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2. Macro strings are stored in the serial eeprom. They are included in the backups.
3. A tone sequence library is stored in program ROM. Pointers to the tone sequence
library for particular telemetry sequences are stored in RAM and serial eeprom.
Initialization
Default configuration parameter values are built into the CPU board program. The first
time that the program is started after it is written to the processor chip ROM, it will load
the default parameters into the serial EEPROM and into RAM. On subsequent resets of
the system, the processor checks for a configuration valid byte in the EEPROM, and if it
is correct, the configuration parameters are loaded from the serial EEPROM. A reset is
caused by power cycling, hitting the reset button on the CPU board, by issuing the C000
command, or by the watchdog timer built into the processor detecting a program
hangup.
A reload of the hard coded defaults can be forced on the next reset by resetting the
EEPROM configuration valid byte. There is a command, C100, to do this.
The default parameter load takes about 12 seconds. A beep-beep confirmation is sent to
port 0 when this is complete. If power is interrupted during the default load, it will start
over again on the next reset. Subsequent resets take less than one second.
Any new program load will overwrite the configuration parameter working copy in
serial EEPROM. If the program revision is a minor one with no changes to the EEPROM
parameter memory layout, then previously configured parameters can be restored by
using the restore command. For more significant program updgrades, this will not
work. Therefore, a site manager should keep a record of changes made to the default
configuration so that they can be quickly restored.