Error: L6218E

[KCY]

I am running into these 3 errors while compiling my program. I tried fixing sdk_config.h.

.\_build\nrf52832_xxaa.axf: Error: L6218E: Undefined symbol app_uart_init (referred from main.o).
.\_build\nrf52832_xxaa.axf: Error: L6218E: Undefined symbol nrfx_twim_enable (referred from main.o).
.\_build\nrf52832_xxaa.axf: Error: L6218E: Undefined symbol nrfx_twim_rx (referred from main.o).

Am I still missing anything else in sdk_config.h to make it work?

[awneil]

Have you added the necessary files to your project?

See: https://devzone.nordicsemi.com/f/nordic-q-a/39503/undefined-reference-on-the-linker-level

[KCY]

Thank you for your response.

I have added app_uart.c in the project, but it seems like "NRF_MODULE_ENABLED" is not enabled. Do you have any idea how to enable this?

For the nrfx_twim_enable problem, I tried solving this by changing the sdk_config, but it didn't work.

Anything else I can try, or am I missing something else? Thank you!

[tesc]

Hi,

Your first screenshot, for some reason, is zoomed out to the point where it is impossible to read the contents, but I suppose that it shows what header files you are including.

Please note that you need to add the c files of the added libraries to the project as well, if you have not done so already.

What are your sdk_config.h settings for the TWI/TWIM peripheral driver legacy layer (TWI_ENABLED, etc.)? See the sdk_config.h of TWI peripheral examples for reference.

Regards,
Terje

[KCY]

Hi Terje,

Sorry for the quality of the uploaded image. Hopefully this one is better. I am trying to show that in my app_uart.c in the project, it seems like "NRF_MODULE_ENABLED" is not enabled and so everything else is grayed out. 

I followed the example given in \examples\ble_peripheral\ble_app_hrs_freertos

The TWI_ENABLED are defined as shown,

#ifndef NRFX_TWI_ENABLED
#define NRFX_TWI_ENABLED 1
#endif
// <q> NRFX_TWI0_ENABLED  - Enable TWI0 instance
 

#ifndef NRFX_TWI0_ENABLED
#define NRFX_TWI0_ENABLED 1
#endif

// <q> NRFX_TWI1_ENABLED  - Enable TWI1 instance
 

#ifndef NRFX_TWI1_ENABLED
#define NRFX_TWI1_ENABLED 0
#endif

And the TWI1_ENABLED are defined as

#ifndef NRFX_TWIM_ENABLED
#define NRFX_TWIM_ENABLED 1
#endif
// <q> NRFX_TWIM0_ENABLED  - Enable TWIM0 instance
 

#ifndef NRFX_TWIM0_ENABLED
#define NRFX_TWIM0_ENABLED 1
#endif

// <q> NRFX_TWIM1_ENABLED  - Enable TWIM1 instance
 

#ifndef NRFX_TWIM1_ENABLED
#define NRFX_TWIM1_ENABLED 0
#endif

Thank you!

[awneil]

So have you added the required .c source files files to your Project?

[tesc]

Hi,

I was not talking about the NRFX_TWI* defines, but the set of legacy layer TWI* defines. Have a look at the sdk_config.h file from a twi example in the SDK (you find them under <sdk folder>/examples/peripheral). There are many defines, such as TWI_ENABLED, TWI0_ENABLED, TWIM_ENABLED, TWIM0_ENABLED, TWIM1_ENABLED, etc. You may need to set both the NRFX_TWI* define and the corresponding TWI* define in sdk_config.h, in order not to get any trouble. If those defines are missing from your sdk_config.h file then you need to copy them (for instance from the sdk_config.h file of one of the twi examples.)

Please also have a look at the comment from awneil regarding .c source files. Are they all added to the project?

Regards,
Terje

[KCY]

I have added these defines but it did not help with the "Undefined symbol nrfx_twim_enable" error.

// <e> TWI_ENABLED - nrf_drv_twi - TWI/TWIM peripheral driver - legacy layer
//==========================================================
#ifndef TWI_ENABLED
#define TWI_ENABLED 1
#endif
// <o> TWI_DEFAULT_CONFIG_FREQUENCY  - Frequency
 
// <26738688=> 100k 
// <67108864=> 250k 
// <104857600=> 400k 

#ifndef TWI_DEFAULT_CONFIG_FREQUENCY
#define TWI_DEFAULT_CONFIG_FREQUENCY 26738688
#endif

// <q> TWI_DEFAULT_CONFIG_CLR_BUS_INIT  - Enables bus clearing procedure during init
 

#ifndef TWI_DEFAULT_CONFIG_CLR_BUS_INIT
#define TWI_DEFAULT_CONFIG_CLR_BUS_INIT 0
#endif

// <q> TWI_DEFAULT_CONFIG_HOLD_BUS_UNINIT  - Enables bus holding after uninit
 

#ifndef TWI_DEFAULT_CONFIG_HOLD_BUS_UNINIT
#define TWI_DEFAULT_CONFIG_HOLD_BUS_UNINIT 0
#endif

// <o> TWI_DEFAULT_CONFIG_IRQ_PRIORITY  - Interrupt priority
 

// <i> Priorities 0,2 (nRF51) and 0,1,4,5 (nRF52) are reserved for SoftDevice
// <0=> 0 (highest) 
// <1=> 1 
// <2=> 2 
// <3=> 3 
// <4=> 4 
// <5=> 5 
// <6=> 6 
// <7=> 7 

#ifndef TWI_DEFAULT_CONFIG_IRQ_PRIORITY
#define TWI_DEFAULT_CONFIG_IRQ_PRIORITY 6
#endif

// <e> TWI0_ENABLED - Enable TWI0 instance
//==========================================================
#ifndef TWI0_ENABLED
#define TWI0_ENABLED 1
#endif
// <q> TWI0_USE_EASY_DMA  - Use EasyDMA (if present)
 

#ifndef TWI0_USE_EASY_DMA
#define TWI0_USE_EASY_DMA 1
#endif

// </e>

// <e> TWI1_ENABLED - Enable TWI1 instance
//==========================================================
#ifndef TWI1_ENABLED
#define TWI1_ENABLED 0
#endif
// <q> TWI1_USE_EASY_DMA  - Use EasyDMA (if present)
 

#ifndef TWI1_USE_EASY_DMA
#define TWI1_USE_EASY_DMA 0
#endif

I have also added the .c files but did not solve the "app_uart_init" error.

Thank you!

[tesc]

Hi,

Sorry for the delay.

In your screenshot I do not see the file nrfx_twim.c in the project. That file is where nrfx_twim_enable is implemented.

What error messages (if any) do you get now? (After adding nrfx_twim.c if missing.)

Regards,
Terje

[KCY]

Thank you very much! The error is now solved! I'm left with the "undefined reference to `app_uart_init'" now.

[awneil]

In your screenshot, the 'code' column next to app_uart.c is empty.

This means there is no code for it - which explains the error.

See: https://devzone.nordicsemi.com/f/nordic-q-a/39798/undefined-reference-to-ble_conn_params_init/154441#154441

[KCY]

Thank you for your advice. I added the app_uart defines and made sure that the 'code' column has something and the error is resolved!