bergzwerver · 7-Year Club · 2 points · *
I think the figures are just showing the concept of pull-up and pull-down resistors. Both concepts are commonly used, and serve the same purpose in different contexts of prevent floating, undefined voltage like you mentioned.
A microcontroller input has high impedance, so the resistor does not serve a purpose of limiting current here. The only way this would not be the case is if you were to configure internal pull-downs, but that would make no sense in the context of this figure.
The context in which they are applied here are called open-emitter and open-collector inputs respectively.
A microcontroller input has high impedance, so the resistor does not serve a purpose of limiting current here. The only way this would not be the case is if you were to configure internal pull-downs, but that would make no sense in the context of this figure.
The context in which they are applied here are called open-emitter and open-collector inputs respectively.
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