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I was reading microntroller datasheet, they mention any I/O pins can be configrued as Open drain , or as Special pheripheral ( like SPI , I2C etc..) or push pull.
Q) Can we enabled microcontroller internal pull up when pin is configured as output only.
Q) when open drain selection need to choose wheather pin is input or output.
Q) Can we use both internal and external pull on some IO line , then it can be nay problem