User's Manual

DRAFT TrimTrac 1.5 Technical Manual v0.3ab 28
position fix even though
there may be actual motion.
fixes, the time to compute a
new fix upon receipt of a
QTKD message will be
marginally longer. No
positions will be logged
between QTKD messages.
Anytime Polling set
“2=Cycled”
Polling Duty-Cycle
Frequency, T19, based on
the desired maximum
response time to a query.
For instance, if a one-hour
response time to a position
query is acceptable, then set
T19 to 3600 seconds;
Polling Duty-Cycle On-
Time, T20, set to 60
seconds.
With these settings, the
device will turn on the
GSM modem once every
hour for 60 seconds.
During the 60 seconds, the
device is able to receive
messages. If T19 is
increased substantially, it
may be beneficial to
increase T20 to 120 or 180
seconds to allow the SMSC
more time to send queued
messages.
When the device is to be
queried for its current
position, send it a
GET_POSITION message
with Position Query Mode
set “P=Compute New
Position”
Upon receipt of the
GET_POSITION message,
the device will compute a
new position fix regardless
of how the Position Age
flag is set.
The device may not receive
the GET_POSITION
message until the next time
Polling Duty-Cycle
Frequency, T19, expires (up
to an one-hour in this
example) or at the next
Scheduled Report time,
whichever is earliest.
Table 7, Minimize Communication Costs and Query-to-Fix
Query-to-Fix Configuration with Weekly status
messages at Sunday 12:00AM UTC and hourly
polling.
See
Page
AT+CTKC= 92
AT+CTKX= 93
Table 8, Sample Non-default Commands for Query-to-Fix Configuration