Kinetis Design Studio中的主题 Re: PRINTING FLOAT

PRINTING FLOAT

kooroshhajiani — Tue, 15 Mar 2016 18:27:57 GMT

Hi,

My target is TWR-K54F10M and I'm using KSDK1.2 and KSDK1.3 and DSK3.0.

I'm not able to print float values using PRINTF macro(debug_printf).

I have turned on the switch -u _printf_float and it shows up in the linking phase of the build.

However It does not work.

I would appreciate your help.

Regards,

Koorosh Hajiani

Re: PRINTING FLOAT

DavidS — Tue, 15 Mar 2016 18:48:02 GMT

Hi Koorosh,

Please review these posts:

printf() with float values

float printing error in PE

Floating Point on KDS

Regards,

David

Re: PRINTING FLOAT

kooroshhajiani — Tue, 15 Mar 2016 19:06:26 GMT

I found out you need to define a macro in Build setting:

Now however I'm having issues with using sprintf with floats.

Any Ideas,

Regards,

Koorosh Hajiani

Re: PRINTING FLOAT

DavidS — Tue, 15 Mar 2016 19:11:26 GMT

Please also add the "SCANF_FLOAT_ENABLE" as you did with the "PRINTF_FLOAT_ENABLE".

Regards,

David

Re: PRINTING FLOAT

kooroshhajiani — Tue, 15 Mar 2016 19:37:57 GMT

Thanks much. Printf issue is resolved by the solution proposed by Jennie Zhang in the post you provided.

However now I'm having issue with sprintf :

sprintf(out_buff,"%f", flt_val); with the following:

char out_buff[50];

float flt_val;

when I look at out_buff using debugger it is all zeros with flt_val displaying a float as I expect it to.

Can't figure this one out. Is this the GCC arm or KDS.I've used GCC ARM before and never had any issues.

I need to covert a float number to string and I always used sprintf for this purpose successfully until now.

Any ideas?

Thanks,

Koorosh Hajiani

Re: PRINTING FLOAT

kooroshhajiani — Tue, 15 Mar 2016 20:53:32 GMT

Hi David,

Regarding the sprintf not working with float, I noticed that in one of your posts regarding this issue that -u _printf_float switch under the Linker Miscellaneous option , needs to be checked.

When I do this my code hits a trap when it tries to execute sprintf.

So without that option I get all zeros and with those option turned on ,I hit a trap.

Regards,

Koorosh Hajiani

Re: PRINTING FLOAT

DavidS — Wed, 16 Mar 2016 14:47:39 GMT

Hi Koorosh,

You do want the -u _printf_float and -u _scanf_float checked.

Try increasing your task stack size.

If still having issue please post your project.

Regards,

David