BUILTIN LED WILL BLINK BUT CAN'T GET PIN TO OUTPUT

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robintwhite
 
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BUILTIN LED WILL BLINK BUT CAN'T GET PIN TO OUTPUT

Post by robintwhite »

I am starting the Experimenters guide with Metro on Windows. I have followed the steps and uploaded to the Metro via Arduino IDE. I can change the timing of the blink test for the built-in LED and it uploads fine and behaves without issue however when I try to have an external LED work as described in the tutorial (https://learn.adafruit.com/experimenter ... 01-code%20) the LED does not light up and only the internal LED blinks. I have tried everything for drivers, boards etc but nothing works. I tried different pins but no matter what pin, no matter digital write or analog I can't get the external LED to turn on. Using pin 13 instead of LED_BUILTIN still has the 'L' LED blink. Changing pins and in the code, obviously for example to pin 9 still does not change anything and the 'L' LED no longer blinks, so something is happening. I don't know how to troubleshoot this further and can't find any information online.
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dastels
 
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Re: BUILTIN LED WILL BLINK BUT CAN'T GET PIN TO OUTPUT

Post by dastels »

The "L" LED is connected to D13 (aka LED_BUILTIN) so the behavior regarding it is expected.

As to why the external LED isn't lighting. This could be various things. Have you:
- verified that the LED is in the right way round?
- tried reinserting the wires/parts in the breadboard or moved them to a different spot on the breadboard (occasionally you'll have connection issues)?
- tried replacing the LED?
- tried replacing the resistor?

Try one thing at a time and retest.

Dave

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robintwhite
 
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Re: BUILTIN LED WILL BLINK BUT CAN'T GET PIN TO OUTPUT

Post by robintwhite »

That worked thank you - looks like it was a dead LED

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dastels
 
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Re: BUILTIN LED WILL BLINK BUT CAN'T GET PIN TO OUTPUT

Post by dastels »

Awesome! Have fun.

Dave

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