Adafruit_GPS library

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MusicManArt
 
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Adafruit_GPS library

Post by MusicManArt »

I have your Ultimate GPS Breakout and it is working well with the Adafruit_GPS library so far. However, when working with a ublox GPS receiver I was having issues getting TinyGPS to update the Baud Rate and GPS NMEA Update (1HZ, 5Hz, etc...) I decided to try the Adafruit_GPS library which would not set it either. Then I noticed something in Adafruit_GPS.h that really stuck out.

According to my information about MediaTek chipset, PTMK220 is the SET POS FIX, PTMK251 is the SET NMEA BAUD RATE, and PTMK300 is for setting the Hz for navigation, (the GPS NMEA update.)
But your library has PTMK220 as the NMEA update, and PTMK300 as the SET POS FIX as shown below:

#define PMTK_SET_NMEA_UPDATE_100_MILLIHERTZ "$PMTK220,10000*2F" // Once every 10 seconds, 100 millihertz.
#define PMTK_SET_NMEA_UPDATE_1HZ "$PMTK220,1000*1F"
#define PMTK_SET_NMEA_UPDATE_5HZ "$PMTK220,200*2C"
#define PMTK_SET_NMEA_UPDATE_10HZ "$PMTK220,100*2F"
// Position fix update rate commands.
#define PMTK_API_SET_FIX_CTL_100_MILLIHERTZ "$PMTK300,10000,0,0,0,0*2C" // Once every 10 seconds, 100 millihertz.
#define PMTK_API_SET_FIX_CTL_1HZ "$PMTK300,1000,0,0,0,0*1C"
#define PMTK_API_SET_FIX_CTL_5HZ "$PMTK300,200,0,0,0,0*2F"
// Can't fix position faster than 5 times a second!

Any chance this can be researched and fixed if needed?

Thanks,
art

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Franklin97355
 
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Re: Adafruit_GPS library

Post by Franklin97355 »


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MusicManArt
 
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Re: Adafruit_GPS library

Post by MusicManArt »

franklin97355 wrote:Here is the command list http://www.adafruit.com/datasheets/PMTK_A08.pdf
Franklin,
Thanks, I already have that. But that is the only document that I have seen that has those definitions. Seems to be some differences between the various implementations of the MediaTek chipset. Use Notepad++ or some other real text editor (as opposed to Notepad) so you don't corrupt it.

Art
Last edited by MusicManArt on Sat Sep 13, 2014 10:55 am, edited 1 time in total.

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Franklin97355
 
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Re: Adafruit_GPS library

Post by Franklin97355 »

This is what I find in the Adafruit_GPS.h file.

Code: Select all

/ different commands to set the update rate from once a second (1 Hz) to 10 times a second (10Hz)
// Note that these only control the rate at which the position is echoed, to actually speed up the
// position fix you must also send one of the position fix rate commands below too.
#define PMTK_SET_NMEA_UPDATE_100_MILLIHERTZ  "$PMTK220,10000*2F" // Once every 10 seconds, 100 millihertz.
#define PMTK_SET_NMEA_UPDATE_1HZ  "$PMTK220,1000*1F"
#define PMTK_SET_NMEA_UPDATE_5HZ  "$PMTK220,200*2C"
#define PMTK_SET_NMEA_UPDATE_10HZ "$PMTK220,100*2F"
// Position fix update rate commands.
#define PMTK_API_SET_FIX_CTL_100_MILLIHERTZ  "$PMTK300,10000,0,0,0,0*2C" // Once every 10 seconds, 100 millihertz.
#define PMTK_API_SET_FIX_CTL_1HZ  "$PMTK300,1000,0,0,0,0*1C"
#define PMTK_API_SET_FIX_CTL_5HZ  "$PMTK300,200,0,0,0,0*2F"
// Can't fix position faster than 5 times a second!
Make sure you have the latest from Github

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MusicManArt
 
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Re: Adafruit_GPS library

Post by MusicManArt »

Which is the same thing I posted. Strange that the various documents describe those two messages differently.

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Franklin97355
 
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Re: Adafruit_GPS library

Post by Franklin97355 »

Which document do you have where they are reversed? Could you post a link?

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MusicManArt
 
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Re: Adafruit_GPS library

Post by MusicManArt »

franklin97355 wrote:Which document do you have where they are reversed? Could you post a link?
Got the document from ublox but can't seem to find the link, although I do have the document name. Here is one of them with MediaTek chipset: NMEA-CommandManual_(FTX-HW-13002).pdf which you can probably find through Google.

Art

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