lib/sema.txt
author Edouard Tisserant
Tue, 09 Jul 2019 08:31:02 +0200
changeset 1088 9cb7c8bf7dbc
parent 251 5e7457efbb8f
permissions -rw-r--r--
Add a column to VARIABLES.CSV, containing variable (derived) type name, additionally to current last column contyaining base type name
(*
 * (c) 2011 Edouard Tisserant
 *
 * Fake semaphore support, for non preemptive implementation.
 *
 *)


FUNCTION_BLOCK SEMA
  VAR_INPUT
    CLAIM : BOOL;
    RELEASE : BOOL;
  END_VAR
  VAR_OUTPUT
    BUSY : BOOL;
  END_VAR
  VAR
    Q_INTERNAL : BOOL;
  END_VAR

  Q_INTERNAL := CLAIM OR ( Q_INTERNAL AND (NOT RELEASE));
  BUSY := Q_INTERNAL;

END_FUNCTION_BLOCK