# Changing configuration parameter settings

When you run oamsys, the utility starts all boards according to the configuration parameters specified in their associated board keyword files.

To change a parameter:

- Use or modify one of the sample board keyword files corresponding to your country and board type. Specify the name of this new file in the File statement in oamsys.cfg and run oamsys again. Refer to the NMS OAM System User's Manual for information about the syntax of board keyword files.

- Specify parameter settings with oamcfg. Refer to the NMS OAM System User's Manual for information about oamcfg.

- Create a new board keyword file, either with additional keywords or with keywords whose values override earlier settings.

- Specify the settings using the OAM service functions. Refer to the NMS OAM Service Developer's Reference Manual for more information.

You can use oamsys to:

- Change which software module files are downloaded to the board at startup. Refer to Specifying configuration file locations for more information.

- Specify board switching.

- Configure CT bus clocking.

## .leo files

A .leo (loadable extensible object) file is a run module, a modular extension to the core file. The core file and the run modules make up the software that runs on the board's coprocessor.

The following .leo files are included with AG 2000-BRI:

File | Description
--- | ---
svc.leo | DSP function manager.
gtp.leo | Trunk protocol engine.
voice.leo | Play and record manager.
brietsi.leo | ISDN protocol (ETSI variant).
brivn6.leo | ISDN protocol (France Telecom VN6 variant).
brintt.leo | ISDN protocol (Nippon Telegraph Telephone INS-1500 variant).

## Trunk control programs

Trunk control programs (TCPs) perform all the signaling tasks necessary to interface with the telephony protocol used on the line or trunk. TCPs are loaded onto an AG 2000-BRI board at board initialization. After a TCP has been loaded to the AG 2000-BRI board, the application must start up its protocol before it can use the TCP to perform call control on a specific port.

The following table lists the TCPs that are applicable to AG 2000-BRI boards:

File | Description
--- | ---
nocc.tcp | No call control protocol.
isd0.tcp | ISDN protocol.