Omron CP1E-E@@D@-@ Computer Hardware User Manual


 
2 Instructions
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CP1E CPU Unit Instructions Reference Manual(W483)
(3) Precautions in Handling Special Values
The following precautions apply to handling zero, infinity, and NaN.
The sum of positive zero and negative zero is positive zero.
The difference between zeros of the same sign is positive zero.
If any operand is a NaN, the Error Flag will be turned ON and the tests will not be executed.
Positive zero and negative zero are treated as equivalent in comparisons.
Comparison or equivalency tests on one or more NaN will not be executed and the Error Flag will be
turned ON.
Floating-point Calculation Results
When the absolute value of the result is greater than the maximum value that can be expressed for
floating-point data, the Overflow Flag will turn ON and the result will be output as ±∞. If the result is pos-
itive, it will be output as +; if negative, then –.
The Equals Flag will only turn ON when both the exponent (e) and the mantissa (f) are zero after a cal-
culation. A calculation result will also be output as zero when the absolute value of the result is less
than the minimum value that can be expressed for floating-point data. In that case the Underflow Flag
will turn ON.