Int 2F/AX=1687h

DOS Protected-Mode 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 = DPMI major version
DL = two-digit DPMI minor version (binary)
SI = number of paragraphs of DOS extender private data
ES:DI -> DPMI mode-switch entry point (see #02718).
AX nonzero if not installed

See Also: AX=1686h - AX=43E0h - AX=DE01h/BX=4450h - AX=FB



(Table 02718)
Call DPMI mode switch entry point with:.
AX = flags
bit 0:
Set if 32-bit program.
ES = real mode segment of buffer for DPMI private data (ignored if
SI was zero)

Return:
CF set on error
program still in real mode
AX = error code (DPMI 1.0+)
8011h unable to allocate all necessary descriptors
8021h 32-bit program specified, but 16-bit DPMI 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 PSP (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

Category: DOS Extenders - Int 2Fh - D

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