MEM 80C00000h - COMPAQ DIAGNOSTICS REGISTER                                     
Size: WORD
Note:	Writing to F000h:FFE0h seems to involve unlocking the memory by writing
	  FEFEh to this address first. The write-protection can be
	  reestablished by writing FCFCh to this address???  This was seen done
	  by MS HIMEM.SYS.
SeeAlso: F000h:FFE0h


Bitfields for Compaq Diagnostics Register:
Bit(s)	Description	(Table M0132)
 15-10	unknown purpose (should remain set???)
 9	=1 memory is read-write???
	=0 memory is read-only???
 8	=1 to disable ROM(Read-Only Memory) A memory for program storage which may not be changed by the program as it runs. replacement???
	=0 normal???
 7-2	unknown purpose (should remain set???)
 1	=1 memory is read-write
	=0 memory is read-only
 0	=1 to disable ROM(Read-Only Memory) A memory for program storage which may not be changed by the program as it runs. replacement???
	=0 normal
Note:	Writing to F000h:FFE0h seems to involve unlocking the memory by writing
	  FEFEh to this address first. The write-protection can be
	  reestablished by writing FCFCh to this address??? 
	  Microsoft HIMEM.SYS was seen to do this.
SeeAlso: F000h:FFE0h