diff --git a/drawing/Common.lua b/drawing/Common.lua
index e99bab3..c64657c 100644
--- a/drawing/Common.lua
+++ b/drawing/Common.lua
@@ -2,8 +2,6 @@ local M = {}
 
 local Util = require 'Util'
 local Arc = require 'Arc'
-local Dial = require 'Dial'
-local CompoundDial = require 'CompoundDial'
 local Text = require 'Text'
 local CriticalText = require 'CriticalText'
 local TextColumn = require 'TextColumn'
@@ -40,6 +38,9 @@ local PLOT_GRID_Y_N = 4
 
 local ARC_WIDTH = 2
 
+local DIAL_THETA0 = 90
+local DIAL_THETA1 = 360
+
 --------------------------------------------------------------------------------
 -- helper functions
 
@@ -283,7 +284,7 @@ end
 
 M.dial = function(x, y, radius, thickness, threshold)
    return _G_Widget_.Dial(
-      _G_Widget_.make_semicircle(x, y, radius, 90, 360),
+      _G_Widget_.make_semicircle(x, y, radius, DIAL_THETA0, DIAL_THETA1),
       _G_Widget_.arc_style(thickness, _G_Patterns_.INDICATOR_BG),
       _G_Widget_.threshold_style(
          _G_Patterns_.INDICATOR_FG_PRIMARY,
@@ -293,6 +294,24 @@ M.dial = function(x, y, radius, thickness, threshold)
    )
 end
 
+--------------------------------------------------------------------------------
+-- compound dial
+
+M.compound_dial = function(x, y, outer_radius, inner_radius, thickness,
+                           threshold, num_dials)
+   return _G_Widget_.CompoundDial(
+      _G_Widget_.make_semicircle(x, y, outer_radius, DIAL_THETA0, DIAL_THETA1),
+      _G_Widget_.arc_style(thickness, _G_Patterns_.INDICATOR_BG),
+      _G_Widget_.threshold_style(
+         _G_Patterns_.INDICATOR_FG_PRIMARY,
+         _G_Patterns_.INDICATOR_FG_CRITICAL,
+         threshold
+      ),
+      inner_radius,
+      num_dials
+   )
+end
+
 --------------------------------------------------------------------------------
 -- separator (eg a horizontal line)
 
diff --git a/drawing/Processor.lua b/drawing/Processor.lua
index cd12737..f3a4e43 100644
--- a/drawing/Processor.lua
+++ b/drawing/Processor.lua
@@ -56,19 +56,14 @@ local _create_core_ = function(cores, id, x, y)
    end
 
    cores[id +1] = {
-	  dials = _G_Widget_.CompoundDial(
-         _G_Widget_.make_semicircle(x, y, _DIAL_OUTER_RADIUS_, 90, 360),
-         _G_Widget_.arc_style(
-            _DIAL_THICKNESS_,
-            _G_Patterns_.INDICATOR_BG
-         ),
-         _G_Widget_.threshold_style(
-            _G_Patterns_.INDICATOR_FG_PRIMARY,
-            _G_Patterns_.INDICATOR_FG_CRITICAL,
-            0.8
-         ),
-		 _DIAL_INNER_RADIUS_,
-		 NUM_THREADS_PER_CORE
+	  dials = Common.compound_dial(
+         x,
+         y,
+         _DIAL_OUTER_RADIUS_,
+         _DIAL_INNER_RADIUS_,
+         _DIAL_THICKNESS_,
+         0.8,
+         NUM_THREADS_PER_CORE
 	  ),
       text_ring = Common.initTextRing(
          x,