TIMER panel for MP3 Board

Ive made a Buzzer with the dome pushbutton, and an MP3 Board.

Now I´d like to add LED DIGITS that display time past with Large 7 Segment Display digits (6,5").

Id like to have the timer be able to turn on remotely (from start position), and be stopped by push-button buzzer (goal).

  1. a person by the start-line starts the time.

  2. a person reaches the finish line and stops the time by push button

  • Start and finish line are within 500m of each other.

How can I make this possible?

Its for use in outdoor Ninja Warrior competitions.

Hi Kim.

This could be tricky because of the distance between the two buttons and you’re probably going to need some sort of wireless link between those.

What I’d suggest is building this in small scale first where you have you digits, controller and the start and stop buttons close together to work out your code and make sure it functions correctly. Once everything is working, then start developing a wireless ‘start’ button that can communicate back back to the controller.

For a controller and digits, the following parts might work for you:

  • - [[SparkFun RedBoard](https://www.sparkfun.com/products/15123)
  • - [[SparkFun Large digit driver](https://www.sparkfun.com/products/13279) (one per digit)
  • - [[6.5" Seven Segment displays](https://www.sparkfun.com/products/8530)
  • - [[12 volt power supply](https://www.sparkfun.com/products/15701) (for controller and digits)
  • - Any kind of buttons you want to use, [[Big Domes](https://www.sparkfun.com/products/9181) would work.
  • [/list]

    Making things wireless is where this gets tricky. You need a pair of radios that have the range you’re looking for. I haven’t tested the range on our XBee transceivers, but the manufacturer states a range of up to 2 miles outdoors with the proper antenna. (Generally, you can cut the range in half in a real world application.) We don’t have a guide for how to setup the XBees we carry for a wireless button, but with the right programming and connections, a pair of the parts below might work for you. (You’d need to test the range and figure out how to program the XBees for ‘line passing mode’.) Digi [has a tutorial here for an older model XBee but you might be able to adapt that for the newer XBee we carry.

  • - 2x [[XBee 3 Pro Module - RP-SMA Antenna](https://www.sparkfun.com/products/15131)
  • - 2x [[2.4GHz Duck Antenna RP-SMA - Large](https://www.sparkfun.com/products/558)
  • - 2x [[Breakout Board for XBee Module](https://www.sparkfun.com/products/8276)
  • - 4x [[2mm 10pin XBee Socket](https://www.sparkfun.com/products/8272)
  • - [[3 volt battery pack](https://www.sparkfun.com/products/9547) for powering the remote button.
  • [/list]

    You will need to write your own code to get this working and unfortunately we can’t assist with the code, but I recommend breaking your project down into steps and getting each step working before trying to combine them all. That way, errors in your code are easier to find and fix. :-)](https://www.sparkfun.com/products/9547)](https://www.sparkfun.com/products/8272)](https://www.sparkfun.com/products/8276)](https://www.sparkfun.com/products/558)](https://www.sparkfun.com/products/15131)](Wireless Control of AC Devices with a PowerSwitch Tail | Digi International)](https://www.sparkfun.com/products/9181)](SparkFun ATX Power Connector Breakout Kit - 12V/5V (4-pin) - KIT-15701 - SparkFun Electronics)](https://www.sparkfun.com/products/8530)](SparkFun Large Digit Driver - WIG-13279 - SparkFun Electronics)](SparkFun RedBoard Qwiic - DEV-15123 - SparkFun Electronics)