Specifications

Table Of Contents
OPERATIONS
Page 56 MRC-565 Packet Data Radio Operations & Maintenance
5.3.10 Saving and Restoring the Configuration
To aid your understanding how the MRC-565 operational configuration is saved and restored it
is helpful to understand the hardware and design philosophy of the MRC-565.
The MRC-565 is designed to operate unattended in a variety of environments where power may
be applied continuously or intermittently. The goal is for the unit to continue to operate without
loss of messages, data or configuration even if power is randomly turned on and off. Therefore
the software is designed to operate continuously, to save all operational information when power
is off and to resume operation from that point when power is restored.
To support this philosophy, the MRC-565 has three types of memory:
PROGRAM MEMORY (PM)
CONFIGURATION PARAMETER (CPM)
RAM
The PM is non-volatile flash memory that has been programmed with the MRC-565's
operational software (OS). This software contains the initial values of all operational parameters.
The values are referred to as the "factory defaults" because they are programmed into the MRC
MRC-565 operating system software at the factory. The PM can only be modified by replacing
the operating system using the flash download. (Consult XTERMW manual to learn how to
download a new flash into the PM.)
The RAM contains all the dynamic data for the MRC-565. All data logger data, positional data,
and messages entered into the MRC-565 are stored in RAM. Also, all command parameters are
stored in RAM. But RAM is volatile and can only retain information while power is applied.
Turning off or disconnecting power will cause all RAM information to be lost.
During normal operation, the MRC-565 software operates from the data and the parameters that
are stored in RAM. Unfortunately, there are always situations when the RAM data may be lost
or corrupted due to total discharge of the battery, software crash or operator error. Since we do
not want to lose our configuration data during these situations, we have a third type of memory.
The third type of memory, CPM, is also nonvolatile flash memory and retains data even when
power is removed. The MRC-565 retains a copy of all the programmed configuration parameters
in CPM. The MRC MRC-565 will write configuration parameters, which have been entered
from the operator port, into CPM when the SAVE command is entered. Only values that have
changed are written into CPM. Whenever the unit radio ID is changed the MRC MRC-565 will
automatically SAVE the configuration. A validation checksum is used by the MRC-565 to verify
the data in CPM is correct. If the checksum is invalid, the unit will revert to factory defaults.
When the MRC-565 ships from the factory it is programmed with the following default
configuration: the Operator Port (port 0) is set for 9600 baud, 8 data bits, 1 stop bit, no parity,
ASCII protocol and no flow control. This provides a known starting point for communicating to
the unit from a terminal or computer. From this starting point, the user can program the unit ID