upper memory blocks การใช้

Later, space between the holes would be used as upper memory blocks ( UMBs ).
The next stage in the evolution of DOS was for the operating system to use upper memory blocks ( UMBs ) and the high memory area ( HMA ).
Additionally, on Intel 80386 machines, DR DOS's EMS memory manager allowed the OS to load DOS device drivers into upper memory blocks, further freeing base memory.
DOS 5 supported the use of the High Memory Area ( HMA ) and Upper Memory Blocks ( UMBs ) on 80286 and later systems to reduce its conventional memory usage.
These memory areas are referred to as the high memory area ( HMA ) and the upper memory area ( UMA; also referred to as upper memory blocks or UMBs ).