Crestron simpl plus language ref 사용자 설명서

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Software Crestron 
SIMPL+
®
18 
z SIMPL+
®
Language Reference Guide - DOC. 5797G
Signed vs Unsigned Arithmetic
ANALOG_INPUT, ANALOG_OUTPUTs, and INTEGER in SIMPL+ are 16-bit 
quantities. A 16-bit quantity can range from 0 - 65535 when it is treated without 
having a sign (positive or negative). If a 16-bit number is treated as signed in 
SIMPL+, the range becomes -32768 to 32767. The range from -32768 to -1 maps into 
32768 to 65535. Expressed mathematically, the mapping is 65536 - 
AbsoluteValue(Number). The values are treated differently depending on whether 
signed or unsigned comparisons are used. Another way is as follows. 
Assignments may be directly done with negative constants, for example:
    INTEGER I, J;
    I = -1;
    J = 65535;
Results in I being equivalent to J.
Example:
    IF (65535 S> 0)
        X=0;
    ELSE
        X=1;
Above, the value of X is set to 1 since in signed arithmetic, 65535 is the same as -1, 
which is not greater than 0.
    IF (65535 > 0)
        X=0;
    ELSE
        X=1;
Above, the value of X is set to 0 since in unsigned arithmetic, 65535 is greater than 0.
Signed
0  -  32767
32768  -
65535
Unsigned
0  -  32767
-32768  -
-1