Dumb question about built in LED

Normally the red LED on the nano rp 2040 connect is not on but now it is on and stays on. I am able to upload and my sensors are doing fine. I am using D13, is that why it wont turn off? I tried unplugging the wire at D13 but it stayed on. Is there any reason to worry?

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Does your code sets D13 as an output and HIGH? There is no need for an external wire as the trace to the led and its current limiting resistor is hardwired on the board itself

Ahhh good catch I was trying to use it as an INPUT and forgot to take it out of the code. Thanks

So i took it out of the code and it is still on. Is there any reason for me to worry?

Ah missed the rp 2040 connect

Can you clarify which led you are talking about?

If you are taking about the power led then you can’t turn it off. You have to physically remove it or its resistor if you don’t want it.

The RGB led can be driven by code but is not on pin 13 (which also serves as SCK)

the LED_BUILTIN on the right side

Try to upload a small code playing with that led and see if all works fine.

There are many examples on line, here is the first Google hit

I am trying to find something on google for this issue but I am surprised there isn't much coming up. Ill take a look at what you posted, thanks.

So I figured out why now, I am using the D13 pin as a digital pin on that side of the board for my DHT-11. I forgot that I changed it so I can have the sensor on that side of the board. I cant seem to figure out how to make an analog pin become a digital pin so I had to use it.

I don’t get what you are saying - can you post your schéma ?

Did you try the example ?

Wait one and Ill make a schematic

LOL I have no idea how to make a schematic but I was reading that the builtin led is attached to D13 pin. I have never used that pin before but now that I am its lit up and it just so happens one of my sensors, physically and in the code is using it so it is lit up.

Not on that board - you probably read that for the original Nano

Ah man you are right. Back to Google. Damnnit lol '

the LED_BUILTIN is on pin 13

Nice! I thought so because this was the first time using it and it was too coincidental, plus it is on the UNO so I mean I knew there was a good chance. Thank you for the clarification.

Yes it is connected to pin D13

My bad - I thought that it was an RGB LED here

//#define LEDR        (20u)
//#define LEDG        (21u)
//#define LEDB        (13u)

Gentlemen, please note that the Arduino IDE has plenty of example sketches. One that I often use to test an Arduino is BLINK:
Arduino IDE - in the menu; File --> Examples --> 01. Basics --> Blink.

Blink can be used to test any pin; default is the build-in led on pin 13
Voila!

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