Location API without Cloud Dependencies (GNSS Only)

RE: Location API without Cloud Dependencies (GNSS Only)

kingston — Fri, 07 Jan 2022 22:31:48 GMT

Charliethanks for this. I was able to verify operation on my end as well. It looks like the key option that I missed in my config was CONFIG_LOCATION_METHOD_CELLULAR=n , I made the mistake of assuming if I didn't call it that the default was n. Also noticed that I needed to leave in at least REST and JWT to satisfy the library.

The rest of my code was the same as yours save for a few small differences from our library versions.

Up and running with a successful test! Thanks so much, I now have a PSM warning but I think that's from the long wait. If I can't run it down I'll start a different ticket. I'll accept this answer and close out.

RE: Location API without Cloud Dependencies (GNSS Only)

Charlie — Fri, 07 Jan 2022 21:41:41 GMT

Hi David,

I modified the original nRF9160: Location sample to make it only request GNSS without A-GPS every 3 minutes. You can compare prj.conf and main.c with original files to find the differences.

devzone.nordicsemi.com/.../ncs180_5F00_nrf9160_5F00_location_5F00_gnss_5F00_without_5F00_agps.zip

Best regards,

Charlie

RE: Location API without Cloud Dependencies (GNSS Only)

kingston — Fri, 07 Jan 2022 15:28:58 GMT

Charlie I just tested a location sample directly from Github, sdk-nrf-main version 1.8.99, the C:\sdk-nrf-main\samples\nrf9160\location sample directory is the one I am using. Within that file the unmodified .prj file contains the contents below. It includes, Cloud, Rest, JWT, and Multicell by default. When I try to set those to "n", I get the error. I'd be glad to attach the zip of the sample project but I couldn't see a way to post it to my response.

#
# Copyright (c) 2021 Nordic Semiconductor ASA
#
# SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
#

# General config
CONFIG_FPU=y
CONFIG_NEWLIB_LIBC=y
CONFIG_NEWLIB_LIBC_FLOAT_PRINTF=y
CONFIG_NRF_MODEM_LIB=y

# Heap and stacks
CONFIG_MAIN_STACK_SIZE=2048
# Extended memory heap size needed for encoding REST messages to JSON
CONFIG_HEAP_MEM_POOL_SIZE=8192
CONFIG_SYSTEM_WORKQUEUE_STACK_SIZE=1536

# Location sample
CONFIG_LOCATION=y
#CONFIG_LOCATION_SAMPLE_GNSS_ANTENNA_EXTERNAL=y

# Logging
CONFIG_LOG=y
CONFIG_LOG_MODE_IMMEDIATE=y

# Network
CONFIG_NETWORKING=y
CONFIG_NET_NATIVE=n
CONFIG_NET_SOCKETS=y
CONFIG_NET_SOCKETS_OFFLOAD=y

# LTE link control
CONFIG_LTE_LINK_CONTROL=y
CONFIG_LTE_NETWORK_MODE_LTE_M_GPS=y
CONFIG_LTE_AUTO_INIT_AND_CONNECT=n
CONFIG_LTE_EDRX_REQ=y
# Request PSM active time of 8 seconds.
CONFIG_LTE_PSM_REQ_RAT="00000100"

# nRF Cloud (for A-GPS and cell location)
CONFIG_NRF_CLOUD_REST=y
CONFIG_NRF_CLOUD_AGPS=y
CONFIG_MODEM_INFO=y # required by CONFIG_NRF_CLOUD_AGPS
CONFIG_MODEM_INFO_ADD_NETWORK=y # required by CONFIG_NRF_CLOUD_AGPS

# Library that maintains the current date time UTC for A-GPS and P-GPS purposes
CONFIG_DATE_TIME=y

# Modem JWT
CONFIG_MODEM_JWT=y

# Multicell location service selection
CONFIG_MULTICELL_LOCATION_SERVICE_NRF_CLOUD=y

RE: Location API without Cloud Dependencies (GNSS Only)

Charlie — Fri, 07 Jan 2022 12:31:05 GMT

Hi David,

Multicell is a Cellular location method option and it should not have effects on AGPS which is a GNSS method option. "[00:00:12.285,034] <err> location: nRF Cloud A-GPS request failed, error: -77" message is from the source code nrf\lib\location\method_gnss.c lines 169-243, which is only used when "CONFIG_NRF_CLOUD_AGPS=y". I suspect the issue is not related to prj options.

We need to find a common ground for our discussion. Could you repeat this issue with the original nRF9160: Location sample? or you can share a minimal sample of your codes that can repeat this issue. I believe it does not need LTE and HTTP connection.

Best regards,

Charlie

RE: Location API without Cloud Dependencies (GNSS Only)

kingston — Thu, 06 Jan 2022 16:09:00 GMT

Thanks Charlie I tried setting CONFIG_NRF_CLOUD_AGPS and REST to n, but it still posts the message. Digging a little deeper it appears that the error is tied to the multicell dependency. When I set CONFIG_MULTICELL_LOCATION_SERVICE_NRF_CLOUD=n i get a build error stating "At least one location service must be enabled" So, it appears that the location lib is requiring multicell, which requires a cloud service...i think. What is the right way to look at the available .prj options for a lib? It's possible I am missing an option to prevent location from including multicell. I hate to waste your time asking questions if I can learn where to look. Thanks!

RE: Location API without Cloud Dependencies (GNSS Only)

Charlie — Thu, 06 Jan 2022 14:28:27 GMT

Hi Devid,

Thanks for your explanation. Do you have set "CONFIG_NRF_CLOUD_AGPS=y" configuration?

I checked that source code it seems the error will happen when you have it set.

Best regards,

Charlie

RE: Location API without Cloud Dependencies (GNSS Only)

kingston — Wed, 05 Jan 2022 16:16:44 GMT

As a follow up, just wanted to note that the device does proceed past the error and continues to get a fix. I was just interested if there is a configuration change I can make to suppress the AGPS request. Looking at the underlying documentation for GNSS API I didn't see an option for disabling AGPS. the developer.nordicsemi.com/.../gnss_interface.html

RE: Location API without Cloud Dependencies (GNSS Only)

kingston — Wed, 05 Jan 2022 15:03:34 GMT

Charlie The Location sample I was referring to is the "location" sample located in nrf\samples\nrf9160\location, it is based on the location library from https://developer.nordicsemi.com/nRF_Connect_SDK/doc/1.8.0/nrf/libraries/modem/location.html#location

Even though I have not configured the use of AGPS, the system appears to still try to use it because I see this error on my serial term with the 9160, "[00:00:12.285,034] <err> location: nRF Cloud A-GPS request failed, error: -77" I have provisioned the device with the credentials for my server, so I'm not surprised that AGPS would fail, but I'm confused why its still trying to use it since I'm never requesting AGPS and only request GNSS only.

I have tested and used the GNSS sample you referred to in the past, that's what I meant when by, "When I test using the GNSS sample I acquire a fix faster than when I use the Location sample with GNSS only". Apologies for the confusion in naming.

RE: Location API without Cloud Dependencies (GNSS Only)

Charlie — Wed, 05 Jan 2022 12:51:19 GMT

Hi David,

I am not sure which "Location example" you used on your application now. The official nRF9160: GNSS sample on NCS1.8.0 uses only GNSS by default, you can test and refer to it for your application.

Best regards,

Charlie