)
Values for speed code:
 00h	equivalent to 6 MHz 80286 (COMMON)
 01h	equivalent to 8 MHz 80286 (FAST)
 02h	full 16 MHz (HIGH)
 03h	toggles between 8 MHz-equivalent and speed set by system board switch
	  (AUTO or HIGH)
 08h	full 16 MHz except 8 MHz-equivalent during floppy disk access
 09h	specify speed directly