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‘Min Saved Records’ defines minimum number of coordinates and I/O data that should be
transferred with one connection to server. If FM1120 does not have enough coordinates to send
to server, it will check again after time interval defined in ‘Sending Period’
Send period – GPRS data sending to server period. Module makes attempts to send
collected data to server every defined period. If it does not have enough records (depends on
parameter Min. Saved Records described above), it tries again after defined time interval.
GPRS Week Time tab – most GSM billing systems charge number of bytes (kilobytes)
transmitted per session. During the session, FM1120 makes connection and transmits data to a
server. FM1120 tries to handle the session as much as possible; it never closes session by itself.
Session can last for hours, days, weeks or session can be closed after every connection in certain
GSM networks – this depends on GSM network provider. GPRS Context Week Time defines
session re-establish schedule if session was closed by network. New GPRS context is opened if
time is 10 minutes till time checked in table. Therefore if all boxes are checked, FM1120 is able to
open new connection anytime. At scheduled time match FM1120 checks for GPRS session
activity. If GPRS session is alive, FM1120 sends data to server according to Send period
parameter. If it is not, FM1120 checks if it is able to re-establish the session.
Figure 26 GPRS Week Time configuration
Device checks if the time between last saved record and current time is equal or higher
than Time based acquire interval. If so, FM1120 saves record to memory. If not, FM1120 checks
if the distance from last record to current record is equal or higher than Distance based acquire
interval. If so, saves the record to memory. If not and speed is higher than 10km/h, then FM1120
checks if angle difference between last record and current record is equal or higher than Angle
based acquire value. If so, saves the record to memory. These checks are performed every
second.
