2 flexlogic rules – GE Industrial Solutions Entellisys 5.0 User Manual User Manual

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FlexLogic rules

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11

The characteristics of the logic gates are found in Table 11-4.

The latch logic operation is described in Table 11-5.

11.2 FlexLogic rules

When forming a FlexLogic equation, the sequence in the linear array of parameters must follow
these general rules:

1. Operands must precede the operator that uses the operands as inputs.
2. Operators have only one output. The output of an operator must be used to create a virtual

output if it is to be used as an input to two or more operators.

3. Assigning the output of an operator to a virtual output terminates the equation.
4. A timer operator (e.g., “TIMER 1”) or virtual output assignment (e.g., “= Virtual Output 1”) may

only be used once. If this rule is broken, a syntax error is declared.

Table 11-4 Gate characteristics

GATES

NUMBER OF INPUTS

OUTPUT IS '1' (= ON) IF...

NOT

1

input is '0'

OR

2 to 16

any input is '1'

AND

2 to 16

all inputs are '1'

NOR

2 to 16

all inputs are '0'

NAND

2 to 16

any input is '0'

XOR

2

only one input is '1'

Table 11-5 Latch operation table

LATCH TYPE

LATCH SET

LATCH RESET

LATCH OUTPUT

Reset
Dominant

ON

OFF

ON

OFF

OFF

Previous State

ON

ON

OFF

OFF

ON

OFF

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