INT 15,87 - Move Block to/from Extended Memory

	AH = 87h
	CX = word count of block to be moved
	ES:SI = pointer to Global Descriptor Table (GDT)


	on return:
	CF = 0	if successful (AH contains return code)
	   = 1	if error detected
	AH = 0	operation successful (ZF also set)
	   = 1	RAM parity error  (if CF set)
	   = 2	other exception (if CF set)
	   = 3	gate address on line 20h failed (if CF set)
	   = 80h on PC and PCjr (if CF set)
	   = 86h on XT and newer 808x machines (if CF set)

	- transfers data blocks to and from extended memory on 80286
	  and 80386 machines by switching from real to protected mode
	  for the duration of the transfer
	- all real mode interrupts are disabled
	- processor shuts down during the switch from protected mode
	  to real mode on 286 processors