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13

Have you tried it outdoor? GPS has very low to no reception indoors. Also you have to receive a signal from at least 4 GPS satellites. Smartphones overcome this issue by using the WiFi and cellular strength and a map service where each WiFi network and cell is mapped to GPS coordinates.


7

"Arduino devices" are really just general purpose devices that operate on 5V logic and can be connected to a bus style supported on an Arduino, such as UART, SPI, or I2C, none of which originated with or are unique to it. This means you can use such devices with anything supporting the communication (busing) methodology and a compatible, 5V logic level.1 "...


6

Pipe the output from gpsmon into a file. (if the file exists already and is writable it will be wiped) gpsmon > gpsmon.txt Pipe the output from gpsmon to append to an existing file (provided file permissions allow write access) gpsmon >> gpsmon.txt Use 'tee' command to display on the terminal and pipe to a file at the same time. (same caveats ...


5

my GPS module is based on L80-39 chip, I've installed gpsd and gpsd-clients packages to drive this module, and reboot my Raspberry Pi. you can try those command as following: sudo killall gpsd sudo gpsd /dev/ttyUSB0 -F /var/run/gpsd.socket or Edit /etc/default/gpsd file, input your device name and parameters: sudo systemctl enable gpsd.socket sudo ...


5

Look at adafruit ultimate gps It’s got everything you want and more: -165 dBm sensitivity, 10 Hz updates, 66 channels 5V friendly design and only 20mA current draw Breadboard friendly + two mounting holes RTC battery-compatible Built-in datalogging PPS output on fix >25Km altitude Internal patch antenna + u.FL connector for external active antenna Fix ...


5

You could: utilize a couple of USB to serial adapters like this one. you could use a microcontroller that has multiple serial ports (e.g. arduino mega) to gather the data and transfer it to the Pi, or you could get a serial to I2c or spi adapter that connects to the GPIO pins. More info can be found in this thread.


4

I'm not sure if the script you have found is useful at all: parsing the output of gpspipe with a shell script is anything but fast. You'll most probably get worse clock accuracy using your script than you would by simply synchronizing with pool.ntp.org (unless you don't have network connection at all, or use a modem). Both ntpd and chrony can use GPS time ...


4

The answer is to run a script which reads the GPS, then sets the system time. I found the following code here. Create a bash file with the following: date -s '01/01/2014 00:01' sleep 1 pkill ntpd pkill gpsd gpsd -b -n -D 2 /dev/ttyUSB0 sleep 2 GPSDATE=`gpspipe -w | head -10 | grep TPV | sed -r 's/.*"time":"([^"]*)".*/\1/' | head -1` echo $GPSDATE date -s "$...


4

Your best bet would be using NMEA sentence $GPGGA, that's supported by most GPS receivers out there, format is like this: $GPGGA,hhmmss.ss,llll.ll,a,yyyyy.yy,a,x,xx,x.x,x.x,M,x.x,M,x.x,xxxx*hh 1 = UTC of Position 2 = Latitude 3 = N or S 4 = Longitude 5 = E or W 6 = GPS quality indicator (0=invalid; 1=GPS fix; 2=Diff. GPS fix) 7 = Number ...


4

well it's an old issue, but maybe for others who are searching for a solution, just edit the crontab like follows : @reboot sudo stty -F /dev/ttyAMA0 38400 works also with other commands :)


4

Google Earth is not available for the Linux on ARM. You will need to find an alternative. What about setting up the RPi to generate the KML files then when you need to view the track use your laptop to pull the files and plot them on Google Earth.


4

If you do not want to use USB you can use TTL GPS recievers. Sparkfun does a very fast 50 channel GPS receiver but you can find other ones on eBay or other sites. You can use this by disabling the serial console on the Pi and connect the receiver directly to the UART pins. * Remember to check the voltages of the GPS device you are using


4

this is perfectly normal, especially indoors, where the reception quality is far from ideal. your GPS unit recalculates your position every time, and because of the position error, it thinks you're moving a bit back and forth, hence the non-zero speed readings. to fix this you may get an external antenna or average your coordinates over time to get more ...


4

I believe they are referring to the pin on the hat not the pin on the Pi. If you look at the following picture . You will see pin #4 labeled in the third row of pins across the top. It is a little hard to be sure from the pic but it looks like it is connected to GPIO4.


3

I found a solution from here: https://www.raspberrypi.org/forums/viewtopic.php?f=45&t=53644 The TL;DR is that you run sudo dpkg-reconfigure gpsd and disable USB AutoLoad My steps: sudo dpkg-reconfigure gpsd Start gpsd automatically? Yes Should gpsd handle attached USB GPS receivers automatically? No Device the GPS receiver is attached to: /dev/gps0 (...


