diff --git a/tgt-vvp/vvp_scope.c b/tgt-vvp/vvp_scope.c
index 03e0dc149..de362ed80 100644
--- a/tgt-vvp/vvp_scope.c
+++ b/tgt-vvp/vvp_scope.c
@@ -17,7 +17,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #if !defined(WINNT)
-#ident "$Id: vvp_scope.c,v 1.56 2001/11/01 04:26:57 steve Exp $"
+#ident "$Id: vvp_scope.c,v 1.57 2001/12/06 03:31:24 steve Exp $"
 #endif
 
 # include  "vvp_priv.h"
@@ -427,6 +427,21 @@ static void draw_net_in_scope(ivl_signal_t sig)
       free(args);
 }
 
+static void draw_delay(ivl_net_logic_t lptr)
+{
+      unsigned d0 = ivl_logic_delay(lptr, 0);
+      unsigned d1 = ivl_logic_delay(lptr, 1);
+      unsigned d2 = ivl_logic_delay(lptr, 2);
+      
+      if (d0 == 0 && d1 == 0 && d2 == 0)
+	    return;
+
+      if (d0 == d1 && d1 == d2)
+	    fprintf(vvp_out, " (%d)", d0);
+      else
+	    fprintf(vvp_out, " (%d,%d,%d)", d0, d1, d2);
+}
+
 static void draw_udp_def(ivl_udp_t udp)
 {
   unsigned init;
@@ -491,6 +506,7 @@ static void draw_udp_in_scope(ivl_net_logic_t lptr)
 	  vvp_mangle_id(ivl_logic_name(lptr)));
   fprintf(vvp_out, " UDP_%s", 
 	  vvp_mangle_id(ivl_udp_name(udp)));
+  draw_delay(lptr);
   
   for (pdx = 1 ;  pdx < ivl_logic_pins(lptr) ;  pdx += 1) 
     {
@@ -636,10 +652,12 @@ static void draw_logic_in_scope(ivl_net_logic_t lptr)
 				vvp_mangle_id(ivl_logic_name(lptr)),
 				level, inst,
 				lcasc);
-		  else
+		  else {
 			fprintf(vvp_out, "L_%s .functor %s", 
 				vvp_mangle_id(ivl_logic_name(lptr)),
 				ltype);
+			draw_delay(lptr);
+		  }
 		  for (pdx = inst; pdx < ninp && pdx < inst+4 ; pdx += 1) {
 			if (level) {
 			      fprintf(vvp_out, ", L_%s/%d/%d",
@@ -1217,6 +1235,10 @@ int draw_scope(ivl_scope_t net, ivl_scope_t parent)
 
 /*
  * $Log: vvp_scope.c,v $
+ * Revision 1.57  2001/12/06 03:31:24  steve
+ *  Support functor delays for gates and UDP devices.
+ *  (Stephan Boettcher)
+ *
  * Revision 1.56  2001/11/01 04:26:57  steve
  *  Generate code for deassign and cassign.
  *
diff --git a/vvp/arith.cc b/vvp/arith.cc
index 7f1841cd2..0f2317089 100644
--- a/vvp/arith.cc
+++ b/vvp/arith.cc
@@ -17,7 +17,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #if !defined(WINNT)
-#ident "$Id: arith.cc,v 1.20 2001/11/07 03:34:41 steve Exp $"
+#ident "$Id: arith.cc,v 1.21 2001/12/06 03:31:24 steve Exp $"
 #endif
 
 # include  "arith.h"
@@ -36,7 +36,7 @@ void vvp_arith_::output_x_(vvp_ipoint_t base, bool push, unsigned val)
 	    vvp_ipoint_t ptr = ipoint_index(base,idx);
 	    functor_t obj = functor_index(ptr);
 	    
-	    obj->put_oval(push, val);
+	    obj->put_oval(val, push);
       }
 }
 
@@ -49,7 +49,7 @@ void vvp_arith_::output_val_(vvp_ipoint_t base, bool push, unsigned long sum)
 	    unsigned val = sum & 1;
 	    sum >>= 1;
 	    
-	    obj->put_oval(push, val);
+	    obj->put_oval(val, push);
       }
 }
 
@@ -79,7 +79,7 @@ void vvp_wide_arith_::output_val_(vvp_ipoint_t base, bool push)
 		  page += 1;
 	    }
 
-	    obj->put_oval(push, val);
+	    obj->put_oval(val, push);
       }
 }
 
@@ -213,7 +213,7 @@ void vvp_arith_mult::wide(vvp_ipoint_t base, bool push)
 
 	    unsigned val = sum[idx];
 
-	    obj->put_oval(push, val);
+	    obj->put_oval(val, push);
       }
 
       delete[]sum;
@@ -369,7 +369,7 @@ void vvp_cmp_ge::set(vvp_ipoint_t i, bool push, unsigned val, unsigned)
 	    }
       }
 
-      put_oval(push, out_val);
+      put_oval(out_val, push);
 }
 
 void vvp_cmp_gt::set(vvp_ipoint_t i, bool push, unsigned val, unsigned)
@@ -403,7 +403,7 @@ void vvp_cmp_gt::set(vvp_ipoint_t i, bool push, unsigned val, unsigned)
 	    }
       }
 
