INT 2F - Multiplex - ??? - INSTALLATION CHECK??? AX = E700h BX = 4158h ("AX") CX = 4953h ("IS") DX = 4845h ("HE") Return: AL = FFh if installed BX = 4C4Fh ("LO") if ??? installed CX = 4F4Bh ("OK") DX = 4F55h ("OU") ES:DI -> ??? Range: AH=C0h to AH=FFh, selected by scanning AH=E7-FFh, then AH=C0h-E6h Note: called by QDPMI when its Real to Protected ModeOne of the operating modes of the 80286 and higher Intel processors, in which addresses used by programs no longer correspond to physical addresses and the CPU enforces various protection mechanisms designed to prevent one program from disrupting other programs or the operating system. See also Real Mode, Virtual-86 Mode. Switch Entry Point is called