Data Sheet

LOCOSYS Technology Inc.
20F.-13, No.79, Sec. 1, Xintai 5th Rd.,
Xizhi District, New Taipei City 221, Taiwan
℡ 886-2-8698-3698
 886-2-8698-3699
www.locosystech.com
Page 10/20
© 2006 LOCOSYS Technology Inc.
and then back to normal operation mode.
Start
GPS module is powered on
Change GPS to periodic mode with
3000ms on and 12000ms standby
if position fix is available, otherwise
(18000, 72000) ms will be applied.
unsigned char PeriodicMode[] =
{"$PMTK225,2,3000,12000,18000,72000*15\x0D\x0A"};
GPS module will return message
"$PMTK001,225,3*35\x0D\x0A"
if command is accepted.
Set GPS to normal
operation mode?
No
Yes
GPS is in
standby now
Yes
Issue any byte to GPS
and wait it awake
No
Issue command of
normal operation mode
unsigned char NormalMode[] =
{"$PMTK225,0*2B\x0D\x0A"};
EndEnd
GPS is in normal modeGPS is in periodic mode
Note: minimum on time is 2000ms.
maximum standby time is 518400000ms (6 days)
GPS module will return message
"$PMTK001,225,3*35\x0D\x0A"
if command is accepted.
5.3.3 AlwaysLocate
TM
mode
AlwaysLocate
TM
is an intelligent controller of periodic mode. Depending on the
environment and motion conditions, GPS module can adaptively adjust working/standby
time to achieve balance of positioning accuracy and power consumption. In this mode, the
host CPU does not need to control GPS module until the host CPU needs the GPS position
data. The following flow chart is an example to make GPS module go into
AlwaysLocate
Tm
mode and then back to normal operation mode.
Note: AlwaysLocate
TM
is a trade mark of MTK.