3

I faced a similar issue, the way i solved it : 1) check GPS data stream cat /dev/ttyAMA0 => i was able to see the NMEA stream 2) check GPS data with gpsmon gpsmon /dev/ttyAMA0 => it was running well using the stream 3) run dgps in debug mode sudo gpsd /dev/ttyAMA0 -N -D3 -F /var/run/gpsd.sock => it says that it was already running 4) then a ...


3

The baseboard you are referring to doesn't just seem to link the GPIOs, it also seems to have a 3V3 voltage regulator, a independent power supply, and likely a lot of resistors and other components on it as well: Source The board connects to the GPIO P1 header on the P1 (the big one in the corner), which has the following Pins: Source: http://elinux.org/...


3

Yes, This should work with a few caveats (see below). To connect the USB to TTL you would connect a USB cable to the board and then the pins would connect to your GPS module. This will not provide access to the PPS signal from the GPS module (this may not be an issue depending on your project and its requirements. You can work around this by connecting a ...


3

The circuit quite clearly shows that it runs off 5V. It also appears to have provision for external power. The link is quite old (it was obviously designed for a Model B) and the Pi has changed since. The 26 pin header should fit over the 1st 26 pins of the Pi2, although the later Pi changed the physical position of the pins (by a small amount) so it won't ...


3

My chrony.conf now looks like this, and chrony does synchronize with GPS: driftfile /var/lib/chrony/drift makestep 1 10 keyfile /etc/chrony/chrony.keys commandkey 1 allow # set larger delay to allow the NMEA source to overlap with # the other sources and avoid the falseticker status refclock SHM 0 refid GPS precision 1e-1 offset 0.9999 delay 0.2 I haven'...


3

The short answer is no, a magnet will not interfere with your GPS module. The reason is that the electric field strength of the GPS signal will not be altered in any significant way by the relatively modest magnetic field of your magnet. Also, if the intent of the magnet is to temporarily affix the module the metal of your vehicle, most of the magnetic ...


3

Modify /home/pi/serial_nmealog.py so that it logs to syslog. You can configure syslog so that serial_nmealog has its own log file, if you want. Then you can connect with ssh and tail that logfile. There is no way to "interact" with serial_nmealog.py unless it has itself made provisions for that. BTW, I think you can safely drop the sudo from /home/pi/...


3

You have indeed hit on a variable worth controlling! The method that Gary Miller of the NTPsec project settled on was to deliberately add CPU load, automatically adjusted to the thermal readings, to keep the temperature at a higher (but more consistent) level, using his contributed tool ntpheatusb or similar. https://blog.ntpsec.org/2017/03/18/...


3

Those UART GPS modules often have quite poor reception, so you will only get a fix with a clear sky view. Not inside your house, not just out of the window, not on a lawn right next to your house, not under the trees. Additionally, such modules rely on the GPS signal to get the GPS constellation data, which is very slow and can take several minutes. The ...


3

There is a tool called ttybus created exactly for this purpose. Here's an example from their readme page: step 1: create a new tty bus called /tmp/ttyS0mux: tty_bus -s /tmp/ttyS0mux step 2: connect the real device to the bus using tty_attach: tty_attach -s /tmp/ttyS0mux /dev/ttyS0 step 3: create 2 fake ttyS0 devices, attached to the bus: tty_fake -s /...


3

So...a couple of things. Firstly, "why" you need the PPS... Let's back up a bit. In the ancient world of the 1970s and 1980s, when one spoke of "the system clock" or of a system's "clock", one did not mean the Time-of-Day Clock---what is nowadays called a Real Time Clock. The system clock was derived from a crystal oscillator ...


2

GPS has what is known as DOP or Dilution Of Precision. It means things aren't as accurate as you might want. There are 4 such values: TDOP, two HDOP values that are often merged, and VDOP. (Those are Time/Temporal, Horizontal, and Vertical. TDOP should be best, VDOP worst.) All DOPs are measured in meters, and ideally should be under 5. If you get both ...


2

regarding the GPS module, please, see my comment above. BU-353 is cheap, reliable and proven to work. interfacing something else with TTL level shifters from 5V to 3V3 and back is troublesome and eventually will lead to pain and frustration, possibly including burnt unit and/or RasPi. Raspberry Pi has no output power limitations. There's a polyfuse, that ...


2

BU-353 is a bit dated, you should definitely choose BU-353-S4 (SiRF4 instead of SiRF3), otherwise, the choice is between a breakout board, that require soldering, cables and enclosure from one side and complete plug-and-play solution from another side. If you need a GPS to use, drop on your car roof and forget -- you should choose BU-353-S4, but if you ...


2

I found solution (not clean but it works). I added battery to gps, so date and time is saved. In gps chip specification page 22 $GPRMC contains time and date $GPRMC,191822.247,A,2907.1856,N,19016.4938,E,0.03,165.48,031214,3.05,W,A*2C And here is /etc/rc.local #start GPSd gpsd /dev/ttyAMA0 -F /var/run/gpsd.sock # read date & time from GPS /bin/bash /...


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