MultiModemISDN User Guide

accepts any incoming call with the same base address, regardless of whether a subaddress is included. If you assign a base address and a subaddress to the MSN, the unit only accepts calls that match both the base address and the subaddress. The following examples show the syntax for setting the MSN with and without a subaddress. AT command: !N1=

MSN with subaddress: AT!N1=5551000:001 (base address is 5551000; subaddress is 001)

MSN without subaddress: AT!N1=5551000 (base address is 5551000)

Voice MSN __________________________________

Selects calls on the voice channel in the same way the Data MSN selects calls on the data channel. AT command: *!N1=

SPIDs and DNs ______________________________

For use with North American switches, the Service Profile Identifier (SPID) must be configured in the MTA128ST-USB. The SPID is assigned by the local phone company and is for the specific BRI line where the unit is attached. The SPID field is empty prior to configuration.

AT commands: AT!C6= and AT*!C6=

Directory Number (DN) is the phone number another user calls to contact this unit once it is attached to the ISDN.

AT commands: AT!N1= and AT*!N1=

Note: SPIDs and DNs are used only by the U.S. NI-1, AT&T 5ESS, and DMS-100 switch types.

Call Control Configuration

Persistent DTR Dialing _______________________

A high DTR (Data Terminal Ready) signal on the USB port indicates your computer or terminal is ready to communicate with your MTA128ST-USB. DTR normally goes high when a communication program starts or is ready to dial. Persistent DTR dialing enables the unit to automatically redial the number stored in memory location 0 whenever DTR is high and the serial port does not have an active call. You can enable or disable this feature. AT command: $D

Auto Answer Data Calls __________Rings to Answer ___________

Select Auto Answer if you want your MTA128ST-USB to automatically answer all incoming data calls (this option does not affect the analog port). The Rings to Answer number, in the range of 1 to 255, selects the number of rings the unit waits before answering an incoming call. The default is one ring. AT command: S0=

Dialing Method _____________________________

Select either the Enbloc or the Overlap dialing method for use when establishing a data call.Your ISDN provider determines the dialing method. The Enbloc method is used for most ISDN dialing; however, you can select the overlap method if you are working with a private network. AT command:

%A97=

Data Protocol ________________________________

The data protocol, also known as the B-channel protocol and the rate adaption protocol, is the language spoken over each 64 Kbps channel between two ISDN devices. The devices on both ends of the ISDN link must use identical protocols. AT command: !Z=

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