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- - minigpsd - 0.30-pre1 beta (https://talk.maemo.org/showthread.php?t=24205)

Re: minigpsd - 0.30-pre1 beta

rc5 is out now. Updates will NOT kill the hildon desktop to update the icons (I don't know how else to do this) automatically. Shutting off and restarting, or using an xterm to "killall hildon-desktop" will work.

I wanted to wait to have a python-efficient interface, but I managed to do it early. The icon is updated in the python app/applet now. And adding very fast updates to other applications will be very easy.

(Note I put logging first, so if kml is enabled, that will be saved first and most accurately, but the UI will also update rapidly, just not at the highest priority)

I am writing out a structure to /tmp/mgpstate upon change and idle, but generally it will reflect any changes. There is a header file which defines the structure and contains all the position and fix information.

For general use, all you need to do is open the file and mmap it to a structure pointer, then just use the data. Python can use struct to access it. To update the data in an application, all that is needed is a copy and convert.

Here is the structure:

Code:

struct satinfo {

  // satellite number, elevation, azmuith, and signal

  // satellite number is NEGATIVE if used

    short num, el, az, sn;

};



struct gpsstate {

  // latitude, longitude in micro-degrees.  Altitude in feet * 1000

    int llat, llon, alt;

  // dilution of precision * 1000

    int pdop, hdop, vdop;

  // speed, mph * 1000, track, degrees * 1000

    int gspd, gtrk;

  // year (in century, 08 not 2008), month, day, hour, minute, second, thousanths

    int yr, mo, dy, hr, mn, sc, scth;

  // lock, 0-1.  fix from GPGSA

    int lock, fix;

  // -1 if device not connected

    int gpsfd, obdfd;

  // number of sats visible, number being used in fix

    int nsats, nused;

  // satellite table

    struct satinfo sats[20];

};

And a sample in Python:

Code:

#!/usr/bin/env python



import struct

import mmap

import time



file = open("/tmp/mgpstate", "r+")



data = mmap.mmap(file.fileno(), 244)



print "lat,lon"

while True:

    gpstate = struct.unpack("21i80h",data)



    print "lat=",float(gpstate[0])/1000000

    print "lon=",float(gpstate[1])/1000000

    print "alt=",float(gpstate[2])/1000



    print "pdop=",float(gpstate[3])/1000

    print "hdop=",float(gpstate[4])/1000

    print "vdop=",float(gpstate[5])/1000



    print "spd=",float(gpstate[6])/1000

    print "trk=",float(gpstate[7])/1000



    print gpstate[10],"/", gpstate[9], "/",gpstate[8]

    print gpstate[11],":", gpstate[12], ":",gpstate[13], ".", str(gpstate[14]).zfill(3)



    print "lock=",gpstate[15]

    print "fix=", gpstate[16]



# BT gps, obd status    print gpstate[17], gpstate[18]



    sats = gpstate[19]

    print "sats=", sats," used=", gpstate[20]



    for i in range(sats):

        j=21+i*4

        print gpstate[j],gpstate[j+1],gpstate[j+2],gpstate[j+3]



    time.sleep(1) #use 0.2 for 5hz, etc.

Re: minigpsd - 0.30-pre1 beta

Quote:

Originally Posted by tz1 (Post 242871)

rc5 is out now.

I am writing out a structure to /tmp/mgpstate upon change and idle, but generally it will reflect any changes. There is a header file which defines the structure and contains all the position and fix information.

Out of curiosity: Is this intended for cooperation with carman ?

Regards,
Hakan

Re: minigpsd - 0.30-pre1 beta

Carman was what motivated me since I already did half of the work to get the minimal test working.

I also needed a way to do a python UI that didn't do a lot of complex sending and receiving of data with minigpsd - mainly for a dashboard application similar to carman (how fast does carman update - Mine was doing 16fps but using over 50% cpu using my NMEA style socket interface).

It should also work with MaemoMapper and anything else without all the ugly decode logic duplication (I have to do it once in minigpsd, then everyone else seems to duplicate it if they don't use the gpsd api directly like gpxview).

Redoing the carman glue should be just slightly bigger than the very simple version since I now have to convert my integers to their floats. But if I do a mmap, carman won't have to read the file, just access the information from the structure periodically.

Re: minigpsd - 0.30-pre1 beta

Quote:

Originally Posted by tz1 (Post 242871)

Hey tz1,

If you want to update the hildon icon cache automatically without rebooting add this to your postinst script, or run it manually from xterm, etc.

Code:

gtk-update-icon-cache -f /usr/share/icons/hicolor

jbk

Re: minigpsd - 0.30-pre1 beta

JBK - thanks, but it isn't the icon cache (I draw them in real-time). I need to RELOAD the taskbar and statusbar applets (written in Python) so they will use the new python code. Disabling and re-enabling them in the control panel would work too.

rc6 is coming shortly. The SOURCE archive contains an example program in C that will use the mmap interface to print out GPS data repeatedly. (It also has the python version). Neither of these are built or installed in the armel deb, but for those who want to integrate support into their own programs this is where to start. Also note I don't fully protect things (check if file exists, etc.) in the examples, but do in mgsetuplib.py

The only functional update in rc6 is if you have the logging directory set to a memory card, and the memory card is not inserted, it prints a message that logging is disabled instead of something else (like filling the internal flash). I also cleaned up the icon update handling code a bit.

Re: minigpsd - 0.30-pre1 beta

For the icons: can someone try to see if killall -HUP hildon-desktop works?

OR this solution proposed here http://www.internettablettalk.com/fo...ad.php?t=25141 -- similar problem?

Re: minigpsd - 0.30-pre1 beta

0.30.0 is in process to be moving to Extras. Bluez-utils-test should be moving there around the same time

0.31-pre0c is in Extras-devel. Please use that thread for questions, comments, etc.

http://www.internettablettalk.com/fo...ad.php?t=25142

Re: minigpsd - 0.30-pre1 beta

Does minigpsd use the a-gpsd data?

Re: minigpsd - 0.30-pre1 beta

The AGPS stuff applies (so far) ONLY to the internal n810 GPS chip, and will be used (or not) automatically when that chip is activated. (At least minigpsd is activating the chip using a high enough level command that the gpsdriver program will query agps/supld for satellite info).

minigpsd will use the internal n810 gps if instructed to.

If AGPS is installed and set up properly, the internal n810 gps will use that data.

If the n810 internal GPS is not being used, then the AGPS will not be used.

Re: minigpsd - 0.30-pre1 beta

Quote:

Originally Posted by tz1 (Post 236481)

The OBD adapters I know get 12 volts through the 16 pin J1962 connector since it is supposed to go to the battery. I added a passthrough wire to power the bluetooth adapter (pin 9, 3-12v for aircable and many others). On my harley, it has a 4 pin connector, only 3 used, ground, switched 12v, and j1850. The problem with cars and "forget about it" is that it will still draw power - only a little, but enough you wouldn't want to leave it for a week.

Just for completeness: I bought a ELM327 Bluetooth OBD2 CAN-BUS Interface Scanner elm_327 ( http://cgi.ebay.com/ws/eBayISAPI.dll...m=370109454632 ) . If I remove the ignition key from the car, the OBD2 interface is not visible anymore in the bluetooth scan.

I'll leave the interface plugged into the car for a few days, let's see whether my battery dies :D

Regards,
Hakan