-      put_oval(push, out_val);
+      put_oval(out_val, push);
 }
 
 
@@ -442,7 +442,7 @@ void vvp_shiftl::set(vvp_ipoint_t i, bool push, unsigned val, unsigned)
 	    for (unsigned idx = 0 ;  idx < amount ;  idx += 1) {
 		  optr = ipoint_index(base, idx);
 		  ofp = functor_index(optr);
-		  ofp->put_oval(push, 0);
+		  ofp->put_oval(0, push);
 	    }
 
 	    for (unsigned idx = amount ;  idx < wid_ ;  idx += 1) {
@@ -451,7 +451,7 @@ void vvp_shiftl::set(vvp_ipoint_t i, bool push, unsigned val, unsigned)
 		  iptr = ipoint_index(base, idx - amount);
 		  ifp = functor_index(iptr);
 
-		  ofp->put_oval(push, ifp->ival & 3);
+		  ofp->put_oval(ifp->ival & 3, push);
 	    }
       }
 }
@@ -494,13 +494,13 @@ void vvp_shiftr::set(vvp_ipoint_t i, bool push, unsigned val, unsigned)
 		  iptr = ipoint_index(base, idx + amount);
 		  ifp = functor_index(iptr);
 
-		  ofp->put_oval(push, ifp->ival & 3);
+		  ofp->put_oval(ifp->ival & 3, push);
 	    }
 
 	    for (unsigned idx = wid_-amount; idx < wid_ ;  idx += 1) {
 		  optr = ipoint_index(base, idx);
 		  ofp = functor_index(optr);
-		  ofp->put_oval(push, 0);
+		  ofp->put_oval(0, push);
 	    }
       }
 }
@@ -508,6 +508,10 @@ void vvp_shiftr::set(vvp_ipoint_t i, bool push, unsigned val, unsigned)
 
 /*
  * $Log: arith.cc,v $
+ * Revision 1.21  2001/12/06 03:31:24  steve
+ *  Support functor delays for gates and UDP devices.
+ *  (Stephan Boettcher)
+ *
  * Revision 1.20  2001/11/07 03:34:41  steve
  *  Use functor pointers where vvp_ipoint_t is unneeded.
  *
diff --git a/vvp/bufif.cc b/vvp/bufif.cc
index 0390e5e95..84a93e2e7 100644
--- a/vvp/bufif.cc
+++ b/vvp/bufif.cc
@@ -17,7 +17,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #if !defined(WINNT)
-#ident "$Id: bufif.cc,v 1.3 2001/11/07 03:34:42 steve Exp $"
+#ident "$Id: bufif.cc,v 1.4 2001/12/06 03:31:24 steve Exp $"
 #endif
 
 # include  "bufif.h"
@@ -80,11 +80,15 @@ void vvp_bufif1_s::set(vvp_ipoint_t ptr, bool push, unsigned v, unsigned)
 	    break;
       }
 
-      put_ostr(push, val, str);
+      put_ostr(val, str, push);
 }
 
 /*
  * $Log: bufif.cc,v $
+ * Revision 1.4  2001/12/06 03:31:24  steve
+ *  Support functor delays for gates and UDP devices.
+ *  (Stephan Boettcher)
+ *
  * Revision 1.3  2001/11/07 03:34:42  steve
  *  Use functor pointers where vvp_ipoint_t is unneeded.
  *
diff --git a/vvp/compile.cc b/vvp/compile.cc
index b7364f01a..e80e56632 100644
--- a/vvp/compile.cc
+++ b/vvp/compile.cc
@@ -17,7 +17,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #if !defined(WINNT)
-#ident "$Id: compile.cc,v 1.114 2001/11/07 03:34:42 steve Exp $"
+#ident "$Id: compile.cc,v 1.115 2001/12/06 03:31:24 steve Exp $"
 #endif
 
 # include  "arith.h"
@@ -579,7 +579,7 @@ static vvp_ipoint_t make_const_functor(unsigned val,
       functor_t obj = new const_functor_s(str0, str1);
       functor_define(fdx, obj);
 
-      obj->put_oval(false, val);
+      obj->put_oval(val, false);
 
       return fdx;
 }
@@ -929,6 +929,7 @@ char **compile_udp_table(char **table, char *row)
 }
 
 void compile_udp_functor(char*label, char*type,
+			 vvp_delay_t delay,
 			 unsigned argc, struct symb_s*argv)
 {
       struct vvp_udp_s *u = udp_find(type);
@@ -951,11 +952,13 @@ void compile_udp_functor(char*label, char*type,
 	    }
       }
 
+      udp->delay = delay;
+
       inputs_connect(fdx, argc, argv);
       free(argv);
       
       if (u->sequ)
-	    udp->put_oval(false, u->init);
+	    udp->put_oval(u->init, false);
 }
 
 
@@ -1341,6 +1344,10 @@ vvp_ipoint_t debug_lookup_functor(const char*name)
 
 /*
  * $Log: compile.cc,v $
+ * Revision 1.115  2001/12/06 03:31:24  steve
+ *  Support functor delays for gates and UDP devices.
+ *  (Stephan Boettcher)
+ *
  * Revision 1.114  2001/11/07 03:34:42  steve
  *  Use functor pointers where vvp_ipoint_t is unneeded.
  *
diff --git a/vvp/compile.h b/vvp/compile.h
index c13585a8b..3716e69e3 100644
--- a/vvp/compile.h
+++ b/vvp/compile.h
@@ -19,7 +19,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #if !defined(WINNT)
-#ident "$Id: compile.h,v 1.37 2001/11/06 03:07:22 steve Exp $"
+#ident "$Id: compile.h,v 1.38 2001/12/06 03:31:24 steve Exp $"
 #endif
 
