Bitfields for OPTi 82C750 Vendetta (device 1) emulation control:
Bit(s)	Description	)
 7	PCIRST# disable
 6	SDA2 muxed with XDIR	(0 = XDIR, 1 = SDA2)
 5	SPKR muxed with MIDI1	(0 = MIDI1, 1 = SPKR)
 4	audio mux		(0 = MP7-MP0, DACK)
 3	audio module enable
 2	ATA-33 IDE pin mux scheme (0 = old, 1 = new)
 1	REFRESH priority	(0 = high, 1 = lowest)
 0	port 92h emulation disable
SeeAlso: #00939,PORT 0092h