[Mark Williams]

Hi Alex, sorry for the late reply.  how are you going with this?   Do you see the same issues if you run gpsmon only  and not cgps?

Mark --OzzMaker.com --

[Mark Williams]

If you are still having issues, please email sales @ ozzmaker.com

Mark --OzzMaker.com --

[Mark Williams]

we should be able to update the cmux program so that it can workout if the SARA-R5 is in CMUX mode...  ill get back to you on this.

There other issue is strange.  There is a little delay when accessing or leaving the virtual serials, but it should <1 second, this is normal.
What Pi are you using?
Is it overclocked?
Do you have anything else attached or running?

Mark --OzzMaker.com --

[Mark Williams]

Hi Alex

If you dont enable the mux and cold boot the Pi and the SARA-R5, do you get random characters when connecting to Serial0?

In the second scenario, after the reboot... if you get garbage on serial0, can you try and connect the pin highlighted below to ground for 1 second. this will reset the SARA-R5. Then run CMUX again.

Mark --OzzMaker.com --

[Mark Williams]

what version of Python are you using?  you can find this out with python -V

Mark --OzzMaker.com --

[Mark Williams]

no.. go ahead here if you like

Mark --OzzMaker.com --

[Mark Williams]

It is the blue arrow
On the next version, we will place an indicator on the PCB

Mark --OzzMaker.com --

[Mark Williams]

Hi Davide
Its best to us U-center to configure this;

https://ozzmaker.com/using-u-center-to-connect-to-a-raspberry-pi-with-an-attached-berrygps-imu-gsm/

You would also need to disable unneeded GNSS. E.g. just have GPS enabled

 

Mark --OzzMaker.com --

[Mark Williams]

Hi, i am surprised this has taken so long for someone to pick up this mistake.

The image is correct, it is JP12.  Ill get the text updated.. sorry for the inconvenience.

Mark --OzzMaker.com --

[Mark Williams]

Hi

If you want to see NMEA sentences in gpsmon, kill gpsd using sudo killall gpsd Then run gpsmon specifying the serial interface gpsmon /dev/serial0

You should be able to see the HDOP value, this is a good indication of accuracy;
https://ozzmaker.com/gps-position-accuracy-and-how-to-tell-if-you-have-a-good-fix/

For the second GPS, if HDOP is between 0.5-1.2.. seeing other GNSS will not improve the accuracy greatly.
If the HDOP is really high.. then check these two items;
-switch is set to Ext for external antenna. (I assume you already have this set)
-If using external antenna which uses SMA-uFl adapter.. make sure all screws ands nuts, especially on the back of the SMA connector, are tight

 

 

You could also try a more aggressive reset which resets the entire module
echo -e -n "\xb5\x62\x06\x04\x04\x00\xff\xff\x01\x00\x0e\x61" > /dev/serial0

You can also use U-Center to see what exactly is happening.
https://ozzmaker.com/using-u-center-to-connect-to-a-raspberry-pi-with-an-attached-berrygps-imu-gsm/

Mark --OzzMaker.com --

[Mark Williams]

Sorry for the delay.
Do you have any jumper cables? It would be good to do a loopback test on the serial port, connect TX to RX. Open it with minicom, everything you type should be echoed back. Some more info here;

Can you also take a photo of the top half of the BerryGPS-IMU and upload it here. In the past, we have had components been knocked off

Mark --OzzMaker.com --

[Mark Williams]

Can you please show the output of these commands;

<strong>dmesg | grep tty</strong>

<strong>stty -a -F /dev/serial0</strong>

<strong>grep uart /boot/config.txt</strong>
 

Mark --OzzMaker.com --

[Mark Williams]

How do you have the BerryGPS-IMU connected?  is it sitting on top of the Raspberry PI GPIO?

Mark --OzzMaker.com --

[Mark Williams]

Yes, it does.  Maybe the service was offline when you tried?

I just did a test and it worked. see screenshot below.  you also need to enter in a Token  use 6_cr63HodUWcy7bs4tjQ0w

 

Mark --OzzMaker.com --

[Mark Williams]

For <27  that would be for a warm start from previously having a fix... and if no power is lost to the GPS. (this is why there is a superCap included which should last for 1-2 hrs proving battery backup to the GPS.)

It usually takes between 10-30 mins for first time to fix.

We test every unit to see that data is received over serial.  We then test every 10th for GPS, using an external antenna.
Can you share a close up photo of the top half of the board, i want to make sure nothing is missing

 

Mark --OzzMaker.com --

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