AT&T System 85 manual Z702AL1 Data Service Unit DSU

Digital Terminal Data Module (DTDM)

Z702AL1 Data Service Unit (DSU)

The Z702AL1 DSU, when connected to the 7407D01B voice terminal, allows the user to transmit and receive voice and data over the same standard two pair of wires. The DSU provides the RS-232-C connection the data terminal needs to communicate with other data equipment without separate lines or modems. (See Figure 2 below.) The DSU supports asynchronous, full duplex operation.

FIGURE 5-2. Block Diagram of Z702AL1 Data Service Unit Interfaces

Applications

The Z702AL1 DSU can be used with a 7407D01B voice terminal connected to a DEFINITY G1, G2, or G3 system, System 75, and System 85. Typical applications are users with data terminals requiring a large number of features and lines.

Features

The Z702AL1 DSU provides the following features:

Selector for standard data rates of 0.3, 1.2, 2.4, 4.8, 9.6, and 19.2 kbps

Asynchronous full duplex operation

Automatic data call answering

Data terminal keyboard dialing

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