[Asterisk-Users] Voice Modem + Soundcard Driver

[Anthony Wood]

The problem with using Voice Modems is that they fall into two categories:

1) Hardware Modems which only have half-duplex transmission of voice
2) Soft/Win/Lin modems which are proprietry and don't have asterisk drivers

Please shoot down this recipe before I waste any time trying to acheive it:

Rationalisation:
----------------

In Australia and I assume other places, there is no
asterisk-compatible low-end hardware which is legal to use.
This could be a way to use existing certified hardware
with asterisk.

Ingredients:
------------

2 Phone lines
2 Banksia Wave SP 336 Modems - these have 3.5mm female jacks for speaker/microphone
1 Full Duplex Soundcard
4 3.5mm mono male-male audio cables
2 3.5mm stereo male -> 3.5mm female left + 3.5mm female right adapters
1 Linux Box with 2 serial ports and spare PCI slot for Full Duplex sound card.
Asterisk
Programmer

Method:
-------

Plug modems into phone lines and serial ports as per normal
Plug adapters into lineout and linein of sound card 
Plug modem 1 speaker into left of soundcard linein adapter
Plug modem 2 speaker into right of soundcard linein adapter
Plug modem 1 mic into left of soundcard lineout adapter
Plug modem 2 mic into right of soundcard lineout adapter

Adapt soundcard driver and/or other drivers to:

initialise modems to use Caller-ID via the serial lines
expect RING and caller_id info from the serial lines
send AT commands to answer calls, end calls, originate calls
get voice data for lines 1&2 from left & right channels of soundcard line in
send voice data for lines 1&2 to left & right channels of soundcard line out

Diagram:
--------

POTS-----------------------------------------Line 2
 |                                             |
Line 1                                         |
 |                                             |
Line                                         Line
---------                                   ----------
|        =mic-------------\   /----------mic=        |                       
| Modem1 |                |   |             | Modem2 |
|________=spkr--\   /-----|---|---------spkr=________|
                |   |     |   |
                |   |     |   |
                L---R     L---R
                |   |     |   |
                \   /     \   /
                 \ /       \ /
                  |         |
           |---Line In---Line Out---|
           |                        |
           |       Sound Card       |
           |------------------------|

Am I out of my tree?

Comments, flames?

cheers,
-- 
Woody