Int 31 Fn 050A P - Dpmi 1.0+ - Get Memory Block Size And Base [E]
AX = 050Ah
SI:DI = memory block handle
Return: CF clear if successful
SI:DI = size in bytes
BX:CX = base address
CF set on error
AX = error code (8023h) (see #2814)
See Also: AX=0501h,AX=0504h