I currently have a self designed I/O board. I'm using the LPC1768FBD100 Microcontroller NXP 3V3 and created 20 inputs and 14 outputs. My design allows only inputs to be inputs and outputs to be outputs. Below you can see the input and output part.
So right now I have dedicated output pins and input pins What I would like to know is, What do I have to do electrically if I want to make a pin to be both Input and Output. Can I just connect the end of the input circuit to the I/O port and the beginning of the Output to the same I/O and add something extra electrical components to make that work, or do I have to change the complete circuit? Is there someone with an example or information about this?