Reference Manual

Turbo PMAC/PMAC2 Software Reference
Turbo PMAC Mathematical Features 487
If the divisor is equal to 0, the result will saturate at +/-2
47
(+/-2
23
for an integer division in a compiled
PLC). No error will be reported, and the program will not stop. It is the programmer’s responsibility to
check for possible division-by-zero errors.
Execution time, 80 MHz CPU: 3.6 µsec interpreted, 1.6 µsec compiled floating-point, 0.73 µsec compiled
fixed-point
Examples:
(L1 and M1 are integer variables; P1 is a floating-point variable)
Command
Result
P1=10*2/3
6.666666667
P1=10*(2/3)
6.666666667
M1=10*2/3
7
M1=10*(2/3)
7
L1=10*2/3
7
L1=10*(2/3)
10
%
Function: Modulo (remainder)
The % sign causes the calculation of the remainder due to the division of the numerical value preceding it
by the numerical value following it. Unless the division is executed in a compiled PLC on a line with
only L-variables and integers, the division operation is always a floating-point calculation (even if integer
values are used). The quotient is computed as a floating-point value, then truncated to the next lowest
(i.e. toward -∞) integer so the remainder can be computed.
If the divisor “n” is a positive value, the modulo result is in the range 0 ≤ Result < n. If the divisor “n” is
a negative value, the modulo result is in the range –n ≤ Result < n.
Multiplication, division, modulo (remainder), and bit-by-bit and operations have higher priority than
addition, subtraction, bit-by-bit or, and bit-by-bit exclusive-or operations. Operations of the same priority
are implemented from left to right.
If the divisor is equal to 0, the division will saturate and the modulo result will be 0. No error will be
reported, and the program will not stop. It is the programmer’s responsibility to check for possible
division-by-zero errors.
Execution time, 80 MHz CPU: 3.3 µsec interpreted, 1.4 µsec compiled floating-point, 0.78 µsec compiled
fixed-point
Examples:
Operation
Result
11%4
3
-11%4
1
11%-4
3
-11%-4
-3
3%2.5
0.5
-3%2.5
2
3%-2.5
-2
-3%-2.5
2