lib/sema.txt
author Edouard Tisserant
Fri, 19 Oct 2012 12:10:32 +0200
changeset 634 736b36a83548
parent 251 5e7457efbb8f
permissions -rw-r--r--
Added double curly braces for pragma (kept single curly braces for compatibility). Added macro def and undef surrounding pragma to simplify user code. Moved useless comment from generated code back to code generator.
(*
 * (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