nRF9160 dk + serial lte modem + gps

RE: nRF9160 dk + serial lte modem + gps

Håkon Alseth — Wed, 30 Sep 2020 06:34:40 GMT

Hi fe-hadella,

I'm glad to hear that the issue was resolved!

Kind regards,

Håkon

RE: nRF9160 dk + serial lte modem + gps

fe-hadella — Tue, 29 Sep 2020 23:00:45 GMT

Akash helped me with the ping issue. My program was not pinging correctly due to non-escaped quotes. So, now our board and the DK are working the same.

RE: nRF9160 dk + serial lte modem + gps

fe-hadella — Tue, 29 Sep 2020 20:54:51 GMT

The only other thing I can think of is the DK's SIM was used with the asset tracker fw when I first used the unit. I had to load some credentials json file onto it to get it to work. Is this needed for use with the serial lte modem?

RE: nRF9160 dk + serial lte modem + gps

fe-hadella — Tue, 29 Sep 2020 20:31:31 GMT

Hello again. Yesterday, I was able to get GPS working on the nRF9160DK and our board. I am experiencing weird issue with the nRF9160DK compared to our custom board. They are both using the 1.2.1 modem fw, and are loaded with the 1.3.1 version of serial lte modem targeted to the dk board. Our board only has the UART interface and a gpio to toggle power to the nRF9160. The nReset pin is floating normally -- we have this pin routed to a jtag style connector.

I captured two logs today comparing the DK board to our board. I've noticed some commands in the LTE monitor seem to spam other commands as side-effects, so I have repeated those commands using our board too. It seems like the LTE monitor is not operating our custom board via the debug out, so I made the log manually using terminal.

devzone.nordicsemi.com/.../2020_2D00_09_2D00_29T19_5F00_08_5F00_05.836Z_2D00_log.txt

Here is a log on our board via terminal output. My lte2 program just sends the AT commands then polls the uart for the responses.

devzone.nordicsemi.com/.../sirius_5F00_lte_5F00_log.txt

Both SIM cards are Hologram units. The difference between the output is that the DK version is able to perform the XPING command successfully, while our custom board is not. The output otherwise appears the same. Am I missing something in terms of the commands, or is there a possible issue with the SIM card?

Regards,

fe-hadella

RE: nRF9160 dk + serial lte modem + gps

fe-hadella — Mon, 28 Sep 2020 23:31:18 GMT

I was also actually able to enable LTE and have GPS working our board using the PSM command. Below is the output of the `AT+CGDCONT?` command. I can see from the Hologram website that the device is connecting to the network. However, I am not able to ping anything. It seems like the device is connecting to the tower and the network, but not the Internet.

[root@beaglebone:~/swedar_sirius_linux/build# ./test/lte2 AT+CGDCONT?
+CGDCONT: 0,"IP","hologram","10.95.222.57",0,0
OK

On our device, so far, I am just sending the "AT+CFUN=1" once I power the unit. After a few seconds, I can see the +CGDCONT? returns what looks like an IP.

In the LTE viewer, when I type "AT+CFUN?" as a side-effect, there are a number of commands which seem to be executed by the program. On the dk, I have been able to both connect to the network and ping things on the Internet. Is there some command necessary to connect to the Internet?

Regards,

fe-hadella

RE: nRF9160 dk + serial lte modem + gps

fe-hadella — Mon, 28 Sep 2020 23:25:11 GMT

That worked on the dk and our board! Thanks.

RE: nRF9160 dk + serial lte modem + gps

Akash Patel — Mon, 28 Sep 2020 22:12:55 GMT

Hi fe-hadella

The command name was changed in NCS v1.3.x. It is now called AT#XGPS=<op>[,<mask>] which you can see here. There have been a number of changes to the command names for the other commands as well in NCS v1.3.x.

Here is an example sequence of commands from the boot up of the example:

AT%XSYSTEMMODE=0,0,1,0
AT%XMAGPIO=1,0,0,1,1,1574,1577 <-- This command is for DK v0.9.0
AT+CFUN=1
AT#XGPS=1,3 <-- 3 as the mask shows the satellites in view

If you have not enabled LTE on the board, then you do not need to go into PSM or eDRX to use GPS.

Here is an example of the commands running on my board and obtaining a fix:

I was using DK v0.9.0 with modem firmware v1.2.1 and NCS v1.3.1

Regards,

Akash

RE: nRF9160 dk + serial lte modem + gps

fe-hadella — Mon, 28 Sep 2020 20:06:34 GMT

I loaded the serial lte modem software onto the nRF9160 dk and repeated the test, this time attempting to go into the low power mode. This first run used the AT+CPSMS command.

devzone.nordicsemi.com/.../2020_2D00_09_2D00_28T19_5F00_42_5F00_40.169Z_2D00_log.txt

I also tried the AT+CEDRXS command.

devzone.nordicsemi.com/.../2020_2D00_09_2D00_28T19_5F00_52_5F00_50.039Z_2D00_log.txt

I am not sure if there is an order issue or anything. If `AT%XSYSTEMMODE=0,0,1,0` then it would not connect to the lte. When the system mode was "1,0,1,0" then it would connect.

I did load the gps sample onto the dk board, and was able to verify the gps is working with that firmware. Like I mentioned in the previous post, the gps commands seem to lock up the dk board up.

Regards,

fe-hadella

RE: nRF9160 dk + serial lte modem + gps

Håkon Alseth — Mon, 28 Sep 2020 12:10:34 GMT

Hi,

I see that you're using a hologram roaming SIM.

Entering one of the lower power modes, PSM or eDRX successfully, is required for the GPS to be able to run successfully while you have a LTE connection.

Are you able to enter eDRX or PSM with hologram in your area? You can request PSM by using the AT+CPSMS command, and you should be able to get the intervals by issuing "AT+CEREG=5" and when you have attached fully to the network, issue a "AT+CEREG?" to get the connection details.

You should now get two bit patterns back, to reflect if PSM is enabled.

Kind regards,

Håkon