Cannot print more than two values in a single command line using NRF_LOG_FLOAT_MARKER

[Shri1395]

Hi, 

I have been trying to print out the float values using the NRF_LOG_FLOAT_MARKER, and i am only able to print 2 values in a single NRF_LOG_INFO line. Is there a way to print 3 values in a single line?

Currently this is what i have been using to print 2 values:
NRF_LOG_INFO("Data 1: "NRF_LOG_FLOAT_MARKER" Data 2: "NRF_LOG_FLOAT_MARKER" \r\n", NRF_LOG_FLOAT(Value_1), NRF_LOG_FLOAT(Value_2));
NRF_LOG_FLUSH();

But if i want to print 3 values:

NRF_LOG_INFO("Data 1: "NRF_LOG_FLOAT_MARKER" Data 2: "NRF_LOG_FLOAT_MARKER" Data 3: "NRF_LOG_FLOAT_MARKER"\r\n", NRF_LOG_FLOAT(Value_1), NRF_LOG_FLOAT(Value_2), NRF_LOG_FLOAT(Value_3));
NRF_LOG_FLUSH();

I get an error, saying: undefined reference to `LOG_INTERNAL_9'

[masterLee]

Hi, I  checked Jørgen's solution and it works fine Here is an example

          
main(){
    char array[100] = {0};
    ...
    ... // whatever your code is
    ...
    sprintf(array,"%.2f %.2f %.2f %.2f", floatVal_A, floatVal_B, floatVal_C, floatVal_D);
    NRF_LOG_INFO( " Float Values are: %s", array);
}

Regards

[GT]

Thanks for the solution. Unfortunately "%f" does not work. Nothing gets updated on the array pointer. Do you know what needs to be done to enable %f output? Though NRF_LOG_FLOAT_MARKER works but that doesn't use %f.

[masterLee]

This sounds to me like you have not enabled the float option in the project printf/scanf options.

[awneil]

masterLee said:

I  checked Jørgen's solution and it works fine Here is an example

Actually, that is not an example of what Jørgen Holmefjord said at all!

The whole point of the NRF_LOG_FLOAT_MARKER is that it lets you print floats without using %f - and the extra library code which that requires.

GT said:

Thanks for the solution

Unfortunately, it was wrong!

GT said:

"%f" does not work

Indeed - as masterLee says, you need additional library support to use %f.

See also:

https://devzone.nordicsemi.com/f/nordic-q-a/50243/pca10056-and-float

[masterLee]

I would suggest  to take a fresh example from the SDK. You may have changed something in your code and you can to remember it. Next do the following

1) Modify the printf/scanf options as mentioned before

2) Create a character array (i.e. char my_array[50] = {'\0'} ) and a float variable(i.e. x=3.14).

2) use sprintf since it is the most straight forward choice (in my opinion)

  sprintf(str, "Value of Pi = %f", x);

3)Open the CMSIS Configuration wizard. Under nrf_log enable NRF_LOG_ENABLED and BACKEND_RTT

4) Write something on the segger serial port. Also enable RTT J-link view