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Yagarto tool chain standard IO issues

Posted by Antonio Defina on May 22, 2013
I all,

My name is Antonio. I have a problem with standard I\O functions, in particular with sscanf function. I use Free RTOS on SAM7X micro controller compiled with yagarto tool chain (version 4.7.2). The problem is that sometimes the sscanf does not provide in output the values. For example:

char message[32];
int returnScanf;
int getValue;


getValue = 5;
returnScanf = sscanf(message,"%d",&getValue);

//returnScanf is equal to 1 (correct), but getValue is equal to 0

It is very strange, because sometimes, if I try to compile again the same source code, it sometimes works properly (without changing any header\compiler option, etc.).

I use this compiler options:

-mthumb-interwork \
-mcpu=arm7tdmi \
-Wall \
-g \
-fomit-frame-pointer \

and linker options:

LINKER_FLAGS=-nostartfiles -Xlinker -o$(PROJECTNAME).$(ARMEXT) -lm -Xlinker -M -Xlinker -Map=$(PROJECTNAME).$(MAPEXT)

Could you please help me to find the possible mistake?

Thanks in advance

RE: Yagarto tool chain standard IO issues

Posted by Richard on May 22, 2013
Is your question FreeRTOS related? Is the behaviour the same when executed from main() before the scheduler has started as from a task after the scheduler has started?


RE: Yagarto tool chain standard IO issues

Posted by Antonio Defina on May 31, 2013

the source code example is inserted inside a FreeRTOS task.

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