nRF9160DK UART setup

[Vincent44]

Hello,

I am starting working on a nRF9160DK board, but I am new to this and I am a bit lost.

Using the Dev Academy course and example, I was able to make a small project that sends data to a CoAP server on the push of a button.
I now need to setup a UART connection, in order to chat with an external sensor. Looking at documentation, the high level part seem pretty simple (configuration, callback, etc). However, I am stuck configuring the low level !

I want to keep uart0 for LOG/printk() and setup another UART (Rx and Tx only) to communicate with my external sensor, via the pin header.

I tried many things, but I am still unable to get my project to compile ...

Here is where I am at :

I've created an overlay file and added some code found in this forum.

&uart2{
	status = "okay";
	current-speed = <115200>;
	tx-pin = <16>;
	rx-pin = <17>;
	rts-pin = <0xFFFFFFFF>;
	cts-pin = <0xFFFFFFFF>;
};

In the main, I added:

const struct device *uart= DEVICE_DT_GET(DT_NODELABEL(uart2));

In prj.conf, I added:

CONFIG_SERIAL=y
CONFIG_UART_ASYNC_API=y

Here is what I get when building

First, I get this warning. Compilation keeps going, but it seems that the examples I found are a bit old now...

-- Found devicetree overlay: c:/Users/axelc/Desktop/nRF9160/Mes_Applications/myApp/nrf9160dk_nrf9160_ns.overlay
'tx-pin' is marked as deprecated in 'properties:' in C:/ncs/v2.2.0/zephyr/dts/bindings\serial\nordic,nrf-uarte.yaml for node /soc/peripheral@40000000/uart@a000.
'rx-pin' is marked as deprecated in 'properties:' in C:/ncs/v2.2.0/zephyr/dts/bindings\serial\nordic,nrf-uarte.yaml for node /soc/peripheral@40000000/uart@a000.
'rts-pin' is marked as deprecated in 'properties:' in C:/ncs/v2.2.0/zephyr/dts/bindings\serial\nordic,nrf-uarte.yaml for node /soc/peripheral@40000000/uart@a000.
'cts-pin' is marked as deprecated in 'properties:' in C:/ncs/v2.2.0/zephyr/dts/bindings\serial\nordic,nrf-uarte.yaml for node /soc/peripheral@40000000/uart@a000.

