INT 11 - RainbowFAX v1.3 - SFENGINE API - ???
        AH = 78h
        AL = subfunction
            7801h set ???
                BX = new state for ???
                    0000h ???
                    else ???
                Return: AX = 0001h
            7802h set ???
                BX = ???
                CX = ???
                Return: AX = 0001h
            7803h set ???
                BX = new state for ???
                    0000h ???
                    else ???
                Return: AX = 0001h
            78XXh invalid subfunction
                Return: AX = FFFFh
SeeAlso: AH=77h,AH=79h,AH=7Ah,AH=7Ch

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