 # include  <stdio.h>
@@ -73,6 +73,7 @@ extern void compile_vpi_time_precision(long pre);
  * to existing functors to manage the linking.
  */
 extern void compile_functor(char*label, char*type,
+			    vvp_delay_t delay,
 			    unsigned argc, struct symb_s*argv);
 
 
@@ -128,6 +129,7 @@ extern void compile_udp_def(int sequ, char*label, char *name,
 			    unsigned nin, unsigned init, char **table);
 
 extern void compile_udp_functor(char*label, char*type,
+				vvp_delay_t delay,
 				unsigned argc, struct symb_s*argv);
 
 extern char **compile_udp_table(char **table, char *row);
@@ -220,6 +222,10 @@ extern void compile_net(char*label, char*name,
 
 /*
  * $Log: compile.h,v $
+ * Revision 1.38  2001/12/06 03:31:24  steve
+ *  Support functor delays for gates and UDP devices.
+ *  (Stephan Boettcher)
+ *
  * Revision 1.37  2001/11/06 03:07:22  steve
  *  Code rearrange. (Stephan Boettcher)
  *
diff --git a/vvp/delay.h b/vvp/delay.h
index edeba7112..305965ae0 100644
--- a/vvp/delay.h
+++ b/vvp/delay.h
@@ -19,9 +19,11 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #if !defined(WINNT)
-#ident "$Id: delay.h,v 1.1 2001/11/10 18:07:11 steve Exp $"
+#ident "$Id: delay.h,v 1.2 2001/12/06 03:31:24 steve Exp $"
 #endif
 
+#include "pointers.h"
+
 /*
 **  vvp_delay_t del;
 **
@@ -61,8 +63,6 @@
 **         tgt and src are deleted.
 */
 
-typedef struct vvp_delay_s *vvp_delay_t;
-
 struct vvp_delay_s {
       vvp_delay_s(unsigned);
       unsigned delay(unsigned char idx) { return del[tab[idx]]; }
@@ -113,6 +113,10 @@ vvp_delay_t vvp_delay_set(vvp_delay_t tgt, vvp_delay_t src,
 
 /*
 ** $Log: delay.h,v $
+** Revision 1.2  2001/12/06 03:31:24  steve
+**  Support functor delays for gates and UDP devices.
+**  (Stephan Boettcher)
+**
 ** Revision 1.1  2001/11/10 18:07:11  steve
 **  Runtime support for functor delays. (Stephan Boettcher)
 **
diff --git a/vvp/force.cc b/vvp/force.cc
index 6941d3ea9..22d0678ad 100644
--- a/vvp/force.cc
+++ b/vvp/force.cc
@@ -18,7 +18,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #if !defined(WINNT)
-#ident "$Id: force.cc,v 1.3 2001/11/07 03:34:42 steve Exp $"
+#ident "$Id: force.cc,v 1.4 2001/12/06 03:31:24 steve Exp $"
 #endif
 
 # include  "codes.h"
@@ -35,41 +35,29 @@ inline bool functor_s::disable(vvp_ipoint_t ptr)
 
 inline bool functor_s::enable(vvp_ipoint_t ptr)
 {
-      unsigned val;
-      if (ostr == 0)
-	    val = 3;
-      else switch (ostr & 0x88) {
-	  case 0x00: val = 0; break;
-	  case 0x88: val = 1; break;
-	  default:   val = 2;
-      }
-      if (val != oval) {
-	    oval = val;
-	    propagate(true);
-      }
       bool r = inhibit;
       inhibit = 0;
+      if (r) {
+	    if (get_str() != get_ostr())
+		  propagate();
+	    else
+		  assert(get() == get_oval());
+      }
       return r;
 }
 
-inline void functor_s::force(unsigned val, unsigned str)
+void force_functor_s::set(vvp_ipoint_t i, bool push, 
+			  unsigned val, unsigned str)
 {
-      if (ostr != str  ||  oval != val) {
-	    unsigned save = ostr;
+      if (ipoint_port(i) == 0) {
 	    oval = val;
 	    ostr = str;
-	    propagate(true);
-	    ostr = save;
-      }
-}
-
-void force_functor_s::set(vvp_ipoint_t i, bool, unsigned val, unsigned str)
-{
-      put(i, val);
-      if (ipoint_port(i) == 0) {
-	    if (active  && out) {
+	    if (active && out) {
 		  functor_t tgt = functor_index(out);
-		  tgt->force(ival&3, get_ostr());
+		  if (str != tgt->get_str())
+			tgt->propagate(val, str, push);
+		  else
+			assert(val == tgt->get());
 	    }
       }
 }
@@ -123,7 +111,7 @@ bool of_FORCE(vthread_t thr, vvp_code_t cp)
 	    fofu->port[3] = tgt->out;
 	    tgt->out = ipoint_make(ifofu, 3);
 
-	    fofu->set(ifofu, false, fofu->ival&3, fofu->get_ostr());
+	    fofu->set(ifofu, false, fofu->get_oval(), fofu->get_ostr());
       }
 
       return true;
@@ -136,7 +124,6 @@ bool of_RELEASE(vthread_t thr, vvp_code_t cp)
 
       if (release_force(itgt, tgt))
 	    tgt->enable(itgt);
-      // bug:  a strength change will not be propagated.
 
