Difference between revisions of "GPS"
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== SiRF Star III == | == SiRF Star III == | ||
=== Disable SBAS === | |||
Either use the SiRF Demo program [http://www.sirf.com/SiRFDemo.zip] or these commands to disable WAAS/EGNOS/MTSAT [http://www.gpspassion.com/forumsen/topic.asp?TOPIC_ID=60637]: | |||
$PSRF100,0,<baud rate>,8,1,0 ; Switch to SiRF mode | |||
$PSRF151,00*0E ; WAAS/EGNOS/MTSAT Off | |||
$PSRF151,01*0F ; WAAS/EGNOS/MTSAT On | |||
=== SiRF commands === | === SiRF commands === | ||
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The default update frequency is 1 Hz, or once per second, the MTK chipsets support 5 Hz. | The default update frequency is 1 Hz, or once per second, the MTK chipsets support 5 Hz. | ||
$PMTK300,200,0,0,0,0*2F ; Set 200 millisecond update frequency | |||
$PMTK251,115200*1F ; Baud rate 115200 | |||
$PMTK300,200,0,0,0,0*2F ; ; Again set update frequency | |||
=== Hacks === | === Hacks === | ||
Revision as of 16:51, 30 March 2008
As of today (March 2008) the two best GPS chipsets available are the SiRF Star III and MTK MT3318. They offer fast initial fix and can utilize weak GPS signals by massive parallel correlation computing power [1].
SiRF Star III
Disable SBAS
Either use the SiRF Demo program [2] or these commands to disable WAAS/EGNOS/MTSAT [3]:
$PSRF100,0,<baud rate>,8,1,0 ; Switch to SiRF mode $PSRF151,00*0E ; WAAS/EGNOS/MTSAT Off $PSRF151,01*0F ; WAAS/EGNOS/MTSAT On
SiRF commands
MTK MT3318
Enable 5 Hz
The default update frequency is 1 Hz, or once per second, the MTK chipsets support 5 Hz.
$PMTK300,200,0,0,0,0*2F ; Set 200 millisecond update frequency $PMTK251,115200*1F ; Baud rate 115200 $PMTK300,200,0,0,0,0*2F ; ; Again set update frequency
Hacks
MTK commands
Other chipset brands
- SkyTraq
- Nemerix
- uBlox
- uNav
- Sony
- Fujitsu
