I'm developing an application in Visual Basic 6 with the nokia 6630, does to be able to converse use the commands AT and AT+ work me except well almost all if I want to effect a vocal call, sending the command ATD<number> or ATD^<number> the call is always type data, which command do I have to send for effecting a call type voice? and to receive the DTMF tones?

You can make a voice by putting " ; " after the number.
( ATD1234; )
DTMF tones can be sent using +VTS command and ATD.
No knowledge of receiving.

To use ATD command for sending DTMF tones:
in case of voice call: originate call to the number preceding comma, wait for remote answer, pause for length specified with S8 register, and send numbers after comma as DTMF digits; further commas cause pause for length specified with S8 register (all commas are ignored in case of data call)

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