P In and P Out connections on DMX Module

[bassman59]

Hi All,
Newbie!!
I had to choose a Software (Quick DMX) to register here but I'm not using any software yet.
Interested in DMX for a stage setup. I'm a maker and an engineer (electronics) I see cheap modules on Ali that might be useful. They have the usual Data and RGB pins for DMX linking but also have two pins marked P In and P Out. Are these used for automatic addressing of some kind. P Out is linked to P In of the next module etc but one diagram shows the first P In connected to a DMX controller. This pin is not included in any standard DMX connector cable I have seen so far. I'm sure I don't need to use P In & P Out, if I program addresses via the software and A B network but I'd like to know what it is.
I'm sure one of you guys do and any help greatly appreciated.

Module Link:
https://www.aliexpress.com/item/1005003 ... f19cIOhF2a


Thanks
Ed

[moved by support in this section]