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My voice modem education part 2

I need to clarify something that I think I've been way off base on.

I'm writing some VB.NET code to TRY and get my voice modem to play audio on a phone line after the call has been answered. (I posted a few days ago on this).

I can connect, dial out, pretty much do all of what I need to do and get an OK on all the steps when I talk to the modem.

Using, AT+VTX.... AT+VSM... AT+VLS and all that poop.

I was under the impression somehow that I could simply send raw analog audio into the modem from the sound card and get the job done......I mean after all, the modem has a MIC input and a LINE out audio jack....just like the sound card.

So, sound card out to modem in, right?

BUT, no matter what I try, no go.

So, I need confirmation (or not) on this......

When you are using commands like AT+VTX (to transmit audio), it has NOTHING to do with the modem audio jacks, right?

The modem itself processes a WAV file and puts it in the phone line itself?

After seeing the command AT+VSM, (audio data format selection) it sure seems this is the case?

THANKS.

Reply to
mkrnews
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Guess you were not paying attention to my earlier post!.

learn how to do sound card programming. The Voice Modem will show as a simple sound card in your system how ever, it may not show in the windows control panel as a suitable sound card for use in windows basic operations..

If you enumerate the audio devices using "WavEnumDevices" or something like that, you'll see the list of wave devices. Each device can be checked for it's capabilities and hardware attachments.

Normally, Voice modems are very low end units. The sample rate will be listed as low, along with bit rate also.

etc..

There are some voice modems that do not install them self's in the system this way, in which case, you would need to use vender supported DLL's or COM's to use it etc..

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Reply to
Jamie

Late at night, by candle light, snipped-for-privacy@gmail.com penned this immortal opus:

Something like it. I used to have a voice-modem doubling as an answering machine, and it had nothing to do with the sound-card. IIRC it went between the phone and the line, you had to speak into the phone to create the message, and it played any incoming messages to the phone. It did have an option to play messages through the sound-card, but outgoing messages had to be created by the software that came with it.

- YD.

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Reply to
YD

Ok.

Certainly, you understand my frustration.

My next step....

Just using the modem to call out and hardwiring a cap from the sound card's output to the front end of the modem's line interface.

Presto.

The world of modem programming is all over the place....the mere fact that it's either plus or hash makes universal programming impossible.

Reply to
mkr5000

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