diff -r 3dd564ff94e4 -r f81527b1287b lib/iec_std_lib.h
--- a/lib/iec_std_lib.h	Fri Mar 28 10:06:20 2008 +0100
+++ b/lib/iec_std_lib.h	Thu Apr 03 18:28:10 2008 +0200
@@ -196,16 +196,16 @@
 } __IL_DEFVAR_T;
 
 typedef struct {
-  char state;     // current step state. 0 : inative, 1: active
-  char prev_state;  // previous step state. 0 : inative, 1: active
+  BOOL state;     // current step state. 0 : inative, 1: active
+  BOOL prev_state;  // previous step state. 0 : inative, 1: active
   TIME elapsed_time;  // time since step is active
 } STEP;
 
 typedef struct {
-  char stored;  // action storing state. 0 : not stored, 1: stored
-  char state; // current action state. 0 : inative, 1: active
-  char set;   // set have been requested (reset each time the body is evaluated)
-  char reset; // reset have been requested (reset each time the body is evaluated)
+  BOOL stored;  // action storing state. 0 : not stored, 1: stored
+  BOOL state; // current action state. 0 : inative, 1: active
+  BOOL set;   // set have been requested (reset each time the body is evaluated)
+  BOOL reset; // reset have been requested (reset each time the body is evaluated)
   TIME set_remaining_time;    // time before set will be requested
   TIME reset_remaining_time;  // time before reset will be requested
 } ACTION;