[Asterisk-Users] Channel bank timing

[Andrew Kohlsmith]

On Sunday 25 December 2005 18:47, Rich Adamson wrote:
> I don't believe the above config is correct.

It should have been fine.

> Both channel banks will be generating timing/clock signals within their
> transmit leg towards the asterisk box. That is part of T1/E1 low level
> protocol design and you can't change it even if you wanted to.

Yes, but both channel banks can sync to the line, and the Sangoma card can be 
set to not sync to the line, thus becoming the master on both spans.

> On the asterisk T1 port connected to CB2, use:
>  span=2,2,0,esf,b8zs
> where the second "2" tells your asterisk T1 card to use this port for
> sync "if" the first port does dead, fails, cable is disconnected, or for
> any other reason that would essentially represent a failure of CB1.

There are two problems with this:  1. the A104 can have each span's sync 
independent of the others, unlike the Digium cards.  2. With both spans 
trying to sync to each other you can run into interesting clock situations 
you may want to avoid.

-A.