Black Box MD1640A, MD1641A manual Dial-Up Operation 336+ Only, Manual Call Origination

CHAPTER 4: Manual Dial and Automatic Answer

4.6 Dial-Up Operation (336+ Only)

When your Series II Modem 336+ (MD1640A) is used as a dial-up modem (DIP-Switch #10 in the UP position), it can both originate and answer calls. To originate calls, you use the automatic dialing capability of the Modem's Command mode.

To do this, use the computer or terminal keyboard to enter a few command letters, followed by the phone number you wish to dial. If you have a computer with sophisticated communications software, you may end up talking back and forth with the software, and the software will take care of talking to the modem.

It is still possible, however, to dial your data calls using a telephone set. There are few reasons why you would want to do this, but if you have a need to use the telephone set to dial, we explain how in the next section. We will delay our coverage of Command Mode autodialing, and all other Command Mode features, until Chapter 5.

4.7 Manual Call Origination

You can use the Series II 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's PHONE 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.

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).

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