OK, now I'm starting to think this keyboard is borked. Thanks guys, appreciate the responses.
test the keyboard on a pc or laptop or other console, then you know if it's working as designed. if it is, try to plug a controler in the usb port on your ps4 which you used for the keyboard (or any other device compatible with ps4) to ensure the port is not broken. lastly, if your keyboard is ps/2 (not talking about the ps2 but the ps/2 port system used on old pcs) and you use a ps/2-to-usb adapter, then i'm afraid it's not compatible with ps4 (from my experience).
I hope that helped.
Edited by Eshenya on 14 July 2017 11:36
This one does not appreciate txt tlk, elitism and foul language.