Yaskawa MP900 Series Ladder Programming Manual - Manual (Page 407)

D.2 National Limitations
D.2.1 Arithmetic Operators
D-5
Format for EXPRESSION Instruction
AppD
D.2 National Limitations
Several limitations apply when combining operands and operators to form numeric expressions. An expression is not
recognized as a numeric expression unless it meets these conditions.
This section describes these limitations.
D.2.1 Arithmetic Operators
These operators can be used with integer and real number operands. The unary minus operator can be used only once.
Bit operations can be performed only on integer data. Bit operands cannot be used for arithmetic operations. No auto-
matic data type conversion is performed even if the calculation result exceeds the range of the assigned register. There-
fore, the user must assign the appropriate data type to the variable.
D.2.2 Comparison Operators
These operators can be used with integer and real number operands. The left side must be a bit data register. To use an
integer bit operand in a comparison operation with the == or != operator, compare it with TRUE or FALSE.
D.2.3 Logic Operators
These operators can be used with bit operands.
MW00001 = MW00002 + MW00003 OK
MW00001 = MW00002 / 345 OK
MF00002 = (MW00004 + MF00002) / (ML00018 + MW00008) OK
MW00001 = MW00002 & 4096 OK
MB000010 = MB000011 - MB000012 NG
MW00001 = MB000011 * MW00001 NG
EXAMPLE
MB000010 = MW00002 != MW00003 OK
MB000010 = MF00002 < 99.99 OK
MB000010 = MW00002 >= MW00003 OK
MB000010 = MB000011 == true OK
MB000010 = MB000011 != 0 NG
MB000010 = MB000011 == 1 NG
EXAMPLE
MB000010 = MB000011 && MB000012 OK
MB000010 = !MB000011 OK
MB000010 = (MW000020 >= 50) && MB000011 OK
MB000010 = MW00001 || MW00002 NG
MB000010 = !MW00001 NG
EXAMPLE