Bitfields for CAPI v2.0 B2 protocol support:
Bit(s)	Description	)
 0	ISO 7776 (X.75 SLP) (required, always set)
 1	transparent
 2	SDLC
 3	Q.921 LAPD (D-channel X.25)
 4	T.30 for group 3 FAX
 5	point-to-point protocol (PPP)
 6	transparent (ignoring B1 framing errors)
 7-31	reserved (0)
SeeAlso: #04074