[1.12] Block update in loaded chunk

[Damon]

Heya, im fairly new to modding mincraft and cannot bring google to give me results for my question. 

Let's assume I want to create a block which I want to update every tick whilst its chunk is loaded.

 

Which approach would be best suited?
Where can I read more about the Block Update and Chunk loading mecanics, for further reference?

 

Thanks in advance!

 

Edited February 5, 2018 by Damon
Corrected heading (once again)

[Damon]

1 minute ago, diesieben07 said:

In your title you say "unloaded", in your post you say "loaded", which one do you mean?

If you mean loaded: Use a TileEntity.

If you mean unloaded: Well, you can't really tick a block that is not loaded. What are you trying to do in this update?

My bad, corrected it.

Well, I wanna update a simple value which is depending on the current weather/game time and block position.