)
Call the Netroom RM386 v6.00 "Create new UMB entry" function with:
AH = 83h
BX = segment of high-memory block
DX = first page of start of block
CX = number of consecutive pages in block
DI = start of UMB in block
Return: AX = 0001h (success)
DI = segment of first high-DOS block
Note: the new UMB is not linked into the high-memory chain
SeeAlso: #02766,#02784,#02786