Changeset 140

Timestamp:

12/16/09 08:30:44 (15 years ago)

Author:

ogrimm

Message:

Removed automatic gain control in feedback

Location:

drsdaq

Files:

• HVFeedback.cc (modified) (4 diffs)
• History.txt (modified) (1 diff)

drsdaq/HVFeedback.cc

@@ -64 +64 @@
     ReadCard("DefaultResponse",      Response,           'f', File, m->NumBoards*kNumberOfChips*kNumberOfChannels);
     ReadCard("DefaultTarget",        Target,             'f', File, m->NumBoards*kNumberOfChips*kNumberOfChannels);
+    // Add also initial gain to configuration parameters
     fclose(File);
   }
@@ -69 +70 @@
  
   // Initial state
-  Gain = 1;
+  Gain = 0.2;
   SetFBMode(FB_Off);
   SetNumAverages(fDefaultNumAverage);
@@ -112 +113 @@
 bool HVFeedback::ProcessEvent() {
   int i,j,k,q;
-  float Correction, Integral, Difference, EffectiveGain;
+  float Correction, Integral, Difference;
   
   // Check for LED trigger channel on given channel and if feedback running
@@ -153 +154 @@
           case FB_Active:   // Determine correction from response maxtrix and change voltages
             Difference = Target[i][j][k] - Average[i][j][k];
-            EffectiveGain = Gain*pow(0.5*(1+(Difference/Sigma[i][j][k]-1)/(Difference/Sigma[i][j][k]+1)),2);
-            Correction = -Difference*Response[i][j][k]*EffectiveGain;
-            if (fabs(Correction) > 0.1) Correction = fabs(Correction)/Correction*0.1;   // Limit changes to 100 mV
+            Correction = -Difference*Response[i][j][k]*Gain;
+            //if (fabs(Correction) > 0.1) Correction = fabs(Correction)/Correction*0.1;   // Limit changes to 100 mV
             if(Correction!=0 && Target[i][j][k]!=0 && !PixMap->DRS_to_Pixel(i,j,k).empty()) {
               printf("Average of board %d, chip %d, channel %d is %.2f +/- %.2f    Correction %.3f\n",i,j,k,Average[i][j][k],Sigma[i][j][k],Correction);

drsdaq/History.txt

@@ -56 +56 @@
 23/9/2009   Fixed bug in RawDataCTX.cc: sequential event number in a file is only
             the same as the event number in the run for the first file part
+16/12/2009  Removed automatic gain adaption in feedback (caused spikes in the correction)