Good afternoon,

I have a PcTel HSP56 Mr Data/Fax/Voice/Speakerphone modem. I am
writing a program to answer the phone in my absence.

I am playing VOX files compressed in Rockwell ADPCM at 7200K 4bit. My
first question is: when I send the modem an At#Vtx command, I can
submit the Vox file in 2400-bite chunks and the modem starts playing
the data. It, however, never sends a message back asking for more
data, so I simply wait a tenth of a second and send the next block.
This sort of works, but the audio often varries in volume and music,
for some reason, increases drasticly in volume and sounds aweful.

Second: I cannot record audio from the modem. When I send an At#Vrx
command, the modem responds with Connect, then sends <Dle><Can>
indicating the audio transmition is finished, and returns to vCon
(online voice command mode.)

So my questions are thus:

1. How should I properly submit the VOX data to the modem?

and 2. How can I receive Vox data from it?

As a sideline, if you find a freeware command-line utility or DLL to
convert Vox to Wave and vise-versa, I will be delighted to pay an
extra ten dollars.

Thank you for your time and the excellent service you researchers
provide. I know it's going to be a pleasure working with you. - Craig.

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Request for Question Clarification by aht-ga on 29 Sep 2003 16:31 PDT

marvelsoft-ga:

I see that you are still hackin' away at that program! Based on the
work we both put into your last question about programming this modem,
I will see if I can find any additional resources to help you.

Regards,

aht-ga

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Request for Question Clarification by aht-ga on 29 Sep 2003 16:49 PDT

marvelsoft-ga:

For the second part of your question, regarding recording: have you
already confirmed that after the AT#VRX<CR>, no other characters are
being sent from the DTE to the modem? Also, have you explicitly set
S30 to a non-zero value?

There are supposed to be only two ways to cancel recording; one is
through the expiry of the S30 timer value, and the other is through
"any key press", ie. any character being transmitted from the DTE to
the modem.

Regards,

aht-ga

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Request for Question Clarification by aht-ga on 29 Sep 2003 16:59 PDT

One last clarification request before I stop and wait for your
responses...

Since it has been a while since your last question, can you please
tell me what communications settings you are now using between the DTE
and the modem? The AT#VTX flow control is managed through XON/XOFF
(ie. software flow control), so it is up to the program to calculate
(based on querying the buffer size, and the sample rate of the sound
data) the amount of time to pause before transmitting again if an XON
is not received.

So are you getting the XOFF from the modem?

Thanks,

aht-ga

It is not clear what you are trying to accomplish.

marvelsoft-ga,

An alternative is to buy a conventional answering machine for $12 at
Best Buy, or perhaps sign up for voice-mail with your local telephone
provider. What is the advantage of this complex computing method of
phone call recording?

Commerically available programs such as "Soft Call Recorder" record
large volumes of calls with the time/date stamp and number into a
database for later retrieval (in case the client disputes ever making
a reservation, for example). Is this along the lines of what you are
trying to accomplish?

omniscientbeing-ga
Google Answers Researcher

Craig,

Another alternative program is TalkWorks PRO.
http://www.geek.com/hwswrev/software/talkworks/talkworks3.htm

-Feilong

See also asterisk.org. Free open-source PBX, VoIP capable, voicemail built in.