User’s Manual GalileoSky GPS Lite (0192)
GalileoSky Ltd
Page
15
Internal Archive Structure
Data archive is stored on the internal flash memory. The Terminal stores data from all the inputs and
interfaces, even when they have no connected sensors, in the internal flash memory archive. If storing all
the data is unnecessary, the dynamic archive can be used (command FLASHARCHIVE, see Service
commands). In this case only the data selected in configuration of the head and main packets will be saved
(commands HEADPACK and MAINPACK, see Server exchange protocol settings).
Any change of configuration of the head and main packets when the dynamic archive is on can cause flash
memory formatting and data loss.
Use of dynamic archive can increase considerably the maximum number of kept pixels up to 58000.
By using the internal flash memory it is possible to choose the order in which pixels are sent to the server.
By default, data are saved in the depth of the data store, i.e. current data are saved before older
data. Transfer in chronological order can be set by command FLASHARCHIVE. After changing the direction
of memorizing data the flash memory will be formatted and data lost.
Note, that only current data are used for the first packet.
GPRS traffic costs optimization
GPRS-traffic costs decrease at online monitoring may be reached by following these advices:
1. Turn off transmission of unused data, for example temperature, acceleration, analogue and digital inputs
values which have no connected sensors. It can be made in Configurator tab Settings\Protocol or by
commands MainPack and HeadPack (see Server exchange protocol settings).
2. Increase points record period. It can be made in Configurator tab Settings\Track or by command
WrPeriod (see Track parameters settings).
3. Increase turning angle at which the device record point, and distance at exceed of which the point is
recorded. It can be made in Configurator tab Settings\Tracks or by command Turning (see Track parameters
settings).
4. Find out from server software developers time of disconnection due to the terminal activity absence.
This parameter should be taken into account at points record period setting or traffic increases due to costs
of restoring connection with the server. Example: points record period at stop is 1200 seconds (20
minutes), server disconnection due to the terminal inactiveness is 180 seconds (3 minutes). The terminal
determines that vehicle stops and switches on timer for the next point record in 20 minutes, in 3 minutes
the server disconnects as it hasn’t received data from the terminal. The terminal tries to reconnect the
server at once. It happens 6 times and only in 20 minutes the terminal sends the next point. As a result of
which traffic costs considerably exceeds savings from points record interval increase.
5. Set coordination filtering at stop so as the terminal can correctly chose points record period. The
terminal can determine stop according to several elements:
accelerometer data (command AccSens section Track parameters setting);
external supply voltage (command MHours section Track parameters setting);
ignition sensor indications (command Ignition section Track parameters setting).
If continuous online monitoring is not necessary it is possible to set packet data transmission (see Stels
mode and package transmission). In this case the device is periodically communicates, sends data from
blackbox and disconnects from the server. Savings due to decrease of costs for one data packet
transmission as at data sending from archive packet size may be up to 1000 byte, and at online monitoring
usually one point is sent (tenths of bytes). At the same time the terminal operation from the battery
increases as during server disconnection periods the device switches GSM-modules off.
