GPS Sample code works, but how do you reduce power?

RE: GPS Sample code works, but how do you reduce power?

Martin Lesund — Fri, 30 Aug 2019 12:52:44 GMT

Hi Steven,
The one in master branch is real GPS yes.

The GPS is turned on when the nrf91 goes in PSM mode. The modem firmware does not support all the low power modes for the GPS yet, but there will be some optimizations in the next releases. (near future)

(a stripped-down sample of this can be found here)

RE: GPS Sample code works, but how do you reduce power?

Martin Lesund — Fri, 30 Aug 2019 12:52:41 GMT

Hi Steven,
The one in master branch is real GPS yes.

(a stripped-down sample of this can be found here)

RE: GPS Sample code works, but how do you reduce power?

stevenminnick — Thu, 29 Aug 2019 13:41:07 GMT

Does that add "real" GPS instead of the circle around Nordic's headquarters? What about the low power modes for GPS? I've tested "real" GPS and that works, but I was looking at testing the low power modes.

RE: GPS Sample code works, but how do you reduce power?

Martin Lesund — Thu, 29 Aug 2019 13:37:15 GMT

Hi Steven,

I am sorry for the confusion this older link to the PR may have caused. There was made another PR that added GPS which is now merged with master branch in NCS.

I highly recommend you to update to master branch to test out the real GPS which is added in the asset_tracker sample.

cd ncs/nrf
git checkout master
git pull
west update

cd applications/asset_tracker
west build -b nrf9160_pca10090ns -d build_gps
nrfjprog -e
west flash -d build_gps

Then you can push down the "button_1" for 10 seconds and you will turn on the GPS functionality.

RE: GPS Sample code works, but how do you reduce power?

stevenminnick — Thu, 29 Aug 2019 11:50:09 GMT

Martin, forgive me if I'm missing things, I'm still trying to wrap my head around Git, Github,west and all the branches and versions of all the repos.

Are you showing me "what's default" for the 1.0 tagged release? You are showing me: https://github.com/NordicPlayground/fw-nrfconnect-nrf/blob/v1.0.0/applications/asset_tracker/prj.conf

That works fine. I'm referring to your earlier post where you said:

[quote userid="66115" url="~/f/nordic-q-a/48257/gps-sample-code-works-but-how-do-you-reduce-power/202353"]The new modem firmware supports GPS in PSM mode.
Here is an example code on how you can use it.[/quote]

And that prj.conf file is here (I believe, If I'm using github correctly)

https://github.com/NordicPlayground/fw-nrfconnect-nrf/blob/47ac0f4d375966d8b1c16e30439aef3024a65075/applications/asset_tracker/prj.conf

I'm trying to use the link you posted to try GPS in PSM mode using the example code how to use it and I can't even open the project when I try that code. That prj.conf file has differences. When I try I get those errors and nothing in the output terminal.

RE: GPS Sample code works, but how do you reduce power?

Martin Lesund — Thu, 29 Aug 2019 09:17:35 GMT

Hi Steven,

There is a possibility that you have modified something invalid in the prj.conf file from something else than what's default.

If so please try to change that back.

Then I want you to delete the build folder and then try to open the project again.

If you get a new error, please share what's in the Output terminal:

RE: GPS Sample code works, but how do you reduce power?

stevenminnick — Wed, 28 Aug 2019 18:14:50 GMT

That was the ns version. When I try to select the non ns version I get a different error

CMakeOutput.log

The target system is: Generic - 1.14.99 - arm
The host system is: Windows - 10.0.17134 - AMD64
Compiling the C compiler identification source file "CMakeCCompilerId.c" succeeded.
Compiler: C:/gnuarmemb/bin/arm-none-eabi-gcc.exe 
Build flags: 
Id flags: -c 

The output was:
0


Compilation of the C compiler identification source "CMakeCCompilerId.c" produced "CMakeCCompilerId.o"

The C compiler identification is GNU, found in "C:/git/nRF/ncs/nrf/applications/asset_tracker/build_nrf9160_pca10090ns/CMakeFiles/3.13.2/CompilerIdC/CMakeCCompilerId.o"

Compiling the CXX compiler identification source file "CMakeCXXCompilerId.cpp" succeeded.
Compiler: C:/gnuarmemb/bin/arm-none-eabi-gcc.exe 
Build flags: 
Id flags: -c 

The output was:
0


Compilation of the CXX compiler identification source "CMakeCXXCompilerId.cpp" produced "CMakeCXXCompilerId.o"

The CXX compiler identification is GNU, found in "C:/git/nRF/ncs/nrf/applications/asset_tracker/build_nrf9160_pca10090ns/CMakeFiles/3.13.2/CompilerIdCXX/CMakeCXXCompilerId.o"

