INT 11 - BACK&FORTH (before v1.62) API AX = FFFEh CX = FFFEh BX = function 00h installation check Return: AX = installation state 0001h BNFHIGH and BNFLOW both loaded 0003h only BNFHIGH loaded else neither loaded 01h ??? Return: DX:AX -> ??? 02h ??? 03h ??? 04h ??? 05h ??? switches current PSP segment and stack if BNFLOW has not yet announced itself installed 06h ??? Return: AX = ??? SeeAlso: INT 12/AX=FFFEh Index: installation check;BACK&FORTH