       return true;
 }
@@ -158,7 +145,7 @@ void var_functor_s::set(vvp_ipoint_t ptr, bool push, unsigned val, unsigned)
       unsigned pp = ipoint_port(ptr);
       
       if (assigned() && pp==1  ||  !assigned() && pp==0) {
-	    put_oval(push, val);
+	    put_oval(val, push);
       }
 }
 
@@ -249,6 +236,10 @@ bool of_DEASSIGN(vthread_t thr, vvp_code_t cp)
 
 /*
  * $Log: force.cc,v $
+ * Revision 1.4  2001/12/06 03:31:24  steve
+ *  Support functor delays for gates and UDP devices.
+ *  (Stephan Boettcher)
+ *
  * Revision 1.3  2001/11/07 03:34:42  steve
  *  Use functor pointers where vvp_ipoint_t is unneeded.
  *
diff --git a/vvp/functor.cc b/vvp/functor.cc
index 183c07f1f..ee1033a54 100644
--- a/vvp/functor.cc
+++ b/vvp/functor.cc
@@ -17,7 +17,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #if !defined(WINNT)
-#ident "$Id: functor.cc,v 1.34 2001/11/16 04:22:27 steve Exp $"
+#ident "$Id: functor.cc,v 1.35 2001/12/06 03:31:24 steve Exp $"
 #endif
 
 # include  "functor.h"
@@ -114,10 +114,12 @@ functor_s::functor_s()
       port[2] = 0;
       port[3] = 0;
       ival = 0xaa;
+      cval = 2;
       oval = 2;
       odrive0 = 6;
       odrive1 = 6;
       ostr = StX;
+      cstr = StX;
       inhibit = 0;
 #if defined(WITH_DEBUG)
       breakpoint = 0;
@@ -169,6 +171,10 @@ edge_inputs_functor_s::~edge_inputs_functor_s()
 
 /*
  * $Log: functor.cc,v $
+ * Revision 1.35  2001/12/06 03:31:24  steve
+ *  Support functor delays for gates and UDP devices.
+ *  (Stephan Boettcher)
+ *
  * Revision 1.34  2001/11/16 04:22:27  steve
  *  include stdlib.h for portability.
  *
diff --git a/vvp/functor.h b/vvp/functor.h
index 2bc4797f2..38028f586 100644
--- a/vvp/functor.h
+++ b/vvp/functor.h
@@ -19,19 +19,12 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #if !defined(WINNT)
-#ident "$Id: functor.h,v 1.39 2001/11/10 18:07:12 steve Exp $"
+#ident "$Id: functor.h,v 1.40 2001/12/06 03:31:24 steve Exp $"
 #endif
 
 # include  "pointers.h"
 # include  "delay.h"
 
-/*
- * Create a propagation event. The fun parameter points to the functor
- * to have its output propagated, and the delay is the delay to
- * schedule the propagation.
- */
-extern void schedule_functor(functor_t fun, unsigned delay);
-
 /*
  * The vvp_ipoint_t is an integral type that is 32bits. The low 2 bits
  * select the port of the referenced functor, and the remaining 30
@@ -68,7 +61,7 @@ extern void schedule_functor(functor_t fun, unsigned delay);
  *    STRONG = 6,
  *    SUPPLY = 7
  *
- * The output value (oval) is combined with the drive specifications
+ * The output value (cval) is combined with the drive specifications
  * to make a fully strength aware output, as described below.
  *
  * OUTPUT STRENGTHS:
@@ -81,9 +74,9 @@ extern void schedule_functor(functor_t fun, unsigned delay);
  * strength-value closest to supply0.
  *
  * The functor calculates, when it operates, a 4-value output into
- * oval and a fully strength aware value into ostr. The mode-0
- * functors use the odrive0 and odrive1 fields to form the strength
- * value.
+ * oval and a fully strength aware value into ostr.  Functors with
+ * fixed drive strength use the odrive0 and odrive1 fields to form the
+ * strength value.  
  */
 
 /*
@@ -163,14 +156,19 @@ struct functor_s {
 
     private:
 	/* Output value (low bits) and drive1 and drive0 strength. */
-      unsigned oval       : 2;
+      unsigned cval       : 2;
     protected:
       unsigned odrive0    : 3;
       unsigned odrive1    : 3;
     private:
 	/* Strength form of the output value. */
+      unsigned cstr       : 8;
+      
+    protected:
       unsigned ostr       : 8;
+      unsigned oval       : 2;
 
+    private:
       unsigned inhibit    : 1;
 
     public:
@@ -178,18 +176,24 @@ struct functor_s {
         /* True if this functor triggers a breakpoint. */
       unsigned breakpoint : 1;
 #endif
+
+    public:
       virtual void set(vvp_ipoint_t ipt, bool push, 
 		       unsigned val, unsigned str = 0) = 0;
 
-      inline unsigned char get() { return oval; }
+      inline unsigned char get()      { return cval; }
+      inline unsigned char get_str()  { return cstr; }
+      inline unsigned char get_oval() { return oval; }
       inline unsigned char get_ostr() { return ostr; }
+
       void put(vvp_ipoint_t ipt, unsigned val);
-      void put_oval(bool push, unsigned val);
-      void put_ostr(bool push, unsigned val, unsigned str);
+      void put_oval(unsigned val, bool push = true);
+      void put_ostr(unsigned val, unsigned str, bool push = true);
+      void schedule(unsigned delay);
       bool disable(vvp_ipoint_t ptr);
       bool enable(vvp_ipoint_t ptr);
-      void propagate(bool push);
-      void force(unsigned val, unsigned str);
+      void propagate(bool push = true);
+      void propagate(unsigned val, unsigned str, bool push = true);
 };
 
