On Sun, Jan 25, 2004 at 12:08:00AM +0100, Wojciech Puchar wrote:
> i heard it is possible having 2 ISDN cards in machine and having special
> wiring so one card has TX and RX pair reversed (so both directions can be
> recorded)

See isdntrace(8) and look for -a and -b. It refers to cable.txt for the wiring,
which you will find in src/usr.sbin/isdn/isdntrace. (This is arguably a bug,
maybe cable.txt should be installed to share/doc or something)

Martin