diff --git a/script/device/Pixel.py b/script/device/Pixel.py
index 21a0746..dfcd170 100644
--- a/script/device/Pixel.py
+++ b/script/device/Pixel.py
@@ -54,10 +54,12 @@ class Pixel(DeviceBase, Readable):
         self._update_header_length();
 
     def get_count_id(self):
-          return caget (self.prefix + ":FNUM", 'i') 
+          ret = caget (self.prefix + ":FNUM", 'i') 
+          setCache(ret, None)
 
     def set_count_id(self, val):
           caput (self.prefix + ":FNUM", int(val)) 
+          setCache(ret, int(val))
 
     def get_expose(self):
           return caget (self.prefix + ":EXPOSE", 'd') / 1000.0
@@ -176,6 +178,7 @@ class Pixel(DeviceBase, Readable):
                     
     def doUpdate(self):
         self.get_status()
+        self.get_count_id()
         
     def read(self):
         return None