Multitech MT2834BAI, MT1432BA manual Manual Call Origination, Automatic Answering

Chapter 4 - Manual Dial and Automatic Answer

4.3Manual Call Origination

You can use the modem to both originate and answer calls. To originate calls in Asynchronous mode, you will most likely use the modem's Command mode, and give the modem automatic dialing commands (we will delay our discussion of the Command mode until Chapter 5). When using your modem in Synchronous mode, the Command mode is disabled, so you must automatically dial your calls with a telephone set. To use manual dialing, you first connect an ordinary telephone set (either touch tone or rotary dial) to the modem'sPHONE Jack, if you have not already done so. Next, set the speed selection, (DIP-Switches #13 and #14), to the speed at which you wish to communicate. These DIP-Switches are located on the side of the modem. (Refer to Chapter 9 for DIP-Switch settings.) Your computer or terminal may be set for up to 115,200 bps (57,600 bps for 1432 models, 37,800 bps for 932 models).

When your telephone set is connected, you can use it to dial the modem you wish to call. Simply dial the number, and then listen to the dialed modem's answer tone. When you hear it, press the Voice/ Data switch on the front of the modem down (to the Originate position). You don't have to hold it down. Just "toggle it" (press it once and let it go). Once you press the switch, the tone you hear should change to another pitch, or change into a rough-sounding scrambled noise. You then replace the telephone handset in its cradle, and your data communications begins.

Note that the modem may call manually via the keyboard command ATD, or by pressing the Voice/ Data switch on the modem's front panel downward. To force the modem to automatically answer calls, either type ATA, or press the Voice/Data switch on the modem's front panel upward.

4.4Automatic Answering

The modem can be used as an automatic answering modem. No special modifications or settings are required other than making sure that the Auto-Answer select switch is set to Auto-answer enabled (DIP-Switch #5 UP).

The modem, when in its idle state, is set for Originate mode frequencies. An incoming ring signal automatically switches the modem into Answer mode.

You can program the modem to answer a call after a certain number of rings using S-Register S0 (see Chapter 6). Refer to Section 4.10 for the handshaking procedures used by the modem when in automatic answer mode.

In many originate-only applications, you may wish to disable the automatic answer capability of the modem. If a telephone set is connected to the modem, you may wish to receive incoming calls in a voice mode for normal voice conversation. If auto-answer is not disabled, all incoming calls are answered by the modem, preventing voice communications. To disable automatic answer, place DIP- Switch #5 to the DOWN (Disable Auto Answer) position (refer to Chapter 9).

Another way to disable automatic answer is to use S-Register S0 to configure the modem to answer on the nth ring, where n equals zero (0). Another alternative is to have the modem answer after five or six rings, which gives you time to answer it manually if you wish. (See Chapter 6 for S-Register information.)

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