I read the Arduino official docs on digitalWrite and am confused about what is happening from an electrical perspective when digitalWrite is invoked on INPUT_PULLUP pins.
Say my code says this:
pinMode(4, INPUT_PULLUP); digitalWrite(4, LOW);
The docs say:
If the pin is configured as an INPUT, digitalWrite() will enable (HIGH) or disable (LOW) the internal pullup on the input pin. It is recommended to set the pinMode() to INPUT_PULLUP to enable the internal pull-up resistor. See the Digital Pins tutorial for more information.
Does this mean pin 4 is floating or is it at ground? Are those two lines of code equivalent to
pinMode(4, OUTPUT); digitalWrite(LOW); ?