1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Drawing graphs of logic gates

  1. Mar 17, 2012 #1

    Femme_physics

    User Avatar
    Gold Member

    1. The problem statement, all variables and given/known data

    Graphs A and B are entries to a NOR gate with 2 inputs. Draw the output C.

    Graphs X and are entries to a XOR gate. Draw the output Z.

    2. Relevant equations

    abxy.jpg


    3. The attempt at a solution
    NOR.jpg


    XOR.jpg
     
  2. jcsd
  3. Mar 17, 2012 #2
    Looks good.
     
  4. Mar 17, 2012 #3

    I like Serena

    User Avatar
    Homework Helper

    I'm afraid you've slipped at ##\overline{x} \cdot y##.

    Tip: XOR means "either the one, or the other (but not both)".
     
  5. Mar 21, 2012 #4

    Femme_physics

    User Avatar
    Gold Member

    I'm confused...if XOR mean either this or that, how can u draw it on a single graph?

    EDIT: nevermind, I think I figured it out
     
    Last edited: Mar 21, 2012
  6. Mar 21, 2012 #5

    Femme_physics

    User Avatar
    Gold Member

    Last edited by a moderator: May 5, 2017
  7. Mar 21, 2012 #6

    NascentOxygen

    User Avatar

    Staff: Mentor

    You are making heavy work of this, Femme_physics. Would you like to start again?

    All you need are 3 graphs: x and y, and a blank one for your answer. https://www.physicsforums.com/images/icons/icon3.gif [Broken]

    Now graph the answer following this EXCLUSIVE-OR rule: where x differs from y, draw
    logic level 1. (And if x equals y, draw level 0.)

    That's all there is to it. Too easy! :smile:

    I'm not sure why your output trails off to the right at logic 1, where x and y are both at 0 https://www.physicsforums.com/images/icons/icon5.gif [Broken]
     
    Last edited by a moderator: May 5, 2017
  8. Mar 22, 2012 #7

    Femme_physics

    User Avatar
    Gold Member

    Oops, you're right, but I think this is my only mistake right?

    As far as "heavy work" -- well, I think it has an added value, being more thorough allows you to see the whole picture and revise the issue better.
     
  9. Mar 22, 2012 #8

    NascentOxygen

    User Avatar

    Staff: Mentor

    You have made another careless mistake, which will reveal itself.
    Exactly right, there is much to be gained by doing it the rigorous way, if only to confirm that the formula jives with the common sense approach. Unfortunately, the more steps you go through, the greater the opportunity to make mistakes. If this were an exam question, I'm sure the time allocation would be for the simple route. It is good to know how to do the task both ways.

    If you solve a problem two ways, agreement of answers usually confirms you as being correct. Disagreement can often highlight the error.
     
  10. Mar 22, 2012 #9

    Femme_physics

    User Avatar
    Gold Member

    Oh yes, I forgot to include that little block in the middle. Thank you :smile:

    Completely agree :approve:
     
  11. Mar 22, 2012 #10

    NascentOxygen

    User Avatar

    Staff: Mentor

    Congratulations on your 2000th post to physicsforums, Femme_physics! SUDsB.gif
     
  12. Mar 22, 2012 #11

    Femme_physics

    User Avatar
    Gold Member

    Last edited by a moderator: May 5, 2017
  13. Mar 22, 2012 #12

    NascentOxygen

    User Avatar

    Staff: Mentor

    Finally looks right. :wink:
     
  14. Mar 23, 2012 #13

    Femme_physics

    User Avatar
    Gold Member

    Thanks :)
     
  15. Apr 11, 2012 #14

    Femme_physics

    User Avatar
    Gold Member

    Last edited by a moderator: May 5, 2017
  16. Apr 11, 2012 #15

    NascentOxygen

    User Avatar

    Staff: Mentor

    Good idea. Don't forget exclusive-OR, too. :cool:
    yes​
     
    Last edited by a moderator: Apr 19, 2017
  17. Apr 13, 2012 #16

    Femme_physics

    User Avatar
    Gold Member

    Thanks NascentOx :)
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Drawing graphs of logic gates
  1. Drawing Logic Gates (Replies: 9)

  2. Logic Gates (Replies: 1)

  3. Logic Gates (Replies: 8)

  4. Logic Gates (Replies: 26)

Loading...