Getting Started; Communicating With The Adm - AT&T 7506 User Manual

Getting Started

This chapter explains how to prepare your Asynchronous Data Module (ADM) for data
operations and how to make data calls.

Communicating With The ADM

You can ''talk'' to the ADM through an attached data terminal by means of commands typed
on the terminal's keyboard. There are two types of commands that can be used to talk to the
ADM: CMD and AT. CMD is the preferred method of talking to the ADM. However, if you
have a personal computer and you are using a communications package, you may need to use
AT commands because that may be the only command form the package understands. A
more detailed explanation of these commands can be found in Chapter 3, ''Using the CMD
and AT Commands.''
To use the commands, you must be communicating directly with the ADM in what is called
''local mode'' (Figure 2-1). In local mode, characters entered at the data terminal keyboard are
read, interpreted, and acted on by the ADM. This is in contrast to the ''data mode,'' in which the
ADM passes data from your terminal to your host computer or other data endpoint.
Data Mode
Local Mode
Data Terminal ISDN Telephone ISDN Network Host or Other
or Data Equipment
Personal Computer
FIGURE 2-1
Local and Data Mode Operation
Getting Started 2-1