need help finding voice modem

I need to find a basic rs232 voice modem for a proof of concept device. 
  The final product will have the functionality built in but for now I 
need an external solution.

The application will generate DTMF codes, and send a voice message.  The 
modem needs basic hayes commands, enough to go off hook and dial out, 
send a message and hang up or hold the line open.  ARM9 processor 
running a uLinux distro.

Any help would be appreciated.

Joe

Joe wrote:
> 
> I need to find a basic rs232 voice modem for a proof of concept
> device. The final product will have the functionality built in but
> for now I need an external solution.
> 
> The application will generate DTMF codes, and send a voice message. 
> The modem needs basic hayes commands, enough to go off hook and
> dial out, send a message and hang up or hold the line open.  ARM9
> processor running a uLinux distro.

You don't need a modem, just normal POTS service and at most a
relay to connect/disconnect.  Then it is your choice between DTMF
and pulse dialling.  

-- 
"The most amazing achievement of the computer software industry
 is its continuing cancellation of the steady and staggering
 gains made by the computer hardware industry..." - Petroski

> The application will generate DTMF codes, and send a voice message.  The 
> modem needs basic hayes commands, enough to go off hook and dial out, 
> send a message and hang up or hold the line open.  ARM9 processor 
> running a uLinux distro.

This is possible with the ZyXEL U1496E(+) series of modems.  However,
you will need quite a bit of time to get it to work, and even then it
wont be very reliable.  I would recommend you to not use a modem at all,
but rather a line-interface module (MITEL does some, IIRC MH44288 or so
is a product code to look for).  These convert the phone line into
audio-in and audio-out, plus control lines to pickup/hangup.  This line
interface, an ADC/DAC and off you go.  No Hayes, no char-pacing, no
CELP, no stuck sessions, no nothing.