[Asterisk-Users] Sangoma E1 board Experience

[Rich Adamson]

> > Spec sheets are available for the TigerJet 320 pci chipset as well as
> > the Silcon Labs 3050, 3210 chip sets used on the TDM card. If you dig
> > through those I think you'll find that it would difficult if not impossible
> > to change the card's infrastructure since its based on the standards
> > noted above.
> 
> You're still not answering his question.  :-)
> 
> The TJ320 has no buffering capability but the Silabs parts have nothing to do 
> with that, and neither do the framers on the higher-density TDM cards.  I 
> think his question is more "why don't these cards have bigger PCM buffers and 
> interrupt less often, or at least have deeper buffers so if an interrupt is 
> delayed I don't get overruns?"
> 
> I believe the answer lies in latency.  You do *not* want deeper buffers.  
> Better interrupt handlers, perhaps, but not any deeper buffering on the 
> hardware, as that just increases latency.

I agree 100%. But, I don't believe any of that can be changed anyway on the
digium cards; I'm 90% sure the card's buffering (and therefore interrupt
frequency) is hardwired within the chip sets. (I've not tried to analyze the
T1/E1 cards, only the TDM card.)