diff --git a/tcl/drivers/trun.tcl b/tcl/drivers/trun.tcl
index 7390b86..6597218 100644
--- a/tcl/drivers/trun.tcl
+++ b/tcl/drivers/trun.tcl
@@ -447,7 +447,16 @@ proc trun::read_run {} {
   }
   if {$dblctrl} {
     if {[hval [sct]/dblctrl/mode] == 0} { # inactive -> stable
-      hupdate [sct]/dblctrl/mode 1
+      set tol [hvali [sct]/tolerance]
+      set tg [silent $tsample sct target]
+      if {$tg > $tsample + $tol} {
+         set dmode 2  ;# up
+      } elseif {$tg < $tsample - $tol} {
+         set dmode 3  ;# down
+      } else {
+         set dmode 1  ;# stable
+      }
+      hupdate [sct]/dblctrl/mode $dmode
     }
     set value $tsample
   } else {