Bitfields for Intel 82371MX Local Trap Mask for Device 3 register:
Bit(s)	Description	)
 7-4	Local Trap COM Port Select
	=1000	COM4 02E8h-02EFh
	=0100	COM3 03E8h-83EFh
	=0010	COM2 02F8h-02FFh
	=0001	COM1 03F8h-03FFh
Note:	These bits when set cause an SMI# when access to the corresponding I/O
	  port range is made.
 3-0	Local Trap Mask
Note:	This field selects the range of trappable addresses (in bytes).
SeeAlso: #01168,PORT xxxxh"Intel 82371"