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Contents Programming For ISA Hardware Overview Programmers Guide Scenario I/O Ports control Single read/write operations Data array read/write operations Accessing Physical Memory Addresses Memory Mapping Additional Functions Hardware interrupts handling at user level Common Functions OpenRapidIsa CloseRapidIsa IsRapidIsaOpened GetHardwareConfiguration Direct Port I/O GetPortByte GetPortWord GetPortLong SetPortByte SetPortWord SetPortLong ReadPortBuffer WritePortBuffer Memory Access MapPhysToLinear UnmapMemory GetMem GetMemW GetMemL SetMem SetMemW SetMemL Hardware Interrupts UnmaskIsaIrq MaskIsaIrq GetInterruptCounter		Memory Mapping Go to RapidDriver Main Page To access specified physical memory address you have to map this physical address to a linear memory of the current process' address space. RapidIsa includes the function MapPhysToLinear, which performs the above task and returns the pointer to the above linear memory defined by it's physical address and size. When the pointer is not needed by application any more, this physical memory area can and must be unmapped with the function UnmapMemory. The following is an example how to get a pointer to the ROM BIOS area: char *pBios;   HANDLE hIsa = NULL;   hIsa = OpenRapidIsa( 0 );   if (IsRapidIsaOpened(hIsa))    {     pBios = (char*)MapPhysToLinear(hIsa,0xF8000,256); //256 bytes, starting from 0xF8000     //...pBIOS session...     UnmapMemory(hIsa, 0xF8000,256); // undo mapping     hIsa = CloseRapidIsa(hIsa);     //  close the driver   }   else      ... // failed