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How to printf("%02X",CBuf) to FF but not to FFFFFFFF

Posted on 1998-12-13
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Last Modified: 2008-02-26
char CBuf;

CBuf=0xFE;
 printf("%02X",CBuf);

I wish the result is FE, but it is FFFFFFFE.
Who can help me this? thanks!
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Question by:wpy
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by:ozo
ID: 1255115
unsigned char CBuf;
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by:wpy
ID: 1255116
thanks !! it work well!
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RONSLOW earned 10 total points
ID: 1255117
the problem is that the %x format is expecting an int.  You have put in a (signed) character with a negative value so the sign bit gets extended (ie. you end up with a negative int).

Either change CBuf to and unsigned char (as suggested) OR
cast it to unsigned char in the printf
eg.

print ("%02x",unsigned char(CBuf));

The best solution depends on what you subsequently want to do with CBuf.  If you are going to put in into a string, then you probably want to keep it a plain char (not make it unsigned) and just cast when you want to see the HEX value.

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