 /*
@@ -204,63 +208,72 @@ inline void functor_s::put(vvp_ipoint_t ptr, unsigned val)
       ival = (ival & imask) | ((val & 3) << (2*pp));
 }
 
-inline void functor_s::propagate(bool push)
+inline void functor_s::propagate(unsigned val, unsigned str, bool push)
 {
+      cval = val;
+      cstr = str;
       vvp_ipoint_t idx = out;
       while (idx) {
 	    functor_t idxp = functor_index(idx);
-	    idxp->set(idx, push, oval, ostr);
+	    idxp->set(idx, push, val, str);
 	    idx = idxp->port[ipoint_port(idx)];
-	    
-#if defined(WITH_DEBUG)
-	    if (fp->breakpoint)
-		  breakpoint();
-#endif
       }
+
+#if defined(WITH_DEBUG)
+      if (breakpoint)
+	    breakpoint();
+#endif
 }
 
-inline void functor_s::put_ostr(bool push, unsigned val, unsigned str)
+inline void functor_s::propagate(bool push)
 {
-      if (val != oval || str != ostr) {
+      propagate(get_oval(), get_ostr(), push);
+}
 
+inline void functor_s::put_ostr(unsigned val, unsigned str, bool push)
+{
+      if (str != get_ostr() || val != get_oval()) {
+
+	    unsigned char ooval = oval;
 	    ostr = str;
+	    oval = val;
 
 	    if (inhibit)
 		  return;
 
-	    oval = val;
-
 	    unsigned del;
 	    if (delay)
-	      del = vvp_delay_get(delay, oval, val);
+	      del = vvp_delay_get(delay, ooval, val);
 	    else
 	      del = 0;
 
-	    if (del == 0  &&  push)
-		  propagate(true);
+	    if (push && del == 0) {
+		  propagate();
+	    }
 	    else
-		  schedule_functor(this, del);
+		  schedule(del);
       }
 }
 
-inline void functor_s::put_oval(bool push, unsigned val)
+inline void functor_s::put_oval(unsigned val, bool push)
 {
+      unsigned char str;
       switch (val) {
 	  case 0:
-	    ostr = 0x00 | (odrive0<<0) | (odrive0<<4);
+	    str = 0x00 | (odrive0<<0) | (odrive0<<4);
 	    break;
 	  case 1:
-	    ostr = 0x88 | (odrive1<<0) | (odrive1<<4);
+	    str = 0x88 | (odrive1<<0) | (odrive1<<4);
 	    break;
 	  case 2:
-	    ostr = 0x80 | (odrive0<<0) | (odrive1<<4);
+	    str = 0x80 | (odrive0<<0) | (odrive1<<4);
 	    break;
-	  case 3:
-	    ostr = 0x00;
+	  default:
+	    str = 0x00;
 	    break;
       }
 
-      put_ostr(push, val, ostr);
+      put_ostr(val, str, push);
 }
 
 /*
@@ -280,7 +293,7 @@ inline void functor_s::put_oval(bool push, unsigned val)
  * propagation events to pass the output on.
  */
 inline static 
-void functor_set(vvp_ipoint_t ptr, unsigned val, unsigned str, bool push)
+void functor_set(vvp_ipoint_t ptr, unsigned val, unsigned str, bool push = true)
 {
       functor_t fp = functor_index(ptr);
       fp->set(ptr, push, val, str);
@@ -302,20 +315,6 @@ unsigned functor_get(vvp_ipoint_t ptr)
       return fp->get();
 }
 
-
-/*
- * When a propagation event happens, this function is called with the
- * address of the affected functor. It propagates the output to all
- * the inputs it is connected to, creating new propagation event on
- * the way.
- */
-inline static
-void functor_propagate(functor_t fp, bool push=true)
-{
-      fp->propagate(push);
-}
-
-
 //          Special infrastructure functor types
 
 
@@ -376,6 +375,10 @@ extern vvp_fvector_t vvp_fvector_continuous_new(unsigned size, vvp_ipoint_t p);
 
 /*
  * $Log: functor.h,v $
+ * Revision 1.40  2001/12/06 03:31:24  steve
+ *  Support functor delays for gates and UDP devices.
+ *  (Stephan Boettcher)
+ *
  * Revision 1.39  2001/11/10 18:07:12  steve
  *  Runtime support for functor delays. (Stephan Boettcher)
  *
diff --git a/vvp/logic.cc b/vvp/logic.cc
index 498fbcf99..ec623f893 100644
--- a/vvp/logic.cc
+++ b/vvp/logic.cc
@@ -17,7 +17,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #if !defined(WINNT)
-#ident "$Id: logic.cc,v 1.3 2001/11/16 04:22:27 steve Exp $"
+#ident "$Id: logic.cc,v 1.4 2001/12/06 03:31:24 steve Exp $"
 #endif
 
 # include  "logic.h"
@@ -53,7 +53,7 @@ void table_functor_s::set(vvp_ipoint_t ptr, bool push, unsigned v, unsigned)
       val >>= 2 * (ival&0x03);
       val &= 0x03;
 
