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Unread 05-02-2006, 14:04
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Eldarion Eldarion is offline
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Re: Stupidest Programming Mistakes

One of the things that keeps tripping us up is that the MPLAB compiler does not follow standard C data type promotion rules.

For example, given the statement below, standard C would promote both data types to integer, then multiply. The MPLAB compiler, however, multiplies a and b as unsigned chars and then sticks the result in the integer value, resulting in an overflow where you least expect it!

Code:
unsigned char a = 127:
unsigned char b = 127;
int result;

result = (a * b);
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