Int 1Ah Function 5650h (Preboot API Installation Check)

Enter:

AX := 5650h (VP)

Exit:

AX := 564Eh (VN)

ES := 16-bit real-mode segment of the preboot API entry point structure.

BX := 16-bit real-mode offset of the preboot API entry point structure.

EDX := 32-bit physical address of the preboot API entry point structure.

All other register contents are preserved.

CF is cleared.

IF is preserved.

All other flags are undefined.