Specifications

RELATED PUBLICATIONS
It may be necessary to consult one or more of the
following documents during the installation process. These
manuals will also provide additional guidance if you
encounter technical difficulties during the configuration
process.
LBI-33031 - Rockwell Modem Model R96FT
(19A705178) Maintenance Manual
LBI-38430 - MASTR II, IIe Control Shelf
Maintenance Manual
LBI-38636 - MASTR III Installation Manual
LBI-38662 - IMC Maintenance Manual
LBI-38822 - Turbo Board (GETC 1e) Maintenance
Manual
LBI-38894 - GETC Trunking Card Maintenance
Manual
LBI-38896 - EDACS Site Downlink and CEC/IMC
Uplink Configuration Manual
LBI-38984 - EDACS System Manager User’s Guide
LBI-38988 - EDACS Station GETC Configuration
Manual
LBI-39024 - CEC/IMC Manager (MOM), Version
3.xx Operations Guide.
SRN-1008 - Software Release Notes for GETC CNI
Software
SRN-1010 - Software Release Notes for Turbo
Board Software
SRN-1061 - Software Release Notes for Link GETC
Software
TQ-3353 - MASTR II, IIe, and III PC Programming
Manual
TQ-3357 - GETC Shelf Programming Manual
OPERATION
GENERAL
The CNI GETC performs two basic operations. First, it
converts the Channel Guard tone information in a
conventional transmission to an EDACS compatible Group
Call Assignment message. It then functions as a Downlink
GETC and transfers the EDACS message to the CEC/IMC’s
Uplink GETC.
Second, the CNI GETC functions as a Downlink GETC
when receiving an EDACS message from the CEC/IMC’s
Uplink GETC. For example, the CNI GETC receives an
EDACS message representing a Group Channel Request. It
then converts the EDACS message to a conventional
transmission including the appropriate Channel Guard tone
information using Carrier Activated Squelch (CAS) only.
The CNI GETC performs the conversions between
Channel Guard and EDACS Group ID’s based on
information stored in the CNI GETC’s personality. It is also
possible to convert a single EDACS group to a conventional
transmission without Channel Guard tone.
INTERFACE TO EDACS
The CNI GETC provides the control and conversion
functions necessary to implement EDACS access to the
conventional service area. In addition to performing
conversions between Channel Guard and EDACS formats,
the CNI GETC acts as a message conduit providing a data
communication path between the CNI GETC and the
CEC/IMC. The CNI GETC supports any Channel Guard
Frequency defined in EIA RS-220A between 67.0 Hz and
192.8 Hz (see Specification data for a listing of supported
frequencies).
The CNI GETC decodes Channel Guard information
when receiving a conventional transmission. If the Channel
Guard information matches with the data in the CNI
GETC’s Personality, a Group Call Assignment Message
goes to the CEC/IMC’s Uplink GETC. The CNI GETC
also regenerates the Channel Guard tone information for use
by the CNI GETC’s repeater.
The CNI GETC’s phone modem data is synchronous at
9600 baud using the full duplex operating mode. Data
flows simultaneously in both directions as illustrated in
Figure 2.
This software is subject to change resulting from im-
provements or enhancements. When upgrading the
softwaare, refer to the accompanying software release
notes for software compatibility information.
NOTE
LBI-38986
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