The V.92 Quick Connect feature is controlled by the +PSS and +PQC commands. The +PQC command enables and disables the shorten phase 1 and or phase 2 startup procedures. The +PSS command forces either a short or full startup procedure on the next and subsequent connections. To enable the modem for V.92 Quick Connect, set +PSS=0 or 1 and +PQC=0. Refer to Table 3-4. for the detailed description of these commands.
The Modem-on-Hold (MOH) feature allows you to receive an incoming voice call and stay connected to the Internet and then return online after your conversation without having to redial. This is very convenient where the same phone line is used for voice calls and data connections. To receive an incoming call as described above requires that you have the Call-Waiting service from your telephone company. In addition, the Caller ID service from your telephone company is recommended but not required for MOH. This feature allows you to determine who is calling. The "hold" time for your incoming call is define by your service provide. The MOH feature also allows you put you data connection on hold and initiate a voice call and then return online after completing your voice conversation. These two scenarios are described in detail in the modem-on- hold flow charts.
The following sequence describes how to configure the modem for MOH to process an incoming voice call while online. First, MOH must be enabled. The +PMH and +PCW commands are used to enable MOH and to capture the Call Waiting tone which is sent when the voice call comes in. To enable MOH, set +PMH=0 and +PCW=0. Next, to enable Caller ID information (optional), by setting +VCID=1. Now the modem is configured for the incoming call. When you receive the incoming call, the modem will get a ring indication and the software/application will issue a
+++AT to put the modem in command mode. Then, you will be prompted to either "Accept" or "Reject" the call based on the Caller ID information (if enabled). If you reject the call, an ATO command is issued to perform a Quick Connect to stay online. If you accept the call, the data connection is put on hold, and the modem send ad request to the server to go on hold using the +PMHR command. The server will accept enable (1-13 returned) or reject(0 returned) the request. If the server accepts the request to go on hold, the modem issues the +PMHF to flash the hook to connect the call. Now you can answer the phone and talk. After completing your voice conversation, the modem will issue another +PMHF and ATO command to initiate a Quick Connect. If the server rejects the request to go on hold, the user can stay on line (ATO command issued) or disconnect from his initial data connection (ATH command issued).
The next sequence describes how to initiate a voice call while online. First, enable the MOH feature by setting +PMH=0. When online, the user can initiate a voice call by first issuing +++AT
to put the modem in command mode. Then request the server to go on hold by issuing the +PMHR command. The server will either accept (1-13 returned) or reject(0 returned) the request. If the server accepts the request to go on hold, the modem issues the +PMHF to flash the hook and get dial tone. You can then make a voice call. After completing the voice conversation, the modem will issue another +PMHF and ATO command to initiate a Quick Connect. If the server rejects the request to go on hold, the user can stay on line (ATO command issued) or disconnect from his initial data connection (ATH command issued). Refer to Table 3-4for the detailed description of the V.92 commands.
The PCM Upstream feature allows you to upload data to the network up to 48,000 bps. This is an improvement over the 33,600 bps maximum with V.90. This is beneficial when you are sending large file, e-mail attachments and gaming on the Internet. The +PIG command is used to enable and disable the PCM Upstream feature. To enable PCM Upstream, set +PIG=0. To disable PCM Upstream, set +PIG=1.
Several V.34 modes are available (see Table 3-2). These provide different speeds. For example, V34B offers a modem-to-modem data rate of 2400, 4800, 7200, 9600, 12,000, 14,400, 16,800, 19,200, 21,600, 24,000, 26,400, 28,800, 31,200, and 33,600 bps. For V.42, MNP, and Buffer (Normal) modes, the modem provides speed buffering (see Chapter 4 starting on page 63), which
