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Author Topic: Pin issue  (Read 265 times)
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Hi everyone!

Every pin on my arduino works fine but when i set this

Code:
pinMode(13, INPUT);
digitalWrite(13, HIGH);

the tiny LED on the board near TX/RX LEDs is dimmed on..

Lucky number 13 ????

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weak pull-up.
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As dhenry is trying to explain, doing that turns on the internal pull-up, which effectively connects the on-board LED to 5V via about a 50K resistor.
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As dhenry is trying to explain, doing that turns on the internal pull-up, which effectively connects the on-board LED to 5V via about a 50K resistor.

That shows how efficient modern day leds can be where even 100 micro-amps can generate some light!

Lefty
« Last Edit: November 18, 2012, 11:36:55 am by retrolefty » Logged

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