topic RT1170-EVK how enable PRINTF float ? Removing CR_INTEGER_PRINTF did not help? in i.MX RT Crossover MCUs

RT1170-EVK how enable PRINTF float ? Removing CR_INTEGER_PRINTF did not help?

EdOfTheMountain — Mon, 21 Mar 2022 17:46:59 GMT

PRINTF does not print float numbers when %f is used?

I am using PRTINT on RTK1170-EVK M4 core.

Removing CR_INTEGER_PRINTF did not help?

evkmimxrt1170_hello_world_cm4

(void)PRINTF("\r\n[m4]Print float=%f prints nothing?\r\n\n", 3.14);

Example Output:

[m4]Print float=

Re: RT1170-EVK how enable PRINTF float ? Removing CR_INTEGER_PRINTF did not help?

EdOfTheMountain — Mon, 21 Mar 2022 18:26:25 GMT

This solution works. Removing CR_INTEGER_PRINTF by itself did NOT help.

In MCUXpresso, right-mouse click project, select Properties, C/C++ Build > Settings, then MCU C Compiler > Preprocessor

if SDK_DEBUGCONSOLE = 0 then PRINTF is directed to printf() in the C library. Code size is larger, but printf will work for floats.

Add SDK_DEBUGCONSOLE_UART to redirect printf output to UART.

SDK_DEBUGCONSOLE=0
SDK_DEBUGCONSOLE_UART

MCUXpresso Using of printf

Re: RT1170-EVK how enable PRINTF float ? Removing CR_INTEGER_PRINTF did not help?

Desmond_lim — Wed, 01 Jun 2022 05:26:13 GMT

I have similar problems however, when I followed the instructions that were given above, the PRINTF does not even output anything at all.

There is another preprocessor which is PRINTF_FLOAT_ENABLE=0. I changed that to 1 and keep the original settings.

In summary:

1. SDK_DEBUGCONSOLE=1

2. CR_INTEGER_PRINTF (didnt remove)

3. PRINTF_FLOAT_ENABLE=1 (changed from 0 to 1).

And it prints out the float. Anyway, I still need to confirm if that is correct or not.

However, I have a few questions regarding this.

1. Why didnt the SDK keep the preprocessor as 1 by default?

2. Why is the above proposed solution not working for my case?

3. What are those two preprocessors (CR_INTEGER_PRINTF) and (PRINTF_FLOAT_ENABLE=1) doing to be exact? Why do we need them in the first place?

4. Based on my understanding that SDK_DEBUGCONSOLE=1 means using some SDK debug print and not the C printf(), what are the difference between them? Why when I set it 0 and defined the UART preprocessor, I have nothing at all since it should be the standard C printf()?

4. If I am using KEIL and the toolset could be different, do I still need to define all these preprocessor?

Thanks.

Best regards,

Desmond