Telephone modules - IP telephone, ISDN, PBX

We are looking for ready-made telephone modules that can connect to an 
ISDN or IP-telephone PBX.  They should have some sort of control 
interface (typically UART) for dialing, hang-up, ring, etc., and 
analogue audio in and out.

/Long/ ago, I used an analogue modem module like this.  I also had an 
ISDN modem module, but it didn't support audio in and out - it was only 
for data.  And of course they are now out of production anyway.

Ideally we would like one supplier that can provide both kinds of 
modules, so that we can easily swap them out depending on which version 
the end-user needs.  But at the moment, we are interested anything we 
can find.

Our customer has a very short schedule here, so we want to find 
something ready-made - and I'd like to avoid learning about IP telephony 
if I can!

mvh.,

David

In article <joednTtIj9xj7m3QnZ2dnUVZ8hadnZ2d@lyse.net>, 
david@westcontrol.removethisbit.com says...
> 
> We are looking for ready-made telephone modules that can connect to an 
> ISDN or IP-telephone PBX.  They should have some sort of control 
> interface (typically UART) for dialing, hang-up, ring, etc., and 
> analogue audio in and out.
> 
> /Long/ ago, I used an analogue modem module like this.  I also had an 
> ISDN modem module, but it didn't support audio in and out - it was only 
> for data.  And of course they are now out of production anyway.
> 
> Ideally we would like one supplier that can provide both kinds of 
> modules, so that we can easily swap them out depending on which version 
> the end-user needs.  But at the moment, we are interested anything we 
> can find.
> 
> Our customer has a very short schedule here, so we want to find 
> something ready-made - and I'd like to avoid learning about IP telephony 
> if I can!
> 
> mvh.,
> 
> David

There are numerous products that connect analog PSTN type telephones to 
ISDN lines. Typical products allow two analog phones to connect to one 
BRI connection. Some of these are easily configured using DTMF commands 
that would normally come from the attached phone. You could provide 
support for that using an older style modem to synthesize DTMF signaling 
onto the 
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nalog phone pair. You could use the attached phone set to do the 
conversion from the 2-wire to 4-wire analog by interfacing at the 
handset jack. 

-- 

Michael Karas
Carousel Design Solutions
http://www.carousel-design.com