Are you asking for a button specific to weapons to cycle weapon combinations for the primary trigger to fire? Or do you simply want everything fired by the joystick trigger toggled for fire selection to that trigger by a single second button?
A.) Toggle Button Cycle Programmable List
Fire All = 1
Fire Primary = 2
Fire Secondary1 = 3
a = (Primary)
b = (Secondary guns)
c = (Secondary rockets)
Fire Secondary2 = 4
a = (Secondary guns)
b = (Secondary bombs 1)
c = (Secondary bombs 2)
B.) Toggle Button Cycle Programmable List
Fire All = 1
Fire Primary = 2
Fire Secondary = 3
Fire Secondary Bombs1 = 4
Fire Secondary Bombs2 = 5
Fire Secondary rockets = 6
Fire Secondary Drop Tanks = 7
In WW2 the closet thing to this was the german Knuppelgriff. Knopf FT, A, B1, and B2 along with P(x) buttons strapped on to it to cover multiple kits and additional functions. In many cases fire all was holding down two buttons at the same time. While the addon kits or bombs were separated to individual function on individual buttons.
Would it not be easier to ask for all weapons(guns, bombs, rockets, DT) to be cycled by a single button, then fired or dropped by the primary joystick trigger? And how far back into the 1990's do you want to go with our game?