Then, I get the following error

[59/143] Building C object zephyr/drivers/serial/CMakeFiles/drivers__serial.dir/uart_nrfx_uarte.c.obj
FAILED: zephyr/drivers/serial/CMakeFiles/drivers__serial.dir/uart_nrfx_uarte.c.obj 
C:\ncs\toolchains\v2.2.0\opt\zephyr-sdk\arm-zephyr-eabi\bin\arm-zephyr-eabi-gcc.exe -DKERNEL -DMBEDTLS_CONFIG_FILE=\"nrf-config.h\" -DMBEDTLS_USER_CONFIG_FILE=\"nrf-config-user.h\" -DNRF9160_XXAA -DNRF_SKIP_FICR_NS_COPY_TO_RAM -DNRF_TRUSTZONE_NONSECURE -DUSE_PARTITION_MANAGER=1 -D_ANSI_SOURCE -D_FORTIFY_SOURCE=1 -D__LINUX_ERRNO_EXTENSIONS__ -D__PROGRAM_START -D__ZEPHYR_SUPERVISOR__ -D__ZEPHYR__=1 -IC:/ncs/v2.2.0/zephyr/include -Izephyr/include/generated -IC:/ncs/v2.2.0/zephyr/soc/arm/nordic_nrf/nrf91 -IC:/ncs/v2.2.0/zephyr/lib/libc/newlib/include -IC:/ncs/v2.2.0/zephyr/soc/arm/nordic_nrf/common/. -IC:/ncs/v2.2.0/zephyr/subsys/net/lib/coap/. -IC:/ncs/v2.2.0/zephyr/subsys/net/lib/sockets/. -IC:/ncs/v2.2.0/nrf/include -IC:/ncs/v2.2.0/nrf/lib/at_cmd_parser/include -IC:/ncs/v2.2.0/nrf/include/tfm -IC:/ncs/v2.2.0/nrf/tests/include -Itfm/generated/interface/include -IC:/ncs/v2.2.0/modules/hal/cmsis/CMSIS/Core/Include -IC:/ncs/v2.2.0/modules/hal/nordic/nrfx -IC:/ncs/v2.2.0/modules/hal/nordic/nrfx/drivers/include -IC:/ncs/v2.2.0/modules/hal/nordic/nrfx/mdk -IC:/ncs/v2.2.0/zephyr/modules/hal_nordic/nrfx/. -IC:/ncs/v2.2.0/nrfxlib/nrf_modem/include -Itfm/install/interface/include -Imodules/nrfxlib/nrfxlib/nrf_security/src/include/generated -IC:/ncs/v2.2.0/nrfxlib/nrf_security/include -IC:/ncs/v2.2.0/nrfxlib/nrf_security/include/mbedtls -IC:/ncs/v2.2.0/mbedtls/include -IC:/ncs/v2.2.0/mbedtls/include/mbedtls -IC:/ncs/v2.2.0/mbedtls/include/psa -IC:/ncs/v2.2.0/mbedtls/library -IC:/ncs/v2.2.0/nrfxlib/crypto/nrf_oberon/include/mbedtls -IC:/ncs/v2.2.0/nrfxlib/crypto/nrf_oberon/include -fno-strict-aliasing -Os -imacros C:/Users/axelc/Desktop/nRF9160/Mes_Applications/myApp/build/zephyr/include/generated/autoconf.h -ffreestanding -fno-common -g -gdwarf-4 -fdiagnostics-color=always -mcpu=cortex-m33 -mthumb -mabi=aapcs -mfp16-format=ieee --sysroot=C:/ncs/toolchains/v2.2.0/opt/zephyr-sdk/arm-zephyr-eabi/arm-zephyr-eabi -imacros C:/ncs/v2.2.0/zephyr/include/zephyr/toolchain/zephyr_stdint.h -Wall -Wformat -Wformat-security -Wno-format-zero-length -Wno-main -Wno-pointer-sign -Wpointer-arith -Wexpansion-to-defined -Wno-unused-but-set-variable -Werror=implicit-int -fno-pic -fno-pie -fno-asynchronous-unwind-tables -fno-reorder-functions --param=min-pagesize=0 -fno-defer-pop -fmacro-prefix-map=C:/Users/axelc/Desktop/nRF9160/Mes_Applications/myApp=CMAKE_SOURCE_DIR -fmacro-prefix-map=C:/ncs/v2.2.0/zephyr=ZEPHYR_BASE -fmacro-prefix-map=C:/ncs/v2.2.0=WEST_TOPDIR -ffunction-sections -fdata-sections -specs=nano.specs -std=c99 -MD -MT zephyr/drivers/serial/CMakeFiles/drivers__serial.dir/uart_nrfx_uarte.c.obj -MF zephyr\drivers\serial\CMakeFiles\drivers__serial.dir\uart_nrfx_uarte.c.obj.d -o zephyr/drivers/serial/CMakeFiles/drivers__serial.dir/uart_nrfx_uarte.c.obj -c C:/ncs/v2.2.0/zephyr/drivers/serial/uart_nrfx_uarte.c
In file included from C:\ncs\v2.2.0\zephyr\include\zephyr\toolchain.h:50,
                 from C:\ncs\v2.2.0\zephyr\include\zephyr\devicetree\zephyr.h:15,
                 from C:\ncs\v2.2.0\zephyr\include\zephyr\devicetree.h:3931,
                 from C:\ncs\v2.2.0\zephyr\include\zephyr\device.h:12,
                 from C:\ncs\v2.2.0\zephyr\include\zephyr\drivers\uart.h:26,
                 from C:\ncs\v2.2.0\zephyr\drivers\serial\uart_nrfx_uarte.c:11:
C:\ncs\v2.2.0\zephyr\include\zephyr\toolchain\gcc.h:77:36: error: static assertion failed: "/soc/peripheral@40000000/uart@a000 has legacy *-pin properties defined although PINCTRL is enabled"
   77 | #define BUILD_ASSERT(EXPR, MSG...) _Static_assert(EXPR, "" MSG)
      |                                    ^~~~~~~~~~~~~~
c:\ncs\v2.2.0\zephyr\soc\arm\nordic_nrf\common\soc_nrf_common.h:229:9: note: in expansion of macro 'BUILD_ASSERT'
  229 |         BUILD_ASSERT(!IS_ENABLED(CONFIG_PINCTRL) ||                     \
      |         ^~~~~~~~~~~~
C:\ncs\v2.2.0\zephyr\drivers\serial\uart_nrfx_uarte.c:2080:9: note: in expansion of macro 'NRF_DT_CHECK_PIN_ASSIGNMENTS'
 2080 |         NRF_DT_CHECK_PIN_ASSIGNMENTS(UARTE(idx), 1,                            \
      |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
C:\ncs\v2.2.0\zephyr\drivers\serial\uart_nrfx_uarte.c:2193:1: note: in expansion of macro 'UART_NRF_UARTE_DEVICE'
 2193 | UART_NRF_UARTE_DEVICE(2);
      | ^~~~~~~~~~~~~~~~~~~~~
[60/143] Linking C static library zephyr\soc\arm\common\cortex_m\libsoc__arm__common__cortex_m.a
[61/143] Linking C static library zephyr\boards\boards\arm\nrf9160dk_nrf9160_ns\libboards__arm__nrf9160dk_nrf9160.a
[62/143] Linking C static library zephyr\libzephyr.a
[63/143] Building C object zephyr/drivers/pinctrl/CMakeFiles/drivers__pinctrl.dir/pinctrl_nrf.c.obj
[64/143] Linking C static library zephyr\drivers\timer\libdrivers__timer.a
ninja: build stopped: subcommand failed.
FATAL ERROR: command exited with status 1: 'c:\ncs\toolchains\v2.2.0\opt\bin\cmake.EXE' --build 'c:\Users\axelc\Desktop\nRF9160\Mes_Applications\myApp\build'

