Reading GPIO pin as an INPUT on Raspberry PI

[Awesome Programmer]

Hi, I am working on Pi 3 and I want to be able to read GPIO pin 2 for its state or status every 3 seconds or so. I've been looking around for solution and I don't know which direction to take. I've tried their example or sample codes and I am either more confused or don't understand their code. I want to be able to get Direct Access to the pin state using BaseUnix, but I can't seem to understand their sample code; they are talking about setting the pin 2 as OUTPUT to read it as INPUT. If someone could give me a very simple sample code that only reads GPIO Pin 2 for its status and displays it or does writeln, it would be very helpful.

Thank you.

[ccrause]

It isn't clear what example you are referring to.

There is a wiki example that describes how to read a pin.  Perhaps test the wiki example, then ask here if you need further help/clarification.

[Thaddy]

It is as easy as knowing the virtual pin starting address and using the type helpers for bit manipuation
That address varies among Raspberry versions but is documented on the Raspberry Pi website.
<address>.Setbit/togglebit etc. I can post a complete example for it if you want.
Actually, I wrote the helpers with my Raspberry Pie's in mind and it works quite good...
(Note that Avra extended the bit manipulation helpers so you may want to examine his new options too )
(Also note I never tested this for AARCH64 on RP3, but I did for RP4, the code assumes a 32 bit value, I tested it on all 32 bit types since RP1 )