-      put_oval(push, val);
+      put_oval(val, push);
 }
 
 /*
@@ -62,7 +62,9 @@ void table_functor_s::set(vvp_ipoint_t ptr, bool push, unsigned v, unsigned)
  * functor. Also resolve the inputs to the functor.
  */
 
-void compile_functor(char*label, char*type, unsigned argc, struct symb_s*argv)
+void compile_functor(char*label, char*type,
+		     vvp_delay_t delay,
+		     unsigned argc, struct symb_s*argv)
 {
       functor_t obj;
 
@@ -130,6 +132,8 @@ void compile_functor(char*label, char*type, unsigned argc, struct symb_s*argv)
       define_functor_symbol(label, fdx);
       free(label);
 
+      obj->delay = delay;
+
       inputs_connect(fdx, argc, argv);
       free(argv);
 }
@@ -137,6 +141,10 @@ void compile_functor(char*label, char*type, unsigned argc, struct symb_s*argv)
 
 /*
  * $Log: logic.cc,v $
+ * Revision 1.4  2001/12/06 03:31:24  steve
+ *  Support functor delays for gates and UDP devices.
+ *  (Stephan Boettcher)
+ *
  * Revision 1.3  2001/11/16 04:22:27  steve
  *  include stdlib.h for portability.
  *
diff --git a/vvp/memory.cc b/vvp/memory.cc
index 0a70f3899..7c7e0498a 100644
--- a/vvp/memory.cc
+++ b/vvp/memory.cc
@@ -18,7 +18,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #if !defined(WINNT)
-#ident "$Id: memory.cc,v 1.13 2001/11/07 03:34:42 steve Exp $"
+#ident "$Id: memory.cc,v 1.14 2001/12/06 03:31:24 steve Exp $"
 #endif
 
 #include "memory.h"
@@ -317,7 +317,7 @@ void update_data(vvp_memory_port_t data)
       vvp_ipoint_t dx = ipoint_index(data->ix, i);
       functor_t df = functor_index(dx);
       unsigned char out = get_bit(data->cur_bits, i + data->bitoff);
-      df->put_oval(false, out);
+      df->put_oval(out);
     }
 }
 
@@ -338,7 +338,7 @@ void update_data_ports(vvp_memory_t mem, vvp_memory_bits_t bits, int bit,
 	    {
 	      vvp_ipoint_t ix = ipoint_index(a->ix, i);
 	      functor_t df = functor_index(ix);
-	      df->put_oval(false, val);
+	      df->put_oval(val);
 	    }
 	}
       a = a->next;
diff --git a/vvp/npmos.cc b/vvp/npmos.cc
index 52cc2419a..1d3108dbe 100644
--- a/vvp/npmos.cc
+++ b/vvp/npmos.cc
@@ -17,7 +17,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #if !defined(WINNT)
-#ident "$Id: npmos.cc,v 1.6 2001/11/07 03:34:42 steve Exp $"
+#ident "$Id: npmos.cc,v 1.7 2001/12/06 03:31:24 steve Exp $"
 #endif
 
 # include  "npmos.h"
@@ -58,10 +58,13 @@ void vvp_pmos_s::set(vvp_ipoint_t ptr, bool push, unsigned v, unsigned s)
       unsigned char val;
       unsigned char str;
 
-      if (in0 == 3 || in1 == 0) {
+      if (in1 == 0) {
 	    // gate on; output follows input
 	    val = in0;
 	    str = istr;
+      } else if (in0 == 3) {
+	    val = 3;
+	    str = HiZ;
       } else if (in1 == 2 || in1 == 3) {
 	    // gate X or Z; output is undefined
 	    val = 2;
@@ -82,11 +85,15 @@ void vvp_pmos_s::set(vvp_ipoint_t ptr, bool push, unsigned v, unsigned s)
 	    str = HiZ;
       }
 
-      put_ostr(push, val, str);
+      put_ostr(val, str, push);
 }
 
 /*
  * $Log: npmos.cc,v $
+ * Revision 1.7  2001/12/06 03:31:24  steve
+ *  Support functor delays for gates and UDP devices.
+ *  (Stephan Boettcher)
+ *
  * Revision 1.6  2001/11/07 03:34:42  steve
  *  Use functor pointers where vvp_ipoint_t is unneeded.
  *
diff --git a/vvp/parse.y b/vvp/parse.y
index 1b0cfc876..40bab74f8 100644
--- a/vvp/parse.y
+++ b/vvp/parse.y
@@ -19,11 +19,12 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #if !defined(WINNT)
-#ident "$Id: parse.y,v 1.40 2001/11/01 03:00:19 steve Exp $"
+#ident "$Id: parse.y,v 1.41 2001/12/06 03:31:25 steve Exp $"
 #endif
 
 # include  "parse_misc.h"
 # include  "compile.h"
+# include  "delay.h"
 # include  <stdio.h>
 # include  <stdlib.h>
 # include  <assert.h>
@@ -51,6 +52,8 @@ extern FILE*yyin;
 
       struct argv_s argv;
       vpiHandle vpi;
+
+      vvp_delay_t cdelay;
 };
 
 
@@ -79,6 +82,7 @@ extern FILE*yyin;
 
 %type <argv> argument_opt argument_list
 %type <vpi>  argument
+%type <cdelay> delay
 
