Multi-Tech Systems DT101/xx, DT102/xx Configuration 2 - MMH900 Series with Voice/Fax

Chapter 2 - Configuration

2.3 Configuration 2 - MMH900 Series with Voice/Fax

Configuration 2 adds voice capability to an existing data-only network using the same composite link. The example shown in Figure 2-2 had an existing data-only network consisting of a MultiMux MMH904C multiplexer connected to a host computer at the local site and a second MMH904C connected to terminals and/or PCs and a shared printer at the remote site. To add voice capability, a DataTalker is added between the composite link of the MMH904 and the public data network (PDN) at both sites. The composite link between the two sites is now moved from the MMH904 multiplexer to the new DataTalker. The composite link of the MultiMux MMH904 is reconfigured as an external synchronous link device and connected to the synchronous data channel of the DataTalker. The voice capability is added by connecting a telephone to the FXS port on the back panel of the DataTalker at each site and configuring the voice/fax channel of the DataTalkers for FXS to FXS. Now, while you are transferring data over the composite link, you can pick up the telephone and have a simultaneous voice conversation.

Asynchronous	Sync Data	Sync Data	Asynchronous
Channel	Channel	Channel	Channel
	Composite Link
MultiMux MMH904	PDN	MultiMux MMH904
Voice/Fax	DataTalker		Voice/Fax
Channel
	DataTalker		Channel
Telephone		Telephone
Local Site			Printer

Remote Site

Figure 2-2. Adding Voice to Data-Only Network

The async channels of the MultiMux MMH904s operate the same way as in the data-only network. The MMH904 is reconfigured for an external link device by changing the 8-position DIP switch position 2 to the down (closed) position, ensuring that the composite link is configured for sync mode, and setting clocking to External. An RS232C cable can now be connected to the COMPOSITE LINK EXTERNAL RS232C/V.35 connector on the back panel of the MMH904.

The composite link connection of the DataTalker to the PDN depends on the type of link device being used. If the link device is an internal 33.6K bps modem, connect the Modem DIAL-UP or LEASED connector to the PDN. If the link device is an internal DSU or ISDN terminal adapter, connect the DSU/TA DIGITAL connector to the PDN. If an external link device is used, cable it to the EXTERNAL COMPOSITE RS232C/V.35 connector. The connection type depends on whether the interface of the external link device is RS232C or V.35. If it is V.35, a shunt on the main board of the DataTalker must be moved to the V.35 position.

You must configure the DataTalker before you connect it to the MultiMux MMH904. To configure the DataTalker, place DIP switch position 3 in the down (closed) position and connect a command port device such as a terminal or a PC to the DATA/COMMAND connector on the back of the DataTalker. Turn on the DataTalker and PC and run your communications software in terminal mode. (Set it for direct connection at a serial port speed of 19,200 bps or slower.) Press the ENTER key to establish communications with DataTalker and see the Main Menu.

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