asterisk users - Sep 2003 - using pci modem cards as fxs/fxo ports in *

Hi all,

forgive the question but is it possible to use PCI modem cards (aka
winmodem's) as FXO/FXS ports in * ?
what about external modems like the USR Sportsters?

Thanks in advance,
Bryan.

Bryan Nolen
Lead Developer
http://Arc.Net.AU
http://cdonline.com.au

Bryan Nolen wrote:
> forgive the question but is it possible to use PCI modem cards (aka
> winmodem's) as FXO/FXS ports in * ?
> what about external modems like the USR Sportsters?
Methinks this needs to go in an FAQ, and the FAQ needs to be linked to 
from the mailing list signup page/confirmation e-mails.

Long answer: Search the list archives/Google.

Short answer: Nope. Lack of voice duplexing tends to scupper you.

-- 
Alastair Maw <al.maw@mxtelecom.com>
MX Telecom - Systems Analyst
http://www.mxtelecom.com

On Wed, 17 Sep 2003 21:22:59 +1000, Bryan Nolen wrote
> Hi all,
> 
> forgive the question but is it possible to use PCI modem 
> cards (aka winmodem's) as FXO/FXS ports in * ? what about 
> external modems like the USR Sportsters?
short answer: no

disclaimer: somebody with better * experience, please review

long answer: there are two drivers for analog modems, chan_modem_aopen
and chan_modem_bestdata, which correspond to zyxel style voice
commands (AT+VRX &c.) and usr/zoltrix style (AT#VRX &c.). off the top
of my head, i can't remember which one is which but you can check it
easily in the sources.

with the two command sets mostly equivalent, the usr driver is
incomplete (i hacked it into supporting rates other than 8khz as my
zoltrix supports only 7200/11025 but it only rx'd audio. after a
stream of mysterious segfaults i gave up trying to hack it into tx'ing
audio too ;). i didn't have the chance to try the zyxel driver so i
can't comment. there's some code for audio tx in the zyxel driver, but
as i said, my attempts to copy the code to the usr driver failed
miserably. also i tried a conexant winmodem (yup, still using dialup
at home :(). under win98 at+fclass=? gives me 0,1,8 or the like
(0=data, 1=fax class 1, 8=voice) but under linux i only have 0. eh,
winmodems ;)

*however*, i remember a discussion here about one of the * gurus
planning to work on the modem drivers - will the brave individual
please stand up? :) i'll happily help as i'd be interested in the
driver too - haven't checked the development in the area for quite a
time though. if anybody is interested in my patches for supporting
audio rates other than 8khz (simplistic but acceptable quality sound
resample routines right in the driver - good or bad?), let me know,
i'll dig them up.
> 
> Thanks in advance,
> Bryan.
> 
> Bryan Nolen
> Lead Developer
> http://Arc.Net.AU
> http://cdonline.com.au
hth,
 grzegorz nosek