Connect with us

7 segment display

Discussion in 'General Electronics Discussion' started by Springcone710, Dec 16, 2013.

Scroll to continue with content
  1. Springcone710

    Springcone710

    4
    0
    Dec 16, 2013
    Hi,

    I'm wanting to build a simple lap counter for my nephews scalextrics! I want it to be as simple as possible and if I can, I would prefer not to use adruino!

    Does anyone know if it's possible to make the 7 segment display count up and cycle back to 0 with just 1 switch? If so, how?

    I want to put the snap action switch in the groove on the scalextrics so that when the car passes the start/finish line, the cars leg that fits in the groove will press the switch and the 7 segment display will change!

    Thanks, chris
     
  2. (*steve*)

    (*steve*) ¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd Moderator

    25,418
    2,788
    Jan 21, 2010
    Fairly simply, you could connect a counter with a bcd output to a bcd to seven segment decoder, and that to a seven segment display.

    The switch generates the clock signal which increments the counter. You'd probably wire up the reset line so you could push a button to reset the counter(s).

    The main problem is the switch. Switches bounce, so you would need to de-bounce it so that each press generated just on clock pulse, and therefore just increments the counter by 1.

    Chips you might be looking at are a 40106 (hex schmitt trigger) to be part of a circuit to debounce the switches, a 4511 BCD to 7 segment decoder/driver, and a 4510 BCD up/down counter.

    The use of a BCD counter eliminates problems with values 10 to 15 which can't be displayed on a single digit. This also allows you to cascade them for 2 or more digits.

    Oh, note that you need common cathode displays.
     
  3. ziin

    ziin

    9
    0
    Dec 2, 2013
    It depends on what chip you prefer to use? Two of my favorite chips are Microchip and Arduino.

    If you want to use Microchip, I can give you more advice.
     
    Last edited: Dec 19, 2013
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day

-