INT 2F - DOS Protected-Mode InterfaceAn API which provides basic services for protected-mode programs to allocate memory, invoke real-mode software, etc. See also Virtual Control Program Interface. - INSTALLATION CHECK AX = 1687h Return: AX = 0000h if installed BX = flags bit 0: 32-bit programs supported CL = processor type (02h=80286, 03h=80386, 04h=80486) DH = DPMIsee DOS Protected-Mode Interface major version DL = two-digit DPMIsee DOS Protected-Mode Interface minor version (binary) SI = number of paragraphs of DOS extender private data ES:DI -> DPMIsee DOS Protected-Mode Interface mode-switch entry point (see #02718) AX nonzero if not installed SeeAlso: AX=1686h,AX=43E0h,AX=DE01h/BX=4450h,AX=FB42h/BX=0001h SeeAlso: INT 31/AX=0400h,INT 31/AX=5702h,INT D4/AH=10h (Table 02718) Call DPMIsee DOS Protected-Mode Interface mode switch entry point with: AX = flags bit 0: set if 32-bit program ES = real mode segment of buffer for DPMIsee DOS Protected-Mode Interface private data (ignored if SI was zero) Return: CF set on error program still in real mode AX = error code (DPMIsee DOS Protected-Mode Interface 1.0+) 8011h unable to allocate all necessary descriptors 8021h 32-bit program specified, but 16-bit DPMIsee DOS Protected-Mode Interface host CF clear if successful CS = 16-bit selector corresponding to real-mode CS SS = selector corresponding to real-mode SS (64K limit) DS = selector corresponding to real-mode DS (64K limit) ES = selector to program's PSPsee Program Segment Prefix (100h byte limit) FS = GS = 0 high word of ESP = 0 if 32-bit program program now in protected mode Note: this entry point is only called for the initial switch to protected mode