ISPSoft User Manual

Chapter 11 Structured Text
Example 6: Examples of incorrect use of the assignment structure are as follows.
Statement
Description
The data type of one operand must not be different from the
D0 := M0 ;
data type of the other operand.
The data length of the operand at the left side of := must not
V_WORD := V_DWORD ; be less than the data length of the operand at the right side
of :=.
The value of a symbol whose data type is REAL can not be
D0 := V_REAL ;
assigned to a D device.
If one operand is a symbol whose data type is REAL, the
other operand must be a symbol whose data type is REAL.
V_LREAL := V_REAL ;
If one operand is a symbol whose data type is LREAL, the
other operand must be a symbol whose data type is LREAL.
The value of a symbol whose data type is TIMER can not be
V_DWORD := V_TIMER ; assigned to a symbol whose data type is DWORD, but can
be assigned to a symbol whose data type is WORD.
The value in a HC device can not be assigned to a symbol
V_WORD := HC0 ; whose data type is WORD, but can be assigned to a symbol
whose data type is DWORD.
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