Raspberry Pi of Goemon

Raspberry Pi3 learning blog

Beginner Electric work

Utilize an internal pull-down resister

Post:03/10/2016 Update:

In the previous post, I checked how a pull-down resister functioned. When it’s there the system worked as expected. However once it’s taken off, then LED became unstable. Actually, Raspberry Pi 3 contains an internal pull-down resister and you can enable it by coding. Today, I’m gonna show you how you can enable an internal resister and how it works. Don’t worry, it’s very simple 🙂

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Utilize an internal pull-down resister

In the previous post, I modified the line 8 of code as below.

This is whole the code.

By adding the one line, the internal pull-down resister worked and the system functioned well without 10kΩ resister for pull-down.

img_20161003_023407

This is how it looks like. Is it beautiful, isn’t it? This kind of simple setting gives me lots of insight. What simple is more general and can be applied broad range of things.

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-Beginner, Electric work
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