Controlling a 433 mhz projector screen but missing codes

Hi,

I have purchased an 433 mhz rf kit for my Raspberry PI 3 and it works fine. I want to control my projector screen but I have lost the remote for it so I cannot read the codes from it.

Is there a standard range of codes that cover screens or is there another way I can find out which the codes are?

Cheers,