AT&T 7400 series, 7500 series Standalone Data Modules, ADUs, Modems, Data Module Characteristics

8-6DTE CONNECTIONS

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Standalone Data Modules

Standalone data modules are self-contained pieces of equipment that transform the transmission signal as it enters and exits the switch. Standalone data modules include the following:

∙Modular Processor Data Module (MPDM) — A DCP data module that is used for both synchronous and asynchronous applications. It supports synchronous speeds up to 64 kbps; and asynchronous speeds up to 19.2 kbps. The MPDM can be provisioned with the ACCUNET modification kit. With this kit, the MPDM is called the MPDM/M1* or the ACCUNET MPDM.

∙Modular Trunk Data Module (MTDM) — A DCP data module that provides a DTE interface in modem pooling arrangements. It supports both synchronous and asynchronous speeds up to 19.2 kbps.

∙7400A — A DCP data module that offers both DTE and DCE interfaces. When it functions in the DCE mode, it provides break-signal and Hayes-AT dialing, and supports both terminal and host port connections. In the DTE mode, it functions in a modem pool through either the D-lead or Hayes AT command set. Its primary use is in modem pooling arrangements with analog modems.

∙7400B — A DCP data module that offers Hayes AT command set functions. Its primary use is in desk- top arrangements that need to support either standalone asynchronous terminal connectivity or connectivity for both a 74XX voice-terminal and a DTE. Note that the 7400B can only be reset through a terminal — no manual controls are provided. Therefore, it is not recommended for host applications.

∙7500B — A BRI data module that provides both a DTE and DCE interface. Without an associated voice terminal, the 7500B provides connectivity for a DTE with a switch BRI port.

∙3270C — A data module that converts DCP to coax-A protocol so that PCs that emulate 3270 terminals can access a 3270 cluster controller through the switch. The module is placed between the communications system port and the cluster controller.

ADUs

For connection to EIA ports, AT&T offers the following:

∙Asynchronous Data Unit (ADU) — A limited distance unit that can connect a DTE to an EIA port on a communications system or host. The ADU extends the DTE’s RS-232 interface over greater distances.

∙MADU — An 8-port ADU.

Modems

AT&T, Paradyne, and many other vendors, offer modems that can connect your DTEs to an analog port. Check the most current sales catalogues to find the modem that best meets your needs.

DATA MODULE CHARACTERISTICS

To determine which data modules are appropriate for your installation, you must match their characteristics with the characteristics of the DTEs you want to connect and the communications system ports you want to use.