 %%
 
@@ -117,13 +121,11 @@ statement
   /* Functor statements define functors. The functor must have a
      label and a type name, and may have operands. */
 
-	: T_LABEL K_FUNCTOR T_SYMBOL ',' symbols ';'
-		{ struct symbv_s obj = $5;
-		  compile_functor($1, $3, obj.cnt, obj.vect);
-		}
+	: T_LABEL K_FUNCTOR T_SYMBOL delay ',' symbols ';'
+		{ compile_functor($1, $3, $4, $6.cnt, $6.vect); }
 
-	| T_LABEL K_FUNCTOR T_SYMBOL','  T_NUMBER ';'
-		{ compile_functor($1, $3, 0, 0); }
+	| T_LABEL K_FUNCTOR T_SYMBOL delay ','  T_NUMBER ';'
+		{ compile_functor($1, $3, $4, 0, 0); }
 
 
   /* UDP statements define or instantiate UDPs.  Definitions take a 
@@ -136,8 +138,8 @@ statement
 	| T_LABEL K_UDP_C T_STRING ',' T_NUMBER ',' udp_table ';'
 		{ compile_udp_def(0, $1, $3, $5, 0, $7); }
 
-	| T_LABEL K_UDP T_SYMBOL ',' symbols ';'
-		{ compile_udp_functor($1, $3, $5.cnt, $5.vect); }
+	| T_LABEL K_UDP T_SYMBOL delay ',' symbols ';'
+		{ compile_udp_functor($1, $3, $4, $6.cnt, $6.vect); }
 
 
   /* Memory.  Definition, port, initialization */
@@ -495,6 +497,17 @@ o_komma
 	| ','
 	;
 
+delay
+	: /* empty */ 
+		{ $$ = 0; }
+	| '(' T_NUMBER ')'
+		{ $$ = new vvp_delay_2_s($2, $2); }
+	| '(' T_NUMBER ',' T_NUMBER ')'
+		{ $$ = new vvp_delay_2_s($2, $4); }
+	| '(' T_NUMBER ',' T_NUMBER ',' T_NUMBER ')'
+		{ $$ = new vvp_delay_3_s($2, $4, $6); }
+	;
+
 %%
 
 int compile_design(const char*path)
@@ -514,6 +527,10 @@ int compile_design(const char*path)
 
 /*
  * $Log: parse.y,v $
+ * Revision 1.41  2001/12/06 03:31:25  steve
+ *  Support functor delays for gates and UDP devices.
+ *  (Stephan Boettcher)
+ *
  * Revision 1.40  2001/11/01 03:00:19  steve
  *  Add force/cassign/release/deassign support. (Stephan Boettcher)
  *
diff --git a/vvp/pointers.h b/vvp/pointers.h
index 861b6bb5a..bf6bea943 100644
--- a/vvp/pointers.h
+++ b/vvp/pointers.h
@@ -19,7 +19,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #if !defined(WINNT)
-#ident "$Id: pointers.h,v 1.7 2001/11/07 03:34:42 steve Exp $"
+#ident "$Id: pointers.h,v 1.8 2001/12/06 03:31:25 steve Exp $"
 #endif
 
 /*
@@ -104,8 +104,17 @@ typedef struct vthread_s*vthread_t;
 
 typedef struct vvp_fvector_s *vvp_fvector_t;
 
+/* delay object */
+
+typedef struct vvp_delay_s *vvp_delay_t;
+
+
 /*
  * $Log: pointers.h,v $
+ * Revision 1.8  2001/12/06 03:31:25  steve
+ *  Support functor delays for gates and UDP devices.
+ *  (Stephan Boettcher)
+ *
  * Revision 1.7  2001/11/07 03:34:42  steve
  *  Use functor pointers where vvp_ipoint_t is unneeded.
  *
diff --git a/vvp/resolv.cc b/vvp/resolv.cc
index d5b87e5f3..2e06c1580 100644
--- a/vvp/resolv.cc
+++ b/vvp/resolv.cc
@@ -17,7 +17,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #if !defined(WINNT)
-#ident "$Id: resolv.cc,v 1.8 2001/11/07 03:34:42 steve Exp $"
+#ident "$Id: resolv.cc,v 1.9 2001/12/06 03:31:25 steve Exp $"
 #endif
 
 # include  "resolv.h"
@@ -164,11 +164,21 @@ void resolv_functor_s::set(vvp_ipoint_t i, bool push, unsigned, unsigned str)
       }
 
 	/* If the output changes, then create a propagation event. */
-      put_ostr(push, val, sval);
+
+      // Do not propagate (push).  Why?  Because if, for example, a
+      // clock buffer is modeled as parallel inverters, the output
+      // must not show 'bx transitions when the inverters all propagte
+      // at the same time.
+
+      put_ostr(val, sval, false);
 }
 
 /*
  * $Log: resolv.cc,v $
+ * Revision 1.9  2001/12/06 03:31:25  steve
+ *  Support functor delays for gates and UDP devices.
+ *  (Stephan Boettcher)
+ *
  * Revision 1.8  2001/11/07 03:34:42  steve
  *  Use functor pointers where vvp_ipoint_t is unneeded.
  *
diff --git a/vvp/schedule.cc b/vvp/schedule.cc
index 6df519b91..bcbad4727 100644
--- a/vvp/schedule.cc
+++ b/vvp/schedule.cc
@@ -17,7 +17,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #if !defined(WINNT)
-#ident "$Id: schedule.cc,v 1.13 2001/11/07 03:34:42 steve Exp $"
+#ident "$Id: schedule.cc,v 1.14 2001/12/06 03:31:25 steve Exp $"
 #endif
 