Checking whether the ASM compiler is GNU using "--version" matched "(GNU assembler)|(GCC)|(Free Software Foundation)":
arm-none-eabi-gcc.exe (GNU Tools for Arm Embedded Processors 7-2018-q2-update) 7.3.1 20180622 (release) [ARM/embedded-7-branch revision 261907]
Copyright (C) 2017 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

Performing C SOURCE FILE Test toolchain_is_ok succeeded with the following output:
Change Dir: C:/git/nRF/ncs/nrf/applications/asset_tracker/build_nrf9160_pca10090ns/CMakeFiles/CMakeTmp

Run Build Command:"C:/ProgramData/chocolatey/bin/ninja.exe" "cmTC_8d7d6"
[1/2] Building C object CMakeFiles/cmTC_8d7d6.dir/src.c.obj

[2/2] Linking C executable cmTC_8d7d6

c:/gnuarmemb/bin/../lib/gcc/arm-none-eabi/7.3.1/../../../../arm-none-eabi/bin/ld.exe: warning: cannot find entry symbol _start; defaulting to 00008000


Source file was:
int main(void) { return 0; }

CMakeError.log

Compiling the C compiler identification source file "CMakeCCompilerId.c" failed.
Compiler: C:/gnuarmemb/bin/arm-none-eabi-gcc.exe 
Build flags: 
Id flags:  

The output was:
1
c:/gnuarmemb/bin/../lib/gcc/arm-none-eabi/7.3.1/../../../../arm-none-eabi/lib\libc.a(lib_a-exit.o): In function `exit':
exit.c:(.text.exit+0x2c): undefined reference to `_exit'
collect2.exe: error: ld returned 1 exit status


Compiling the CXX compiler identification source file "CMakeCXXCompilerId.cpp" failed.
Compiler: C:/gnuarmemb/bin/arm-none-eabi-gcc.exe 
Build flags: 
Id flags:  

The output was:
1
c:/gnuarmemb/bin/../lib/gcc/arm-none-eabi/7.3.1/../../../../arm-none-eabi/lib\libc.a(lib_a-exit.o): In function `exit':
exit.c:(.text.exit+0x2c): undefined reference to `_exit'
collect2.exe: error: ld returned 1 exit status

RE: GPS Sample code works, but how do you reduce power?

stevenminnick — Wed, 28 Aug 2019 18:06:00 GMT

I'm also now on 4.20a. But the behavior is the same.

RE: GPS Sample code works, but how do you reduce power?

stevenminnick — Wed, 28 Aug 2019 18:05:27 GMT

I had the nrf branch switched over to the main 1.0 one for a while but I switched over to the example referenced above and get this when I tried to open the project.

RE: GPS Sample code works, but how do you reduce power?

Martin Lesund — Thu, 22 Aug 2019 13:10:46 GMT

Hi steven,

Please share screenshots/logs etc. of what is going wrong.

RE: GPS Sample code works, but how do you reduce power?

stevenminnick — Thu, 15 Aug 2019 12:18:59 GMT

I have 4.18, I believe that's the latest.

RE: GPS Sample code works, but how do you reduce power?

Martin Lesund — Thu, 15 Aug 2019 07:56:42 GMT

Please make sure that you have updated correctly following this tutorial.

Then please check the SES download link in the "Getting started Assitant", since it sounds like you have an older version of SES if there are issues opening the project.

RE: GPS Sample code works, but how do you reduce power?

Martin Lesund — Thu, 15 Aug 2019 07:56:42 GMT

Please make sure that you have updated correctly following this tutorial.

Then please check the SES download link in the "Getting started Assitant", since it sounds like you have an older version of SES if there are issues opening the project.

RE: GPS Sample code works, but how do you reduce power?

stevenminnick — Wed, 14 Aug 2019 14:41:16 GMT

Thanks for the link with the example code. I'm still trying to get the IDE to actually open his project without errors. There is a lot of GPS stuff in there, but lack of documentation and failing to open is causing me some issue trying to actually compile and run that code.

RE: GPS Sample code works, but how do you reduce power?

Martin Lesund — Mon, 05 Aug 2019 09:03:34 GMT

Hi Steven,

The new modem firmware supports GPS in PSM mode.
Here is an example code on how you can use it.

From the v1.0.0 release notes:

GPS L1 C/A receiver during LTE PSM mode

- Single shot, fixed interval and continuous tracking modes

RE: GPS Sample code works, but how do you reduce power?

stevenminnick — Fri, 26 Jul 2019 14:18:39 GMT

How about now? 1.0 was released a couple weeks ago. Any chance that was in that release?

RE: GPS Sample code works, but how do you reduce power?

Martin Lesund — Thu, 13 Jun 2019 11:24:01 GMT

Hi Steven,

For the current modem firmware version, the GPS is not "power optimized" and only supports cold start.

However, there will come a more power efficient modem firmware with regards to GPS in the near future.

Please contact your RSM for more details regards to the roadmap, if you do not know who that is please send me a personal message on Devzone and I will help you out.