Re: HDLC via V.24 or b-channel?
Tilman Schmidt <[email protected]>
| Newsgroups | gmane.linux.isdn.i4l.user |
|---|---|
| Message-ID | <[email protected]> |
Am 15.03.2012 16:51, schrieb Jens Bürger: > I want to program an application for a PBX. The PBX is designed to be > connected to a PC and offers 2 interfaces for data exchange. [...] > The PC connects to the PBX via > - V.24, 9600 baud, asynchronous > or > - B-Channel > Additionally, connection schemes of installation instructions do note > "HDLC" between PC and the (V.24-)connection to the PBX. Upon re-reading this, I remember I saw something ressembling that description in a Siemens Gigaset M101 V.24 DECT adapter. That gadget would convert a regular bitstuffed HDLC datastream arriving over an ISDN B channel into byte-aligned so-called "asynchronous HDLC", where frames were enclosed in "HDLC flags" appearing as actual 0x7e bytes, and flag bytes appearing in the data were escaped with the PPP mechanism (XOR with 0x20 and prefix with the PPP escape character 0x7d). If you want to see an implementation, have a look at drivers/isdn/gigaset/asyncdata.c in the kernel source tree. Perhaps that's what your PBX does, too? HTH T. -- Tilman Schmidt E-Mail: [email protected] Bonn, Germany Diese Nachricht besteht zu 100% aus wiederverwerteten Bits. Ungeöffnet mindestens haltbar bis: (siehe Rückseite) _______________________________________________ isdn4linux mailing list [email protected] https://www.isdn4linux.de/mailman/listinfo/isdn4linux
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