[Asterisk-Dev] Channel bank w/ bri card and Zaptel

[Steve Brown]

I have a t100p and Premisys bank w/ bri card. The bri card has 8 u ports 
that can be configured for either terminal or network. Each port uses 3 
ds0 channels, one for b1, b2 and d. The d channels of four ports can be 
multiplexed on the same ds0. Each of the 4 ports is assigned 2 bits in 
each ds0 byte. This seems pretty standard for other banks too.

Given zaptel support for the multiplexed d channel, it might not be too 
difficult to build a low-level hisax driver for zaptel and let 
isdn4linux do the L2/L3 stuff. I realize that i4l only does terminal 
(not network) protocol, but it's a start.

I've experimented with an isdn phone and nt-1. L1 syncs up and a dump of 
the d channel (configured as clear) shows the phone trying to establish 
L2 w/ switch. All the bits seem to be where they belong.

If you already have a channel bank, this seems like a tidy way to add isdn.

Has anybody familiar with zaptel and/or hisax looked into this?

Steve