 # include  "schedule.h"
@@ -56,6 +56,7 @@ struct event_s {
       };
       unsigned val  :2;
       unsigned type :2;
+      // unsigned char str;
 
       struct event_s*next;
       struct event_s*last;
@@ -238,13 +239,15 @@ void schedule_vthread(vthread_t thr, unsigned delay)
       schedule_event_(cur);
 }
 
-void schedule_functor(functor_t funp, unsigned delay)
+void functor_s::schedule(unsigned delay)
 {
       struct event_s*cur = e_alloc();
 
       cur->delay = delay;
-      cur->funp = funp;
+      cur->funp = this;
       cur->type = TYPE_PROP;
+      // cur->str = get_ostr();
+      // cur->val = get_oval();
 
       schedule_event_(cur);
 }
@@ -320,23 +323,23 @@ void schedule_simulate(void)
 
 		case TYPE_PROP:
 		    //printf("Propagate %p\n", cur->fun);
-		  functor_propagate(cur->funp);
+		  cur->funp->propagate();
 		  e_free(cur);
 		  break;
 
 		case TYPE_ASSIGN:
 		  switch (cur->val) {
 		      case 0:
-			functor_set(cur->fun, cur->val, St0, false);
+			functor_set(cur->fun, cur->val, St0);
 			break;
 		      case 1:
-			functor_set(cur->fun, cur->val, St1, false);
+			functor_set(cur->fun, cur->val, St1);
 			break;
 		      case 2:
-			functor_set(cur->fun, cur->val, StX, false);
+			functor_set(cur->fun, cur->val, StX);
 			break;
 		      case 3:
-			functor_set(cur->fun, cur->val, HiZ, false);
+			functor_set(cur->fun, cur->val, HiZ);
 			break;
 		  }
 		  e_free(cur);
@@ -361,6 +364,10 @@ void schedule_simulate(void)
 
 /*
  * $Log: schedule.cc,v $
+ * Revision 1.14  2001/12/06 03:31:25  steve
+ *  Support functor delays for gates and UDP devices.
+ *  (Stephan Boettcher)
+ *
  * Revision 1.13  2001/11/07 03:34:42  steve
  *  Use functor pointers where vvp_ipoint_t is unneeded.
  *
diff --git a/vvp/udp.cc b/vvp/udp.cc
index 31ea30c0b..892bee321 100644
--- a/vvp/udp.cc
+++ b/vvp/udp.cc
@@ -18,7 +18,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #if !defined(WINNT)
-#ident "$Id: udp.cc,v 1.13 2001/11/07 03:34:42 steve Exp $"
+#ident "$Id: udp.cc,v 1.14 2001/12/06 03:31:25 steve Exp $"
 #endif
 
 #include "udp.h"
@@ -31,12 +31,12 @@
 #include <stdlib.h>
 #include <stdio.h>
 
-void udp_functor_s::set(vvp_ipoint_t i, bool, unsigned val, unsigned)
+void udp_functor_s::set(vvp_ipoint_t i, bool push, unsigned val, unsigned)
 {
   // old_ival is set on the way out
   put(i, val);
   unsigned char out = udp->propagate(this, i);
-  put_oval(false, out);
+  put_oval(out, push);
 }
 
 
@@ -350,6 +350,10 @@ void vvp_udp_s::compile_row_(udp_table_entry_t row, char *rchr)
 
 /*
  * $Log: udp.cc,v $
+ * Revision 1.14  2001/12/06 03:31:25  steve
+ *  Support functor delays for gates and UDP devices.
+ *  (Stephan Boettcher)
+ *
  * Revision 1.13  2001/11/07 03:34:42  steve
  *  Use functor pointers where vvp_ipoint_t is unneeded.
  *
diff --git a/vvp/vpi_signal.cc b/vvp/vpi_signal.cc
index db5c18ca8..eab11678f 100644
--- a/vvp/vpi_signal.cc
+++ b/vvp/vpi_signal.cc
@@ -17,7 +17,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #if !defined(WINNT)
-#ident "$Id: vpi_signal.cc,v 1.29 2001/11/07 03:34:42 steve Exp $"
+#ident "$Id: vpi_signal.cc,v 1.30 2001/12/06 03:31:25 steve Exp $"
 #endif
 
 /*
@@ -404,7 +404,7 @@ static void functor_poke(struct __vpiSignal*rfp, unsigned idx,
 {
       vvp_ipoint_t ptr = vvp_fvector_get(rfp->bits,idx);
       functor_t fu = functor_index(ptr);
-      fu->put_ostr(true, val, str);
+      fu->put_ostr(val, str, true);
 }
 
 static vpiHandle signal_put_value(vpiHandle ref, s_vpi_value*vp,
@@ -552,6 +552,10 @@ vpiHandle vpip_make_net(char*name, int msb, int lsb, bool signed_flag,
 
 /*
  * $Log: vpi_signal.cc,v $
+ * Revision 1.30  2001/12/06 03:31:25  steve
+ *  Support functor delays for gates and UDP devices.
+ *  (Stephan Boettcher)
+ *
  * Revision 1.29  2001/11/07 03:34:42  steve
  *  Use functor pointers where vvp_ipoint_t is unneeded.
  *