Omron SYSMAC CX-Programmer 8.1, Руководство по эксплуатации

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Elements of SFC Section 2-3
51
Boolean Action (Bit)
Boolean Variable
A transition condition can be defined using a Boolean variable name.
Example: In the case of “bFlag”, the condition is met when “bFlag” is ON.
Actual Address (Bit)
A transition’s condition can be defined using an actual address (bit).
ST Expression
A transition condition can be defined using an ST expression.
Formats for ST-programmed condition equations are listed below:
Formats for Boolean Variables in Defining Transitions with ST Expressions
Operator
Name
Operator Example Details
Parenthesis () (a & b) OR c Condition met if both “a” and “b” are ON, or if
“c” is ON
Complement
NOT
NOT bFlag Condition met if bFlag is OFF
AND
AND, &
a & b Condition met if both “a” and “b” are ON
Exclusive OR
XOR
a XOR b Condition met if “a” differs from “b”
OR
OR
a OR b Condition met if “a” or “b” is ON
Equality
=
a = b Condition met if “a” and “b” are the same
Formats for INT, DINT, LINT, UINT, UDINT, ULINT, CHANNEL, REAL, LREAL, WORD,
DWORD, LWORD, UINT_BCD, UDINT_BCD, and ULINT_BCD Variables in Defining
Transitions with ST Expressions
Operator
Name Operator Example Details
Parenthesis () (nValue = 10) &
a Condition met if nValue is 10 and “a” is ON
Comparison
<, >, <=, >=
nValue >= 10 Condition met if nValue is 10 or greater
Equality
=
nValue = 10 Condition met if nValue is 10
Inequality
<>
nValue <> 10 Condition met if nValue is not 10
Transition Program
Program names may be used as transition conditions.
A transition program can be coded using either Ladder or ST as the language.
In CX-Programmer, a transition condition is met when the Boolean variable with the
same name as the transition program is switched to “ON”.
PRG
Any name
PRG a
Condition met if “a” is OFF
Transition Program Name
Example 1: “b” bit for “a”