diff -u -r1.2 -r1.3
--- HPSSVTData.java	28 Mar 2012 00:07:08 -0000	1.2
+++ HPSSVTData.java	29 Mar 2012 03:55:50 -0000	1.3
@@ -1,102 +1,204 @@

 
 package org.lcsim.hps.recon.tracking;
 

-//--- org.lcsim ---//
-import org.lcsim.detector.tracker.silicon.SiSensor;
-

 /**

- *
- * @author Omar Moreno
- * @version $Id: HPSSVTData.java,v 1.2 2012/03/28 00:07:08 jeremy Exp $

+ * 
+ * 
+ * @author Omar Moreno <[log in to unmask]>
+ * @version $Id: HPSSVTData.java,v 1.3 2012/03/29 03:55:50 omoreno Exp $

  */
 public class HPSSVTData {
     

+    // Masks used to encode SVT hit information
+    public static final int HYBRID_MASK = 0x3;
+    public static final int APV_MASK = 0x7;
+    public static final int CHANNEL_MASK = 0x7F;
+    public static final int FPGA_MASK = 0xFFFF;
+    public static final int SAMPLE_MASK = 0x3FFF;

-    int[] data = new int[4];
-    SiSensor sensor;
-    Integer channelNumber;
-    short[] adc;
-    int apvNumber;
-    int hybridNumber;
-    int fpgaNumber;

+    // 4x32 
+    int[] sample = new int[4];

-    public HPSSVTData(SiSensor sensor, Integer channelNumber, short[] adc)

+    /**
+     * 
+     * Creates an SVT data packet from
+     * 
+     * @param hybridNumber 
+     *      Hybrid number (0-3)
+     * @param apvNumber
+     *      APV25 chip number (0-4)
+     * @param channelNumber
+     *      Sensor strip number (0-127)
+     * @param fpgaAddress
+     *      FPGA address
+     * @param adc 
+     *      ADC samples obtained by sampling the shaper output. Currently, 
+     *      six samples are obtained per raw hit.
+     */
+    public HPSSVTData(int hybridNumber, int apvNumber, 
+                      int channelNumber, int fpgaAddress, short[] adc)

     {

-        this.sensor = sensor;
-        this.adc = adc;
-        this.channelNumber = channelNumber;

+        this.createSVTDataPacket(hybridNumber, apvNumber, 
+                                 channelNumber, fpgaAddress, adc);
+    }
+    
+    /**
+     * Creates and SVT data packet from existing SVT data
+     * 
+     * @param data
+     *      The packed data as int array of size 4
+     */
+    public HPSSVTData(int[] data)
+    {
+        if(sample.length != 4) 
+            throw new RuntimeException("Data sample size is not valid!");

-        createSVTData();

+        this.sample = data;

     }
     
     /**

-     * Get the packed data for this sample.
-     * @return The packed data as an int array of size 4.

+     * Get the packed data for this sample
+     * @return sample 
+     *      The packed data as an int array of size 4.

      */
     public int[] getData() {

-    	return data;

+    	return sample;

     }
     

-    private void createSVTData()

+    
+    /**
+     * Creates and SVT data packet
+     */
+    private void createSVTDataPacket(int hybridNumber, int apvNumber, 
+                                     int channelNumber, int fpgaAddress, short[] adc)

     {
         /*
          * Sample Data consists of the following: Z[xx:xx] = Zeros, O[xx:xx] = Ones

-         * data[0] = O[0], Z[0], Hybrid[1:0], Z[0], ApvChip[2:0], Z[0], Channel[6:0], FpgaAddress[15:0]
-         * data[1] = Z[1:0], Sample1[13:0]], Z[1:0], Sample0[13:0]
-         * data[2] = Z[1:0], Sample3[13:0]], Z[1:0], Sample2[13:0]
-         * data[3] = Z[1:0], Sample5[13:0]], Z[1:0], Sample4[13:0]

+         * sample[0] = O[0], Z[0], Hybrid[1:0], Z[0], ApvChip[2:0], Z[0], Channel[6:0], FpgaAddress[15:0]
+         * sample[1] = Z[1:0], Sample1[13:0]], Z[1:0], Sample0[13:0]
+         * sample[2] = Z[1:0], Sample3[13:0]], Z[1:0], Sample2[13:0]
+         * sample[3] = Z[1:0], Sample5[13:0]], Z[1:0], Sample4[13:0]

          * 

-         * <--Still need to add header and temperature information-->

          */ 
     

-        //--- data[0] ---//
-        //---------------//

+        //--- sample[0] ---//
+        //-----------------//

-        // Add the FPGA address
-        data[0] = ( ~(0xFFFF << 16) & data[0] ) | ( ( fpgaNumber & 0xFFFF ) << 16);

+        // The most significant digit of sample[0] is set to 1
+        sample[0] |= 0x80000000;

-        // Add the channel number
-        data[0] = ( ~(0x7F << 22) & data[0] ) | ( ( channelNumber%128 & 0x7F ) << 22);

