Typing with external device

Hi all,

In the Carenado Phenom 300 there's a GCU for flight planning. Part of this is a keypad with letters and numbers. In the sim this replicates my main pc keyboard. I.e i can type the letter A either by using the gcu keypad or my main keyboard.

My question is this: How do i assign the typing of letters on an external device such as a Leo Bodnar i/o card.(actually push button switches attached to this card)

Cheers

Stinger

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