Hi - check that the stack isn't overflowing, this would cause all kinds=20
of crazy problems.  How much stack space sscanf() needs could vary=20
widely depending on what you're trying to do.  Some implementations of=20
sscanf() (like the TI code composer studio for ARM Cortex M3) use more=20
than 1K doing not much at all.

How to know if the stack overflows?  Someone else will have to help, I=20
don't know the dsPIC nor the C30 compiler.  There are techniques that=20
fill the stack with a 'sentinel value' (say 0x55) early in main() and=20
then in the main application loop verify that the last available byte in=20
the RAM for the stack is 0x55.  If it isn't, you used up all the stack=20
and very likely have overflowed.

There may be a way to tell the C30 compiler how much stack to reserve.=20
Try making it really big to see if it magically fixes sscanf().

Just my 2c.

J

Bob Blick wrote:
> Welcome to the Piclist.
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> it, it is not automatically added!
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>
> I have taken the liberty of adding the [PIC] tag to your post.
>
> Best regards, Bob
>
> On Fri, Aug 9, 2013, at 06:14 PM, Mascalzone Latino wrote:
>> I'm using a *Microchip C30 compiler* on *dsPIC33F family* and struggling
>> A
>> LOT with *sscanf() function*. Please please please help me because my
>> project is getting stuck for this little detail. I really hope that
>> someone
>> can help me, I haven't found anything on internet and I spent the last 2
>> days on this issue. Thanks a lot in advance*THE TASK*I have to read
>> different types of numbers from a string (unsigned int, float, char and
>> unsigned char).*THE ISSUES*I have problems reading numeric char and
>> unsigned
>> char (i.e. 8 bit numbers, not ASCII characters), but not the other ones.
>> With problem I mean that sscanf() fails (crashes) during its execution
>> without returning any numeric value. In particular the problems come whe=
n
>> I
>> try to read more than one char (or unsigned char) in a row.  As a char
>> conversion specifier I use %hhd, but I tried - at least I think - with
>> all
>> the possible combinations. For unsigned char I used %hhu.In order to
>> understand better please look at this examples with just float and char.
>> Float are read correctly, char just in case A) with one char
>> parameter.*A)
>> JUST ONE CHAR HAS TO BE READ: it works correctly*// 99 init values just
>> for
>> debugging resonschar string[] =3D "test1 12,1.525,2.789";char theChar1 =
=3D
>> 99;float theFloat1;float theFloat2;int retVal =3D 99;retVal =3D
>> sscanf(&string[6],"%f,%f,%hhd",&theFloat1, &theFloat2, &theChar1);*B) TW=
O
>> CHARS HAVE TO BE READ: it doesn't work, sscanf() does not complete its
>> execution and doesn't provide a return value*// 99 init values just for
>> debugging resonschar string[] =3D "test1 12,1.525,2.789";char theChar1 =
=3D
>> 99;
>> char theChar2 =3D 99;float theFloat1;float theFloat2;int retVal =3D 99;r=
etVal
>> =3D
>> sscanf(&string[6],"%f,%f,%hhd,%hhd",&theFloat1, &theFloat2, &theChar1,
>> &theChar2);*C) THREE CHARS HAVE TO BE READ: it doesn't work, sscanf()
>> does
>> not complete its execution and doesn't provide a return value*// 99 init
>> values just for debugging resonschar string[] =3D "test1
>> 12,1.525,2.789";char
>> theChar1 =3D 99; char theChar2 =3D 99;float theFloat1;float theFloat2;in=
t
>> retVal
>> =3D 99;retVal =3D sscanf(&string[6],"%f,%f,%hhd,%hhd,%hhd",&theFloat1,
>> &theFloat2, &theChar1, &theChar2, &theChar3);*THANKS SO MUCH FOR YOUR
>> HELP!!!*
>
--=20
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