Nothing to odd - the PM-3 has a digital switch. When the data comes in
as voice on a PRI, or anything on a ChanT1, it is sent to a DSP as well as
the HDLC controller. HDLC will always sync first if it is really a DOSBS
call. If it does the HDLC controller tells the DSP to give up. If it
doesn't the DSP is allowed to continue trying modem negotiation.
>I have a question here too. I have Black's _ISDN and SS7_ book, and from
>what I've seen, there is no mention of a field in either layer 2 or 3 that
>distinguishes an ISDN voice call from an ISDN data call. Can somebody
>tell me how the two are distinguishable?
D channel signalling.
-MZ
-- Livingston Enterprises - Chair, Department of Interstitial Affairs Phone: 800-458-9966 510-737-2100 FAX: 510-737-2110 megazone@livingston.com For support requests: support@livingston.com <http://www.livingston.com/> Snail mail: 4464 Willow Road, Pleasanton, CA 94588