Bitfields for MS-DOS v6.22 KEYB flags A:
Bit(s)	Description	)
 15	unused??? (0)
 14	set on machine with BIOS machine type FBh or FEh/FFh without enh kbd
 13	not FAh: ???
 12	set on start of machine detection, cleared on machine types F9h, FBh,
	  FEh, FFh
 11	not FAh: ???
	(on ATs: override bit12 NOT to set NumLock on)
 10	set on machine type F9h
 9	unused??? (0)
 8	unused??? (0)
 7	used by INT 09, but never set!
	=1: after keyboard self test resulting AAh, INT 09 handler will (re)set
	      keyboard code-set 1 and temporarily disable a PS/2 mouseport.
 6	used by INT09, but never set!
	=1: after keyboard self test resulting AAh, INT 09 handler will (re)set
	      keyboard code-set 1 and temporarily disable a PS/2 mouseport.
 5	set for JP, KO, PR, TA layouts during installation???
	=1: some special codepage (>932???) management???
 4-0	unused??? (0)
SeeAlso: #02974,MEM F000h:FFFEh,INT 15/AH=C0h