[Asterisk-Users] FXS Disconnect Supervision (Kewlstart / OpenLoop Disconnect)

[Andrew Kohlsmith]

Why'd your mailing software fake your From: to be my email address?

On Monday 31 October 2005 09:35, akohlsmith-asterisk at benshaw.com wrote:
> I started with a Voicetronix Openswitch12, which has, even in its driver
> code, no support for anything resembling kewlstart.  After figuring out
> that the MICS seemed to respond to opening the circuit for a short time, I
> tried to program a "flash" into asterisk (and then tried to write simpler
> code to interface with their driver) and found that doing anything with
> flash or "on/off hook" status while the card was in FXS mode made the port
> totally unstable.  I've been dealing with someone at Voicetronix and, after

Well generally speaking you can't do a damn thing with a channel once a hangup 
is done.  

> After my boss caught wind of it, he's now trying to control the situation a
> bit.  We ordered a Digium card AND now he wants to create a circuit with as
> many relays as we have lines and trigger that using signals from the
> parallel port.  I'm extremely hesitant to go that route for obvious
> reasons. I'm hoping the Digium card works, but if it doesn't, I'm stuck
> either returning a lot of hardware or going to get solder burns.

hahaha yeah that's a direct way to do it but very hackish for sure.

First things first.  With a voltmeter across tip-ring, what do you see when 
Asterisk hangs up?  The port should be in fxo_ks signaling, of course.  You 
may also want to meter out the wctdm_ioctl() function to make sure that the 
POLARITYREVERSAL IOCTL's getting hit.  

I read some more on that original URL you posted, I imagine that the wctdm 
driver drops battery for POLARITYREVERSAL in FCC mode, but you can verify 
this too.  It *shouldn't* be too difficult to change the function of that 
IOCTL, wctdm is actually pretty nicely documented, and the datasheets for the 
SLIC are available.

-A.