diff --git a/src/main/java/Scienta.java b/src/main/java/Scienta.java
index 904e00c..075fc77 100644
--- a/src/main/java/Scienta.java
+++ b/src/main/java/Scienta.java
@@ -6,12 +6,14 @@ import ch.psi.pshell.device.CameraImageDescriptor;
 import ch.psi.pshell.device.MatrixCalibration;
 import ch.psi.pshell.device.Device;
 import ch.psi.pshell.device.DeviceAdapter;
+import ch.psi.pshell.device.DeviceListener;
 import ch.psi.pshell.device.Readable.ReadableCalibratedArray;
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.logging.Level;
 import ch.psi.pshell.epics.*;
+import ch.psi.utils.State;
 import java.util.concurrent.ExecutionException;
 import java.util.logging.Logger;
 
@@ -123,6 +125,39 @@ public class Scienta extends AreaDetector {
         stats[3] = new Stats("CountsR4", 4);
         stats[4] = new Stats("Counts", 5);
         addChildren(stats);
+        
+        stepTime.addListener(new DeviceAdapter() {
+            @Override
+            public void onValueChanged(Device device, Object value, Object former) {
+                int time_ms = (int) (((Double) value) * 1000);
+                Integer num_frames = time_ms / 40;
+                if (num_frames != frames.take()){
+                    frames.writeAsync(num_frames);
+                }
+            }
+
+            @Override
+            public void onValueChanging(Device device, Object value, Object former) throws Exception {
+                //Value must be multiple of 40ms
+                int val_ms = (int) (((Double) value) * 1000);
+                if ((val_ms % 40) != 0){
+                    throw new IOException("Value must be multiple of 40ms");
+                }                                
+            }
+        });
+        
+        frames.addListener(new DeviceAdapter() {
+            @Override
+            public void onValueChanged(Device device, Object value, Object former) {
+                int num_frames = (Integer)value;
+                int time_ms = num_frames * 40;
+                Double time = ((double)time_ms) / 1000.0;
+                if (time != stepTime.take()){
+                    stepTime.writeAsync(time);
+                }
+                
+            }
+        });        
     }
 
     public class ScientaSpectrum extends ChannelDoubleArray implements ReadableCalibratedArray<double[]> {
diff --git a/src/main/java/ScientaPanel.java b/src/main/java/ScientaPanel.java
index a5475d0..5ea8d6f 100644
--- a/src/main/java/ScientaPanel.java
+++ b/src/main/java/ScientaPanel.java
@@ -43,6 +43,10 @@ public final class ScientaPanel extends DevicePanel {
                     } else if (origin == valueHigh) {
                         getDevice().getHighEnergy().writeAsync(value);
                     } else if (origin == valueTime) {
+                        int val_ms = (int) (((Double) value) * 1000);
+                        if ((val_ms % 40) != 0){
+                            throw new IOException("Value must be multiple of 40ms");
+                        }                                
                         getDevice().getStepTime().writeAsync(value);
                     } else if (origin == valueSize) {
                         getDevice().getStepSize().writeAsync(value);