GPIO pins in embedded board

[nahidalam]

I am exploring the capabilities of GPIO pins in the embedded development boards.

Is it possible to connect 1 GPIO pin to multiple devices? Do I need to use some sort of port expander.

 

[shaiko]

Generally speaking,

When configured as output, it is possible to drive multiple destinations with a single pin (without exceeding the maximum current drain of the port of course).

When configured as input, only one source can actively drive the pin - otherwise, conjunction will occur.

This is the general rule (exception do exsist).

 

[horace1]

I am exploring the capabilities of GPIO pins in the embedded development boards.

Is it possible to connect 1 GPIO pin to multiple devices? Do I need to use some sort of port expander.

using wired-OR, open collector or tristate techniques can enable multiple devices to use a common line, e.g.
https://www.ni.com/white-paper/3544/en/

if using an microcontroller GPIO pin you have to ensure that it has this capability