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GPIO: Digital I/O
Reading buttons and driving LEDs: configuring a pin's direction, push-pull vs open-drain outputs, pull-up/down inputs, and why a floating input reads noise.
22 min read
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What's the difference between push-pull and open-drain outputs?Why shouldn't you leave a GPIO input floating?You configured a GPIO pin correctly but it does nothing. What's the first thing to check?What is switch bounce and how do you handle it?How do you use a GPIO pin for a peripheral like UART TX instead of plain output?
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