SEL

Binary selection — selects one of two inputs based on a Boolean selector.

Signature

     ┌─────────┐
  G ─┤         │
IN0 ─┤   SEL   ├─ OUT
IN1 ─┤         │
     └─────────┘

FUNCTION SEL : ANY
  VAR_INPUT
    G   : BOOL;
    IN0 : ANY;
    IN1 : ANY;
  END_VAR
END_FUNCTION

The return type matches the type of IN0 and IN1, which must be the same. SEL is polymorphic over any data type.

Inputs

Name

Type

Description

G

BOOL

Selector. FALSE selects IN0; TRUE selects IN1.

IN0

ANY

Value returned when G is FALSE.

IN1

ANY

Value returned when G is TRUE.

Outputs

Name

Type

Description

Return value

ANY

IN0 if G is FALSE, IN1 if G is TRUE. Same type as IN0 and IN1.

Description

SEL(G, IN0, IN1) returns IN0 if G is FALSE, or IN1 if G is TRUE. The types of IN0 and IN1 must be the same, and the return type matches the input type.

This function is polymorphic: it works with any data type for the selected inputs.

Example

result := SEL(TRUE, 10, 20);     (* result = 20 *)
result := SEL(FALSE, 10, 20);    (* result = 10 *)

See Also

  • MUX — multiplexer (selects from multiple inputs)

  • MAX — maximum of two values

  • MIN — minimum of two values

References