+        // Insert the hybrid number
+        sample[0] = (sample[0] &= ~(HYBRID_MASK << 28)) | ((hybridNumber & HYBRID_MASK) << 28); 

-        // Add the chip number
-        apvNumber = (int) Math.floor(channelNumber/128);
-        data[0] = ( ~(0x7 << 26) & data[0] ) | ( ( apvNumber & 0x7 ) << 26);

+        // Insert the APV number
+        sample[0] = (sample[0] &= ~(APV_MASK << 24)) | ((apvNumber & APV_MASK) << 24); 

-        // Add the hybrid number
-        data[0] = ( ~(0x3 << 29) & data[0] ) | ( ( apvNumber & 0x3 ) << 29);

+        // Insert the channel number
+        sample[0] = (sample[0] &= ~(CHANNEL_MASK << 16)) | ((channelNumber & CHANNEL_MASK) << 16); 

-        //--- data[1] ----//
-        //----------------//

+        // Insert the FPGA address
+        sample[0] = (sample[0] &= ~FPGA_MASK) | (fpgaAddress & FPGA_MASK);
+        
+        
+        //--- sample[1] ----//
+        //------------------//

         
         // Add sample 0

-        data[1] = ( ~(0x3FFF << 14) & data[1] ) | ( ( adc[0] & 0x3FFF ) << 14);

+        sample[1] = (sample[1] &= ~SAMPLE_MASK) | (adc[0] & SAMPLE_MASK);

         
         // Add sample 1

-        data[1] = ( ~(0x3FFF << 29) & data[1] ) | ( ( adc[1] & 0x3FFF ) << 29);

+        sample[1] = (sample[1] &= ~(SAMPLE_MASK << 16)) | ((adc[1] & SAMPLE_MASK) << 16);
+

-        //--- data[2] ----//
-        //----------------//

+        //--- sample[2] ----//
+        //------------------//

         
         // Add sample 2

-        data[2] = ( ~(0x3FFF << 14) & data[2] ) | ( ( adc[2] & 0x3FFF ) << 14);

+        sample[2] = (sample[2] &= ~SAMPLE_MASK) | (adc[2] & SAMPLE_MASK);
+

         
         // Add sample 3

-        data[2] = ( ~(0x3FFF << 29) & data[2] ) | ( ( adc[3] & 0x3FFF ) << 29);

+        sample[2] = (sample[2] &= ~(SAMPLE_MASK << 16)) | ((adc[3] & SAMPLE_MASK) << 16);
+

-        //--- data[3] ----//
-        //----------------//

+        //--- sample[3] ----//
+        //------------------//

         
         // Add sample 4

-        data[3] = ( ~(0x3FFF << 14) & data[3] ) | ( ( adc[4] & 0x3FFF ) << 14);

+        sample[3] = (sample[3] &= ~SAMPLE_MASK) | (adc[4] & SAMPLE_MASK);
+

         
         // Add sample 5

-        data[3] = ( ~(0x3FFF << 29) & data[3] ) | ( ( adc[5] & 0x3FFF ) << 29);
-        
-        

+        sample[3] = (sample[3] &= ~(SAMPLE_MASK << 16)) | ((adc[5] & SAMPLE_MASK) << 16);
+

     }
     

+    /**
+     * Get the hybrid number associated with this SVT data packet
+     * @return hybrid number (0-3)
+     */
+    public int getHybridNumber()
+    {
+        return (sample[0] >>> 28) & HYBRID_MASK;
+    }

+    /**
+     * Get the APV number associated with this SVT data packet
+     * @return APV number (0-4)
+     */
+    public int getAPVNumber()
+    {
+        return (sample[0] >>> 24) & APV_MASK;
+    }
+    
+    /**
+     * Get the channel number associated with this SVT data packet
+     * @return channel number (0-127)
+     */
+    public int getChannelNumber()
+    {
+        return (sample[0] >>> 16) & CHANNEL_MASK;
+    }

+    /**
+     * Get the FPGA address associated with this SVT data packet  
+     * @return FPGA address
+     */
+    public int getFPGAAddress(int data)
+    {
+        return sample[0] & FPGA_MASK;
+    }
+    
+    /**
+     * Get the nth SVT sample
+     * @param n
+     *      The sample number of interest. Valid values are 0 to 5
+     * @throws RuntimeException if the sample number is out of range
+     * @return ADC value of the nth sample
+     * 
+     * 
+     */
+    public int getSample(int n)
+    {
+        
+        switch(n) {
+            case 0: 
+                return sample[1] & SAMPLE_MASK;
+            case 1:
+                return (sample[1] >>> 16) & SAMPLE_MASK;
+            case 2:
+                return sample[2] & SAMPLE_MASK;
+            case 3:
+                return (sample[2] >>> 16) & SAMPLE_MASK;
+            case 4: 
+                return sample[3] & SAMPLE_MASK;
+            case 5:
+                return (sample[3] >>> 16) & SAMPLE_MASK;
+            default:
+                throw new RuntimeException("Invalid sample number! Valid range of values for n are from 0 - 5");
+        }
+           
+    }

 }