Halo 4 has “7” Terminals, keep in mind, that at the end of all of these there is an incomplete code; 1w286 (Translation)
Although, ever think that maybe the Forerunner codes we’ve been finding through the recent Didact visits on Waypoint, Xbox.com, IGN, etc all can be put together to form the FULL Code that can be entered on Waypoint to unlock the 8th Terminal? (If there is one of course 
all speculation, but a good one I think)
Here is the Code form the Terminals;
1w286
Here is the Codes we’ve been finding in recent videos/ on recent websites;
_ 5 C _ 6 K V 3 _ 8
_ C2 _
Q _ 2 P _
(Here it is bunched together: C 3 K 8 5 P 2 6 Q C2 V)
Anyway, I hope this may or may not help with ideas and speculation.