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Function RTSetBootParams

Function RTSetBootParams can supply a few parameters the boot code Biosboot.exe usually retrieves from the BIOS:

void RTSetBootParams(int GMode, DWORD ExtMem, void * VideoRAM);

Parameters

GMode

The value to be returned by future calls to function RTGetGMode. If zero is specified, the current GMode value held by the boot code is not changed.

ExtMem

The value to be returned by future calls to function RTGetExtMem. If zero is specified, the current extended memory size held by the boot code is not changed. Please note that function RTCMOSExtendHeap uses RTGetExtMem internally.

VideoRAM

The value to be returned by future calls to function RTGetVideoRAMAddr. If NULL is specified, the current video RAM address held by the boot code is not changed.

This function can be useful for programs booting through boot code BIOS.EXE or PMBOOT.EXE as these boot codes cannot retrieve these parameters from the BIOS. However, once RTSetBootParams() has been called, functions RTGetGMode, RTGetExtMem, RTCMOSExtendHeap, and RTGetVideoRAMAddr can be used. Program Application.cpp of demo project FTPLoader shows how this function can be used in an Init function.

Function RTRestoreBootSector

Function RTGetBIOSDataPtr