[Asterisk-Dev] Strange situation with two Digium E100Ps..

[Peter Svensson]

On Thu, 9 Sep 2004 cf at internetit.dk wrote:

> Hi Guys,
> 
> I have this strange issue with two single E1 cards (E100P), apparrently when having a zaptel.conf looking like the following (which should be correct according to the instructions found everywhere)
> 
> span=1,1,0,ccs,hdb3,crc4
> bchan=1-15
> bchan=17-31
> dchan=16
> 
> span=2,2,0,ccs,hdb3,crc4
> bchan=32-46
> bchan=48-62
> dchan=47

[snip]
 
> When changing to:
> 
> span=1,1,0,ccs,hdb3,crc4
> bchan=1-15
> bchan=17-31
> dchan=16
> 
> span=2,1,0,ccs,hdb3,crc4
> bchan=32-46
> bchan=48-62
> dchan=47
> 
> The error goes away and all channels are functional.. But according to info regarding zaptel.conf this means that you use both cards as timing source?!
> It doesn't seems to have any effect on the system, but still a little strange.

The timing is only per card and cannot be carried between cards. One 
channel on each card needs to be the timing source. For the E100P the 
timing source should either be 1 (external timing) or 0 (the E100P is the 
clock source). 

For some setups it would have been advantageous to be able to derive the 
timing of one card from another. I do not know if it is even possible 
using the hardware on the E100P/TE405P cards. I guess some form of pll in 
software could be used. I don't think it exists yet. There was some 
discussion a month ago or so.

Peter