Answering a Call

The technique to answer an incoming call is to set S0 - Ring After Which To Answer and wait for a CONNECT ___ result code. You may get several RING result codes, and possibly a NO CARRIER result code if the caller hangs up before connecting. These result codes should not cause your controller to abort. Continue to wait for a CONNECT result code.

If you set S0, you may want to return it to zero after your controller finishes the call to prevent inadvertent answering when your software is not running. By setting S0 to control the number of rings before the modem answers, you utilize the ring detection technology built into the modem.

You should not use the A command to answer after counting RING results because the command may conflict with another RING result from the modem and be missed. The RING results may be generated in pairs depending on the ringing cadence of the phone system.

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