HOWTO: Using BRICONF to configure a Brooktrout TR114 BRI intelligent fax card.

ID: ZTN1049

This Zetafax technical note applies to:

• Zetafax 5.5 up to Zetafax 2008.

Summary

BRICONF is a Brooktrout utility program that is primarily used to configure the TR114 ISDN daughter card when you cannot use the default datalink (point-to-multipoint) or bearer capability (3.1k Audio).

Other BRICONF functions available are:

• Download of updated BRI firmware
• Protocol analysis of the ISDN daughter card
• Initialization of the ISDN daughter card

This document gives details about the differences between point-to-point and point-to-multipoint datalink configurations, and instructions about how to use the BRICONF program to change these settings.

More information

One ISDN interface is required for every two fax channels. A single standard basic rate line provides two channels called bearer (or B) channels, which can be used simultaneously, for both incoming and outgoing calls. Call control for both of these channels is provided over a single, shared D channel. These three channels are multiplexed together onto 4-wires providing the so called 2B+D Basic Access. These 4 wires terminate in a single RJ45 (EN 28877) connector, referred to as the S/T ISDN interface.

The most important variable in an ISDN installation is the protocol used for establishing a datalink between a piece of TE (Terminal Equipment) and an NT (Network Termination). There are two types of connection, point-to-point and point-to-multipoint.

The user rarely has a choice over the type of datalink.

Point-to-point

This datalink is intended to connect a single piece of TE (such as a TR114) to a NT. The ID which is referred to as the TEI (Terminal Endpoint Identifier), is used to identify or address all data packets and is fixed - usually to Zero.

Point-to-multipoint

This datalink is intended to connect multiple TEs to a single NT. Up to 8 devices can physically be connected to the same ISDN bus. Any of the connected TEs can be given a free B channel to place a call. Incoming calls are broadcast to all connected TEs, and often the TE is programmed to answer only calls destined to a specific number, by specifying a local address.

The ID, or TEI cannot be fixed at zero (as in point-to-point), because multiple TEs need to be addressed. All TEs on the ISDN bus are expected to participate in automatic TEI procedures in order to request a TEI (or address) from the network, before a datalink can be established.

When placing a call, a TE presents certain characteristics of itself in order to request a certain bearer capability of the network, and to allow a receiving device to establish if it is compatible with the sender before answering the call. Two important bearer capabilities are speech and 3.1k audio. Speech specifies the lowest level of service, and is the bearer capability used by telephones. 3.1k Audio is the bearer capability recommended by the appropriate standards for fax group 2/3. 3.1k Audio ensures a higher quality of line than guaranteed by speech. Some public and private networks do not correctly handle bearer capabilities set to 3.1k Audio, and may reject the call.

If any of the above variables apply to your installation it is necessary to edit the user-defined configuration file (BRI.CNF) which consists of lines of keywords. When invoked, BRICONF reads BRI.CNF and sets parameters within semi-permanent flash memory on the TR114 ISDN daughter card. These parameters define certain characteristics of the ISDN protocol and remain on the board even when power is removed.

The procedure for configuring the ISDN daughter card:

1. Edit the IRQ and I/O in BTDRIVER.CNF on the Brooktrout diagnostics diskette to match those on your card.
2. Edit BRI.CNF to match the ISDN network.
3. Boot the PC using a DOS boot diskette.
4. Load Brooktrout driver using the command line :

btdriver btdriver.cnf

5. Program using briconf using the command line:

briconf [{-p bri.cnf}{-f filename}-d{c|e}]

If the program is invoked with no arguments, it initializes the ISDN daughter card. However, the card is automatically initialized so you should not have to initialize it.

You can use BRICONF to download updated firmware to the ISDN daughter card. For example, to download the firmware from the file tr114.s, type:

                      briconf -f tr114.s

Bri.cnf

The user-defined configuration file, bri.cnf, consists of lines of keywords. On each line, optional information can precede the keyword. This optional information makes the keyword apply to a specific card, D channel, or TR114 channel. Each line has the following format:

[{card_number|card_address}[d_chan[d_tr114_chan]]]
keyword params...

Note that the TR114 channel that uses the D channel can have a value of 1 or 2 unlike the normal numbering of the TR114 channel that has a range of 0 - (N-1), where N is the number of channels. Each D channel corresponds to two B channels. These are used by two TR114 channels, but with no fixed correspondence between the B channels and the TR114 channels. If you have TR114 channels 0 - 3, specifying d_chan 1 and d_tr114_chan 1 means the first of the two TR114 channels using D channel 1, which is TR114 channel 0. D_chan 1 and tr114_chan 2 means TR114 channel 2; d_chan 2 and tr114_chan 1 means TR114 channel 2; and d_chan 2 and tr114_chan 2 means TR114 channel 3.

If you do not include any of the optional information, the keyword applies to all cards, both D channels, and both TR114 channels (if applicable) using each D channel.

If you begin a line with #, the line is ignored.

The keywords and their parameters are as follows.

Last updated: 01/06/09 (GC/MW)