Newbie..need help with alarm clock

Discussion in 'The Projects Forum' started by Sugandh Sachdev, Oct 15, 2015.

  1. Sugandh Sachdev

    Thread Starter New Member

    Oct 15, 2015
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    I am a newbie with electronics and as a project I took alarm clock. I have made the digital clock using Binary counters and 7 segment display but I have no idea how to enable alarm system in it. Can you please at least give me an idea how it would be done or where to start from?
     
  2. Dodgydave

    Distinguished Member

    Jun 22, 2012
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    Lets start by you showing us the circuit that you have made, then we can assist you with it.
     
  3. Sugandh Sachdev

    Thread Starter New Member

    Oct 15, 2015
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  4. Dodgydave

    Distinguished Member

    Jun 22, 2012
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    I take the clock starts at Zero and goes upto 12-00-00, do you want to have an output at a certain time, say 07-30-00,?
     
    Last edited: Oct 15, 2015
  5. Sugandh Sachdev

    Thread Starter New Member

    Oct 15, 2015
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    yep
     
  6. djsfantasi

    AAC Fanatic!

    Apr 11, 2010
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    And how are you going to input the alarm time? Sets of SPST switches for each digit? A four position DIP switch? A thumb wheel BCD switch? The last is easiest, but is expensive.
     
  7. Sugandh Sachdev

    Thread Starter New Member

    Oct 15, 2015
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    dip switch
     
  8. djsfantasi

    AAC Fanatic!

    Apr 11, 2010
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    So you set a DIP switch for each digit. What do you want to compare it to? For example, consider just the 10s of minutes digit?

    By the way, have you simulated your circuit?
     
  9. Sugandh Sachdev

    Thread Starter New Member

    Oct 15, 2015
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    OHH I think I got it.
    Compare it with the current time. when the the current time and the input in dip switch matches a buzzer is activated.
    Thanks for the help
     
  10. crutschow

    Expert

    Mar 14, 2008
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    Just be sure you don't take it to school to show a teacher. :rolleyes:
     
    ISB123 likes this.
  11. djsfantasi

    AAC Fanatic!

    Apr 11, 2010
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    Have you simulated this? I had a reason for asking before.

    I suggest you do, even if you run through it manually. I have a suspicion...

    Your minutes and seconds may only count up to 58, leaving you a a few seconds short of a minute and a few minutes short of an hour...
    It will be a fast clock. Depending on what you're using it for, it could be a good thing or a bad thing.
     
  12. Sugandh Sachdev

    Thread Starter New Member

    Oct 15, 2015
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    Yes. It works fine till 60 minutes. The hours one I haven't really simulated that
     
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