Bitfields for Intel 82437VX,82439HX/TX PCI Control register:
Bit(s)	Description	)
 7-4	reserved (82437VX,82439TX)
 7	DRAM ECC/Parity Select (82439HX)
	=1 ECC
	=0 parity
 6	ECC TEST enable (82439HX)
 5	shutdown to port 92h (82439HX)
	=1 send 01h to PORT 0092h on Shutdown special cycle on host bus
 4	dual-processor NA# enable (82439HX)
 3	PCI Concurrency Enable
	=1 CPU can access DRAM/L2 during non-PIIX PCI master cycles
	=0 CPU kept off PCI bus during all PCI bus-master cycles
 2-0	reserved (82437VX,82439TX)
 2	SERR# Output Type (82439HX only)
	=1 SERR# is actively driven high when negated
	=0 SERR# is PCI-compatible open-drain output
 1	reserved
 0	Global TXC Enable (82439HX only)
	=1 enable new 82439HX features
SeeAlso: #01099,#01108,#01098,#01112,#01111