Remote Address; Battery - Comtech EF Data SDM-650B Installation And Operation Manual

Configuration

3.1.1.3 Remote Address

Each modem must be configured for a distinct address between 1 and 255 to
communicate using the established remote communications protocol.
Addresses are programmed by a switch pack (SP2) on the M&C module.
Addresses are binary coded numbers set at SP2. Switch #1 (SP2-1) is the most significant
bit, and switch #8 (SP2-8) is the least significant bit.

3.1.1.4 Battery

A rechargeable battery on the M&C module allows the modem to retain configuration
information without prime power for up to 30 days. A jumper (JP6) is supplied on the
M&C module to disconnect battery power from the backup RAM. During normal
operation, this jumper should be in the ON position. Should the modem be powered-
down, the following sequence is carried out by the M&C microcontroller:
1. When power is applied to the M&C, the microcontroller checks the battery-
2. If the battery-backed RAM failed the valid data test, the modulator, demodulator,
3. If battery-backed RAM and a module failed the valid data test, a default
To erase the configuration stored in RAM, capacitor C12 must be shorted while JP6 is
OFF.
3–4
backed RAM to see if valid data has been retained. If valid data has been
retained, the modem is reconfigured to the configuration maintained in RAM.
and interface modules would be tested to determine if valid configuration
information was retained by them. If valid configuration information was
retained by a module, that module's configuration will be stored in the
battery-backed RAM and maintained.
configuration for the module from ROM is stored in battery-backed RAM and
maintained.
SDM-650B Satellite Modem
Rev. 5