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Looking to make a simple LED scoreboard?

Looking to make a simple LED scoreboard for scoring "Bags" games (Cornhole). All i Need is 2 rows of 21 LEDS on each side of a vertical board with the bottom denoting scoring "1" and the top as "21". And I'd like to have some sort of momentary button to press that would move the circuit from 1 to 21 one increment at a time (moving up, turning on the next as the last one turns off). I could just put switches on each led but I am trying to avoid that. Any advise would be helpful. Thanks

PS , if all the lights stay on until i get to the top and then able to reset it, that would be fine too, Just trying to eleviate the use of multiple toggle switches.

You could connect 3x 8-bit shift registers together to make a single long one. Connect all the clock inputs to one button, and all the resets to another, then if the input is held at 5V the bar will lengthen by 1 LED each time the button connected to the clock inputs is pressed. The bar will clear when the reset button is pressed.
djtonyc77 (author)  The Skinnerz1 year ago
not familiar with 8 bit shift registers, but willing to learn. Just curious as to where to connect the LEDs then. Thanks. maybe a simple schematic if you can.
Generally, a serial-in, parallel-out shift register has two main inputs: data and clock, and many outputs (an 8-bit register has 8 outputs). Every time the clock pin goes high, the outputs all move along one pin and the value on the data pin is moved to the first output pin.

You can make longer shift registers by joining the last output of one to the data pin of the next, and connecting all the clocks and resets together. You would connect the LEDs to the outputs with suitable resistors.

By holding the input of the first register high, you are feeding a continuous bar into the register.
frollard1 year ago
42 is a bit big to consider for a single bar graph...

It could be done with a binary up counter IC...would need at least 7 bit digital output, then feed the binary output from the counter to a demultiplexer/bar graph driver.

Long story short, thats a lot of leds for a beginner project. I'd recommend using something like an arduino or other microcontroller to run a program and then simply run a matrix of leds; a lot less designing, a lot more using.
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