[Asterisk-Users] two isdn cards

[Stankiewicz Michael]

thanks a lot,
i've googled around hunting for an answer to my biggest doubt: the
cross-cable.
i understand that it looks like an cat-5 cross-cable and how it has to
be done, but ... why 8 wires ? 
i found this image: http://www.gcom.com/home/support/t1crossover.html
and that one:
http://www.voip-info.org/wiki-crossover+T1+cable?page=crossover%20T1%20cable&comments_threshold=0&comments_offset=0&comments_sort_mode=commentDate_desc
...
so: the cable that goes from the isdn NT to asterisk should be an 8
wires isdn-cross-cable ?

thanks for those newbye delightenments :)
ciao
mike


On Mon, 2005-05-23 at 16:50, Emanuele Pucciarelli wrote:
> Stankiewicz Michael wrote:
> 
> > i followed this how-to:
> > http://www.voip-info.org/tiki-index.php?page=Asterisk%20zaphfc%20install26
> > having in response no sign of life.
> 
> If the module doesn't even get installed, or the kernel does not report
> any card as recognized, you could tweak the initialization routines to
> add PCI IDs for your own cards, and hope they work correctly.  If the
> cards are recognized, there should be nothing to worry about: either
> they work with zaphfc or they don't, modulo interrupt troubles.
> 
> > the software side is pretty straightforward but i have many doubts on
> > the hardware deployment:
> > 1- the idsn cable going from asterisk to the NT sould be a cross cable ?
> 
> Yes.  But not an Ethernet cross-cable, an ISDN cross-cable; there's a
> pointer on the wiki to a page on isdn.jolly.de explaning how the cable
> should be made, and suggestions about how to take advantage of a disused
> NT.  I reckon that telephony folks call it an "ISDN TX/RX" cable.
> 
> > 2- it should have 100 ohm resistors (if yes, where can i find the
> > schemes )?
> 
> Yes, the bus should be terminated (so the resistors don't have to be on
> the cable itself).  A full description of the bus is in the ETSI
> standard for ISDN layer 1 (www.etsi.org).