GPS-RECEIVER JP7-T
VERSION 1.02
receiver fails to acquire satellites within a given period of time (approx. 150
sec), the receiver sets itself into the sleep phase. The duration of this sleep
phase is approx. 30 sec. After that, the receiver wakes up, reset itself and
tries to acquire satellites which are in view. This procedure repeats itself
until the initial position computation of GPS receiver is completed.
Hint:
After initial turn on or system reset, the JP7-T will remain in the
full power tracking until a series of Kalman filter navigation
solution is obtained, all ephemeris data is collected and the RTC is
calibrated prior to transitioning to the low power duty cycle mode.
5.3 Push-to-Fix Mode
The Push-to-Fix mode puts the FALCOM JP7-T family into a background
duty cycle which provides a periodic refresh of position, receiver time,
ephemeris data and RTC calibration every 30 minutes. The Push-to-Fix
mode is similar but executive from Trickle Power mode, meaning that only
one mode can be set at a time. In this mode the receiver sets itself into the
sleep phase for 29.5 minutes and a full tracking phase for 30 seconds.
During the tracking phase the JP7-T family acquires satellites, computes
position and updates ephemeris data as well the RTC is being calibrated.
The transition into the Push-to-Fix mode of JP7-T family can be
implemented and configured by using the
Set Operating Mode
command
in SiRFdemo. During the subsequent background cycles or when a user
requests a position update (the RESET_N has to be used) a reset is
generated and a hot start will be typically performed which may take up to a
maximum of 8 seconds. The receiver wakes up, computes its position fix
and goes back to the previous sleep phase again.
5.4 NMEA input message for Trickle Power Mode
The input command message below sets the FALCOM JP7-T family into
the Trickle Power Mode or Push-To-Fix Mode. Details to configure Trickle
Power Mode and Push-To-Fix Modes are described below.
The receiver accepts the input message with following format:
$PSRF107,<
parameter
>, <
parameter
> ,<
parameter
><
* Checksum
><CR> <LF>.
COMAND
SYNTAX
DESCRIPTION
$PSRF107,
ptf
,
dc,
msot
*XX
<CR><LF>
Parameters description:
ptf
// numeric, performs the receiver in one of two pre-defined modes
Possible values:
0: Set the receiver in Trickle Power mode
1: Set the receiver in Push-To-Fix mode
dc
// numeric, Duty Cycle in percent (%)
Possible value:
max 1000: Set the time which will be spent for tracking (
dc% /
10)
msot
// numeric, the on Time in milliseconds
Possible value
200.. 900: Set the time duration of each tracking period
*XX
// C
hecksum has to be calculated in hexadecimal.
This confidential document is the property of FALCOM GmbH and may not be copied or circulated without permission.
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