Bitfields for CardBus Socket Event Register:
Bit(s)	Description	)
 0	CSTSCHG pin asserted (status change)
 1	CCD1# (card detect 1) changed state
 2	CCD2# (card detect 2) changed state
 3	interface power cycle completed
31-4	reserved (0)
Note:	the bits in this register are set by the bridge, and cleared by writing
	  a one into the bits one wishes to clear
SeeAlso: #00890,#00893,#00895