Each time I press a particular button in my circuit the red RX light flashes briefly.

I have been having trouble with making this button perform the command it should, I and am wondering if the RX flash has something to do with that, or is at least reporting some sort of error?

  • 3
    Leds? Buttons? Which is it? Also, what the frog is a "red board", and what is this mystery circuit you have? And while you're at it, what code is supposedly trying to perform a "command"?
    – Majenko
    Commented Jun 11, 2017 at 21:03
  • Welcome to Arduino beta. Please take the tour to get the most out of this site: arduino.stackexchange.com/Tour - You will notice the downvotes because of the way your question is formatted. Take the tour and perhaps you can edit in a way that will attract answers.
    – SDsolar
    Commented Jun 12, 2017 at 1:41
  • The red light is flashing because you are pressing the button. To stop the red light flashing I recommend not pressing the button. Commented Jun 12, 2017 at 8:25

1 Answer 1


The TX LED is there to show that some data or signal has been received on your Arduino. When you press the button on your circuit, it briefly sends a signal which then triggers the RX LED on your Arduino. Most often, the RX LED is used to troubleshoot whether you are receiving an input and, in your case, it seems you are.

Therefore, the RX LED is not an error and shouldn't be the source of your problem.

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