[Asterisk-Dev] A few driver ideas...

[James Harper]

> > 1. zaptel wrapper for mISDN. Would this add any value to anyone?
I've
> > had a look around in the code for both drivers and it doesn't seem
too
> > impossible...
> 
> What should that look like and what should it do? mISDN handles the
> complete protocol stack in the kernel but zaptel is just a stupid
layer 1
> device...

Ah. That makes some sense. So where is the protocol stack handled if
zaptel is doing layer 1? Userspace?

> > 1a. A hypothetical question. ISDN adapter A has a perfectly
functional
> > mISDN (and therefore CAPI) driver available for it. ISDN adapter B
has a
> > perfectly functional zaptel driver available for it. Both adapters
are
> > reasonably priced and are functionally identical. For use under
> > Asterisk, which would you prefer?
> 
> Well, zaptel ISDN drivers (as in BRIstuff) have the advantage of
> delivering a timing source to asterisk. But they also reduce latency a
lot
> when you are bridging from an ISDN BRI card to another zaptel device
(may
> that be a PRI card or some FXS/FXO thingies...) because it is bridged
> inside the kernel. Also debugging signalling problems in userspace is
much
> quicker than in kernelspace.
> An additional benefit would be that you get layer 1,2,3 certified
(TR3,
> TRB3-A1) drivers (and protocol stack) with our zaptel approach.

So if you have some existing zaptel stuff, a zaptel driver based card
would definitely be the better option?

> > 3. zaptel driver for the 'netjet' PCI BRI adapter (one of the few
> > available in Australia, and by far the cheapest). There is an
mISDN/CAPI
> > driver for it now, but it is a bit unreliable for me at the moment.
> > Maybe my time would be better spent fixing bugs in that...
> 
> Can you tell me which chipset they are using? I already have some
> winbondish card laying on my desk that is waiting for a zaptel driver
> (unfortunately it only supports TE mode but the chipset is suitable
for a
> good zaptel driver compared to the HFC-S PCI A chipset).

It's supported by the hisax driver and users the 'Tigerjet320' PCI
chipset and a Siemens ISAC. If that doesn't help I can probably find out
more...

James