Help with a dice

Discussion in 'The Projects Forum' started by simo_x, Dec 28, 2010.

  1. simo_x

    Thread Starter Member

    Dec 23, 2010
    200
    6
    Hello, I am developing a little dice. It count from 1 to 6 but I have a problem.

    A zip with a bmp Image is attached with the post. I can't upload it as a photo due to high resolution. I am sorry.

    The problem is this: as it is when I turn on the circuit, the load counter is set to 1, but I need set it to 0 because I need to display 1 from the first moment.
    The automatic reload of the count is solved with an NAND gate when number 6 is in output from the synchronous counter, but I can't solve the first 1..


    I thought to use a transistor, but our teachers still don't have explained transistors and it don't mean that we can't use it.

    Hope you can help me.

    Thank you!
    Simon
     
    Last edited: Dec 28, 2010
  2. beenthere

    Retired Moderator

    Apr 20, 2004
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    You need to use pin 1 which will clear the counter to 0.
     
  3. simo_x

    Thread Starter Member

    Dec 23, 2010
    200
    6
    But I don't need to count from 0. From 1 to 6.
    Thank you.
     
    Last edited: Dec 28, 2010
  4. hgmjr

    Moderator

    Jan 28, 2005
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    Your explanation is somewhat fuzzy. In your initial statement you say you need to set it to 0 but in your reply to beenthere you say you do not need it to go to zero. Can you clarify this conflict?

    hgmjr
     
  5. simo_x

    Thread Starter Member

    Dec 23, 2010
    200
    6
    I was referring to the Load statement.
    The Load or Preset Enable (pin nº 9) is enabled with a logic 0. But I don't have to count from 0.
    Thank You.
     
    Last edited: Dec 28, 2010
  6. hgmjr

    Moderator

    Jan 28, 2005
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    C3 and R4 appear to be not connected to anything. Is that intentional?

    hgmjr
     
  7. simo_x

    Thread Starter Member

    Dec 23, 2010
    200
    6
    Well, this is something I forget to erase, I am sorry. Forget about C3 & R4.
     
  8. hgmjr

    Moderator

    Jan 28, 2005
    9,030
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    Consider them forgotten for now.

    hgmjr
     
  9. hgmjr

    Moderator

    Jan 28, 2005
    9,030
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    So what you are looking for is that when power is applied, the 7-segment display will display a constant "1". Then when you press the "switch", you want the count to start from 1.

    At the moment you are getting a zero when you power up.

    hgmjr
     
  10. bertus

    Administrator

    Apr 5, 2008
    15,648
    2,347
    Hello,

    There are two little mistakes in the schematic.
    I have drawn the the remarks into your schematic:

    [​IMG]

    Bertus
     
  11. simo_x

    Thread Starter Member

    Dec 23, 2010
    200
    6
    Thanks!

    Do you think the problem can be solved with a transistor or more than one? This counter should be perfect for do what I need, but the first 1 detail seems to be a little tricky..

    As the counter is synchronous I tried use a truth table in relationship between the counter outputs and the pin 9, implementing logic gates but it does not work..
     
  12. simo_x

    Thread Starter Member

    Dec 23, 2010
    200
    6
    Correct
    I Know, that is the real problem..
     
  13. hgmjr

    Moderator

    Jan 28, 2005
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    In addition to Bertus' comments, you also have Q3 output shorted to ground. It should be left disconnected in this application.

    hgmjr
     
  14. simo_x

    Thread Starter Member

    Dec 23, 2010
    200
    6
    I post a new correct image.. Sorry, i did not attacched with attention. :(
    I did not put resistors between 4511 and display because I still have to calculate the value. I left this problem as last.

    Thank you for your help.

    EDIT: I am working with Proteus, if you think it's better i attach the project..
     
    Last edited: Dec 28, 2010
  15. simo_x

    Thread Starter Member

    Dec 23, 2010
    200
    6
    However is not a problem with the counter. The counter will always start from 0 because when the power is supplied, the clock is not immediately connected to the counter. To do it I need to press the switch.. That's why I am thinking in a transistor or/and additional device.
     
  16. bertus

    Administrator

    Apr 5, 2008
    15,648
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    Hello,

    An other idea could be that the counter keeps running and the display driver is latching the numbers.

    Bertus
     
  17. hgmjr

    Moderator

    Jan 28, 2005
    9,030
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    I think bertus is on to something. You can connect the clock directly to the counter so that it is counting all the time. Then you can place an RC and the switch on the LM555 timer's reset line. That way when you press the switch the 555 will begin counting. When you let up the switch, the 555 will keep clocking until the cap discharges and shuts down the 555.

    hgmjr
     
  18. simo_x

    Thread Starter Member

    Dec 23, 2010
    200
    6
    The idea is not bad, the problem is the dice has to work as I thinked it.

    Take a look at the last change with 1 diode between the 555 and counter.
    When power is supplied, the number 0 appear just for a very short portion of second followed by a 1 (until the switch is pressed), because at that moment just one shot of clock is supplied.

    The AND gate and OR gate near the display are for the segment "a" for number 6. I like it on for show that number. :D

    Tell me what you think.. But off course, I believe in a better solution.


    Thanks
    Simon
     
    Last edited: Dec 28, 2010
  19. thatoneguy

    AAC Fanatic!

    Feb 19, 2009
    6,357
    718
    Dice is plural.

    If you have only one cube with sides numbered 1-6, it is referred to as a die.

    Carry on.
     
  20. Ron H

    AAC Fanatic!

    Apr 14, 2005
    7,050
    657
    The 4511 has a blanking input. How about decoding 0000 from your counter, and using that to blank the display?
     
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