diff --git a/site_ansto/instrument/hrpd/hrpd_configuration.tcl b/site_ansto/instrument/hrpd/hrpd_configuration.tcl
index d07d183e..5b57830b 100644
--- a/site_ansto/instrument/hrpd/hrpd_configuration.tcl
+++ b/site_ansto/instrument/hrpd/hrpd_configuration.tcl
@@ -1,5 +1,5 @@
-# $Revision: 1.1 $
-# $Date: 2006-05-08 22:31:50 $
+# $Revision: 1.2 $
+# $Date: 2006-05-09 05:08:50 $
 # Author: Ferdi Franceschini (ffr@ansto.gov.au)
 # Last revision by: $Author: ffr $
 
@@ -472,7 +472,7 @@ proc SplitReply { text } {
      set l [split $text =]
      return [lindex $l 1]
 }
-# virtual motor d1(h)orizontal (width)
+# virtual motor ss1(h)orizontal (width)
 #--------------------------------------------------------
 proc widthscript {val} {
 	set currentWidth [expr [SplitReply [ss1r]] + [SplitReply [ss1l]]]
@@ -487,11 +487,35 @@ proc readwidth {} {
 	return [expr [SplitReply [ss1r]] + [SplitReply [ss1l]]] 
 }
 publish readwidth user
-#-------------------------------------------------------
 MakeConfigurableMotor ss1hg
 ss1hg drivescript widthscript
 ss1hg readscript readwidth
-# virtual motor d1v(ertical), height
+
+# virtual motor ss1(h)orizontal (offset)
+#--------------------------------------------------------
+proc horoffsetscript {val} {
+  set SR [SplitReply [ss1r]]
+  set SL [SplitReply [ss1l]]
+	set currentOffset [ expr $SR - ($SR + $SL)/2.0 ] 
+	set diff [expr $val - $currentOffset]
+	set newD1R [expr $SR + $diff]
+	set newD1L [expr $SL - $diff]
+	return "ss1r=$newD1R,ss1l=$newD1L"
+}
+publish horoffsetscript user
+#-------------------------------------------------------
+proc readhoroffset {} {
+  set SR [SplitReply [ss1r]]
+	return [ expr $SR - ($SR + [SplitReply [ss1l]])/2.0 ] 
+}
+publish readhoroffset user
+
+#-------------------------------------------------------
+MakeConfigurableMotor ss1ho
+ss1ho drivescript horoffsetscript
+ss1ho readscript readhoroffset
+
+# virtual motor ss1v(ertical), height
 #-----------------------------------------------------
 proc heightscript {val} {
 	set currentWidth [expr [SplitReply [ss1u]] + [SplitReply [ss1d]]]
@@ -511,3 +535,26 @@ MakeConfigurableMotor ss1vg
 ss1vg drivescript heightscript
 ss1vg readscript readheight
 
+# virtual motor ss1(v)ertical (offset)
+#--------------------------------------------------------
+proc vertoffsetscript {val} {
+  set SU [SplitReply [ss1u]]
+  set SD [SplitReply [ss1d]]
+	set currentOffset [ expr $SU - ($SU + $SD)/2.0 ] 
+	set diff [expr $val - $currentOffset]
+	set newD1U [expr $SU + $diff]
+	set newD1D [expr $SD - $diff]
+	return "ss1u=$newD1U,ss1d=$newD1D"
+}
+publish vertoffsetscript user
+#-------------------------------------------------------
+proc readvertoffset {} {
+  set SU [SplitReply [ss1u]]
+	return [ expr $SU - ($SU + [SplitReply [ss1d]])/2.0 ] 
+}
+publish readvertoffset user
+
+#-------------------------------------------------------
+MakeConfigurableMotor ss1vo
+ss1vo drivescript vertoffsetscript
+ss1vo readscript readvertoffset