topic printf() in qn908xcdk sample in Wireless MCU

printf() in qn908xcdk sample

toru148 — Tue, 22 Oct 2019 20:09:03 GMT

I try to add printf() in qn908xcdk_wireless_examples_bluetooth_otap_client_att_freertos.

I just copy some code from qn908xcdk_rtso_examples_freertos_hello.

But I always get compile error "undefined reference to `_printf'"

Do you know how to add printf() in qn908xcdk_wireless_examples_bluetooth_otap_client_att_freertos ?

I use MCUXpresso IDE v11.0.1, QN9080SIP development kit.

Re: printf() in qn908xcdk sample

Xiang_Li — Wed, 23 Oct 2019 05:28:59 GMT

How about debug console? See file fsl_debug_console.h/.c

Search function DbgConsole_Init() globally in SDK to see examples of how to use it. For example, check demo_apps\hello_world project, which does only a serial in/out.

Alternatively, you can check the project private_profile_client. And the usage of Serial_Print().

But in this case we need to define a print_buffer[], and use sprintf() if we want to print parameters via Serial_Print().

Re: printf() in qn908xcdk sample

ovidiu_usturoi — Thu, 24 Oct 2019 12:40:31 GMT

Hi toru148@gmail.com‌,

For this linker issue are two options:

1. using SDK_DEBUGCONSOLE. For this we will have to enable this define from project options, like below:

2. using _printf based on the Redlib implementation:

For this let the SDK_DEBUGCONSOLE set to 0 and remove CR_INTEGER_PRINTF

Please also take a look at the SDK_DEBUGCONSOLE_UART define.

(here are also some details for a similar topic: https://community.nxp.com/thread/389140 )

Regards,

Ovidiu

Re: printf() in qn908xcdk sample

toru148 — Thu, 24 Oct 2019 23:03:30 GMT

2nd option worked for me. I got printf() message on Serial port monitor.

Thanks

Re: printf() in qn908xcdk sample

ovidiu_usturoi — Sun, 27 Oct 2019 15:09:19 GMT

Hi toru148@gmail.com‌,

If the issue is fixed, can you please close the ticket by using:

- mark an answer as correct:

Mark Correct

- Mark as assumed answered button.

Regards,

Ovidiu