up the symbols anyways
Wrong, boolean algebra isnt a waste of time at all. It allows the design and synthesis of nearly any digital system, requiring logic, to be built in its simplest form. Saving on silicon area and granting reduction in complexity meaning the circuit is easier to debug. Lets face it why use 10 gates when the boolean expression shows us we only need 4? Anyways, heres the answer:
well the work I've done in rslogix for allen bradley plc's is basically the same thing.. electrical it's all standard wiring diagrams if your a maintenance mech.. you just don't run across boolean algebra outside the classroom when working on industrial equipment and chrome you gave him all the answers- was with RTT on this one.. he needs to do it himself.. ah nm.. shouldn't have posted in here, it's obvious you guys know WAY more than I do! *sarcasm
How very astute of you. If you want to debate the moral implications of having someone do your homework for you, then do it on your own time. Starla, asked a question and I answered it, simple as that. Now yeah, it would be beneficial for him/her to do it on their own, but if they want to hurt themselves thats their choice!
Besides the distance between RTT giving a clue and Chrome answering was large enough to let him try it.
Thanks RTT, the way you had written it out i managed to understand it better. I knew what NOT, AND, OR stands for and was only shown very basic tables in college. However Maths and technical stuff has never been my strong point so perhaps some of you may find all this easy but other students in my class were also confused of the boolean expressions as we had not seen one before. Thanks chromex for your help Actually i already had the answers as the past paper i was given contains the answers. I asked for help as i was unable to work out how the answers came about from the pic. I now know where i was going wrong and the penny has finally dropped. Oh and i am female btw.
The easiest way to do these when you're new to them is to just write the input values all over the paper (in pencil ) and just work through for each input and gate, one at a time, referencing the truth tables when you need to. It's 100x easier that way. You can even give each input a label as well as the gates.
Agreed - I scrawl the inputs (or outputs) of each subsequent gate from beginning to end to find out the sequence.
Or use a Karnaugh map, that was always my favourite method for dealing with Boolean algebra. Moriquendi
I remembered this from college 30 yrs. ago. Must be pretty useful somewhere in the real world. Must not be in Colorado though. I wonder what other arcane arts I was taught in college that are still around? Punch cards? Paper tape. JCL? john
