Multicell Location / here_integration configuration

[Hidastelija]

Hi,

I have trouble configuring Here service for multicell positioning. I've used the service before, but recently updated to NCS 2.0.0. I don't know what are the configuration flags that would print float numbers to string. Currently the only way I can get a location is to modify the here_integration.c file and ask the location without rsrq information.

The here_integrationc file has this template:

#define HTTP_REQUEST_BODY                       \

    "{"                             \

        "\"lte\":["                     \

            "{"                     \

                "\"mcc\":%d,"               \

                "\"mnc\":%d,"               \

                "\"cid\":%d,"               \

                "\"tac\":%d,"               \

                "\"rsrp\":%d,"              \

                "\"rsrq\":%.1f,"            \

                "\"ta\":%d,"                \

                "\"nmr\":["             \

                    "%s"                \

                "]"                 \

            "}"                     \

        "]"                         \

    "}"

That is later used to format the request json:

    len = snprintk(buf, buf_len, HTTP_REQUEST_BODY,

               cell_data->current_cell.mcc,

               cell_data->current_cell.mnc,

               cell_data->current_cell.id,

               cell_data->current_cell.tac,

               here_adjust_rsrp(cell_data->current_cell.rsrp),

               here_adjust_rsrq(cell_data->current_cell.rsrq),

               here_adjust_ta(cell_data->current_cell.timing_advance),

               neighbors);

This is the log of what is happening:

[00:30:50.569,061] <dbg> location: method_cellular_lte_ind_handler: Cell measurements results received
[00:30:50.572,052] <dbg> multicell_location_here: location_service_get_cell_location_here: Generated request body:
{"lte":[{"mcc":244,"mnc":91,"cid":36945675,"tac":4050,"rsrp":-119,"rsrq":%.1f,"ta":10,"nmr":[{"earfcn":474,"pci":105,"rsrp":-120,"rsrq":%.1f},{"earfcn":6300,"pci":417,"rsrp":-110,"rsrq":%.1f}]}]}
[00:30:50.888,702] <inf> cloud_module: RRC mode: Connected
%CESQ: 24,1,7,1
%CESQ: 24,1,12,1
[00:30:56.234,619] <err> multicell_location_here: HTTP status: 400
[00:30:56.234,710] <dbg> multicell_location_here: location_service_get_cell_location_here: Received response body:
{"title":"Bad Request","status":400,"code":"E606400","action":"Please correct the request and retry","cause":"Request body must be a valid JSON formatted Positioning API request object.","correlationId":"b883f1e5-c9d5-4a25-aa66-140321352089"}
[00:30:56.235,137] <dbg> multicell_location_here: location_service_parse_response: No 'location' object found
[00:30:56.235,229] <err> multicell_location_here: Failed to parse HTTP response
[00:30:56.235,229] <err> location: Failed to acquire location from multicell_location lib, error: -35
[00:30:56.235,260] <err> location: Location acquisition failed and fallbacks are also done
[00:30:56.235,260] <inf> position_module: * location_event_handler *
[00:30:56.235,260] <inf> position_module: Getting location failed

The Here service responds with an error as my request doesn't have numbers in the "rsrq" field. I have copied these settings from modem_shell sample:

CONFIG_CBPRINTF_LIBC_SUBSTS=y

CONFIG_MINIMAL_LIBC=n

CONFIG_NEWLIB_LIBC=y

CONFIG_NEWLIB_LIBC_FLOAT_PRINTF=y

Regards,
Ilkka

[Didrik Rokhaug]

Hi,

Try to add CONFIG_NEWLIB_LIBC_NANO=n to your prj.conf, then rebuild the project.

Best regards,

Didrik

[Hidastelija]

Hi Didrik,

I tried the config CONFIG_NEWLIB_LIBC_NANO=n, but it didn't change how the string was formatted. I did check the .config before and after changing CONFIG_NEWLIB_LIBC_NANO. The option was set before and is not set after I added CONFIG_NEWLIB_LIBC_NANO=n in prj.conf.

#

# C Library

#

CONFIG_REQUIRES_FULL_LIBC=y

CONFIG_SUPPORT_MINIMAL_LIBC=y

CONFIG_NEWLIB_LIBC=y

# CONFIG_EXTERNAL_LIBC is not set

CONFIG_HAS_NEWLIB_LIBC_NANO=y

# CONFIG_NEWLIB_LIBC_NANO is not set

CONFIG_NEWLIB_LIBC_MIN_REQUIRED_HEAP_SIZE=8192

CONFIG_NEWLIB_LIBC_FLOAT_PRINTF=y

# CONFIG_NEWLIB_LIBC_FLOAT_SCANF is not set

# CONFIG_NEWLIB_LIBC_HEAP_LISTENER is not set

CONFIG_STDOUT_CONSOLE=y

# end of C Library

However, I noticed the OS Support Library has a config CONFIG_CBPRINTF_FP_SUPPORT. After I added CONFIG_CBPRINTF_FP_SUPPORT=y in my prj.conf, Here location started working.

Here is what I have in prj.conf:

CONFIG_CBPRINTF_LIBC_SUBSTS=y

CONFIG_CBPRINTF_FP_SUPPORT=y

CONFIG_NEWLIB_LIBC_NANO=n

CONFIG_MINIMAL_LIBC=n

CONFIG_NEWLIB_LIBC=y

CONFIG_NEWLIB_LIBC_FLOAT_PRINTF=y

And this is from the .config after a building with CONFIG_CBPRINTF_FP_SUPPORT=y

#

# OS Support Library

#

# CONFIG_JSON_LIBRARY is not set

# CONFIG_RING_BUFFER is not set

# CONFIG_BASE64 is not set

# CONFIG_PRINTK_SYNC is not set

CONFIG_MPSC_PBUF=y

# CONFIG_SHARED_MULTI_HEAP is not set

# CONFIG_WINSTREAM is not set

# CONFIG_MPSC_CLEAR_ALLOCATED is not set

CONFIG_REBOOT=y

# CONFIG_UTF8 is not set

CONFIG_CBPRINTF_COMPLETE=y

# CONFIG_CBPRINTF_NANO is not set

CONFIG_CBPRINTF_FULL_INTEGRAL=y

# CONFIG_CBPRINTF_REDUCED_INTEGRAL is not set

CONFIG_CBPRINTF_FP_SUPPORT=y

# CONFIG_CBPRINTF_FP_A_SUPPORT is not set

# CONFIG_CBPRINTF_FP_ALWAYS_A is not set

CONFIG_CBPRINTF_N_SPECIFIER=y

CONFIG_CBPRINTF_LIBC_SUBSTS=y

# CONFIG_CBPRINTF_PACKAGE_LONGDOUBLE is not set

# CONFIG_CBPRINTF_STATIC_PACKAGE_CHECK_ALIGNMENT is not set

There are now two options that both define floats for printf.
CONFIG_NEWLIB_LIBC_FLOAT_PRINTF=y  / This is required at least by CJSON_LIB

CONFIG_CBPRINTF_FP_SUPPORT=y / This is needed to get CONFIG_MULTICELL_LOCATION_SERVICE_HERE to work

The build fails, when I set CONFIG_NEWLIB_LIBC_FLOAT_PRINTF=n due to CJSON_LIB dependency. Seems that CONFIG_CBPRINTF_FP_SUPPORT=y increases flash size 1632 bytes.

 At least there is a solution to the original issue. However, the need for several FLOAT_PRINTF related flags feels confusing.