Could you please help me on solving this. I have the feeling that I am close to what I need, I just miss a small thing in the configuration.

Thanks.

[Naeem Maroof]

Hi Vincent,

Thank you for contacting DevZone at NordicSemi.

Can you please zip and send your complete project to build and reproduce it. Looks like related to the overylay configuration and pinctrl.

Thanks.

Naeem

[Vincent44]

Hi.

Thank you for the quick response. Find attached my test project.

Thanks.

3122.myApp.zip

[Naeem Maroof]

Hi Vincent,

Thank you for sending your project zip.

After compiling the project, I got the similar error:

"error: static assertion failed: "/soc/peripheral@40000000/uart@a000 has legacy *-pin properties defined although PINCTRL is enabled"

This means that we need to use pin control.

Pin control, also referred to as pinctrl, is a Zephyr RTOS API to standardize how SoC peripheral pins are configured. You can read more about it here: Pinctrl

We need to use pinctrl in overylay. Kindly replace the contents of your overlay with this one:

&uart2 {
	compatible = "nordic,nrf-uarte";
	status = "okay";
	current-speed = <115200>;
	pinctrl-0 = <&uart2_default>;
	pinctrl-1 = <&uart2_sleep>;
	pinctrl-names = "default", "sleep";
};

&pinctrl {
	uart2_default: uart2_default {
		group1 {
			psels = <NRF_PSEL(UART_TX, 0, 16)>,
					<NRF_PSEL(UART_RX, 0, 17)>;
		};
	};
};

And re-buid you project. 

Hope it helps,

Naeem

[Vincent44]

It's working now. Thanks a lot !

[Naeem Maroof]

Pleasure to assist you.

Regards,

Naeem