Interconnect Calls, Backup, Status, Overview

OPERATION

LBI-39076B

Backup

The IAM has the capacity to hold 60,000 records in battery backed RAM. Every effort has been made to ensure that this memory won’t be corrupted in normal operation. However, one must not forget about the possibly of component failure in the IAM, or more likely an external influence (such as a lightning strike, technical error, etc.) that could cause the loss of records stored in the IAM. Therefore, you should download the billing data often and backup the data then stored in the office PC to ensure that, if an accident occurs, the loss of data (potential revenue) will be minimized.

As the operation of the IAM is autonomous, the ELI system will continue to process telephone calls, even if the IAM has failed, the IAM memory is full, or the IAM is disconnected from the PCM/Data bus. There is an option in the GTI Configurator that will halt the call processing if there is a bus failure (between units). Because the standard placement of the IAM is at one end of the bus, it is possible that there won’t be any indication to users of the system if the IAM is not able to store Call Detail Records.

However, the IAM has alarm outputs that can be used to notify the user of a memory or bus problem that may result in the loss of billing data (see the subsequent section on alarm outputs). Also, the printer can be used for a hard copy backup of the raw Call Detail Records. The data to the printer can be turned on and off with DIP switch section 5. Up is on and down is off. Do not reset the IAM for this section of the DIP switch.

Status

The status of the IAM can be read by using the GTI Configurator software. The GTI Configurator software will show if an IAM is present, the number of call records presently stored, the amount of memory free and memory used, any alarm conditions, etc. See the GTI Configurator software user’s guide for more information about accessing the IAM for status messages.

Alarms

As described in the installation section, three open drain alarm outputs are provided to alert external equipment in case of problems. Because the IAM does not immediately affect other devices, its operation (or lack of operation) is not immediately obvious, unless someone at the site observes the front panel LEDs, the status of the IAM is read via the GTI Configurator software, or these alarm outputs are monitored.

Alarm 1 - CDR Full or Memory Error - indicates that the CDR buffer is full or a memory error has occurred. In either case, one should access the site (using the GTI Configurator), read the status of the IAM, and download the Call Detail Records (if possible).

Alarm 2 - Bus Failure - is sent if there is a PCM/DATA bus failure and the IAM can’t communicate with the GTI units to receive billing data.

Alarm 3 - Low Battery - is active if the battery backup for RAM is low and should be replaced. (This condition will only be detected during power-up after an extended outage.)

It should be noted that these alarm outputs will go through indeterminate states during IAM power-up or reset. It is recommended that the normally-closed output option be selected (see DIP Switch Settings), so that the presence of individual alarms will indicate the intended alarms, and the presence of all alarms will indicate that the IAM has lost power.

INTERCONNECT CALLS

Overview

The operation of the Enhanced Local Interconnect (ELI) system is controlled by the Site Controller computer. The Site Controller computer makes radio channel and telephone line assignments, based on availability, and the constraints of its active database configuration. For a site that is not connected to a System Manager, the active database configuration is nothing more than what has been programmed into the Site Controller computer's Personality PROMs. For a site that is connected to a System Manager, the active database configuration is the latest site database received from the System Manager.

The Site Controller computer supervises the GTI units by sending and receiving messages over two 19.2 Kbaud serial data links to the Master GTI. (All messages between the Site Controller computer and individual GTI units must first go through the Master GTI.) Message bytes are made up of 8 data bits, 1 stop bit, and no parity bit.

The following terms are used to simplify the descriptions in this section:

∙Telephone-originated call - a call from a telephone, through a telephone line connected to an EDACS repeater site, to one or more radios using that EDACS repeater site.