diff --git a/src/HallC_LinkDef.h b/src/HallC_LinkDef.h
index e0ceea5f38f10322fbb8163b9079858f0e0c4b9d..7a5e99db8d6d02eb19039c5cacb0f73c088530e3 100644
--- a/src/HallC_LinkDef.h
+++ b/src/HallC_LinkDef.h
@@ -5,6 +5,7 @@
 #pragma link off all functions;
 
 #pragma link C++ global gHcParms;
+#pragma link C++ global gHcDetectorMap;
 
 #pragma link C++ class THcInterface+;
 #pragma link C++ class THcParmList+;
diff --git a/src/THcDetectorMap.cxx b/src/THcDetectorMap.cxx
index 710c5d282e9b072c65f0bbe7b9aac55f9ba1dabf..76141676e1013d2d67829d58333ee7282faccae4 100644
--- a/src/THcDetectorMap.cxx
+++ b/src/THcDetectorMap.cxx
@@ -32,11 +32,70 @@ inline static bool IsComment( const string& s, string::size_type pos )
 	   (s[pos] == '!') );
 }
 
-virtual Int_t THcDetectorMap::FillMap(THaDetMap *detmap, string *detectorname) {
-  Int_t detectorid=3;  // Get this from detectorname
-  
-  // Loop through the list looking for all hardware channels that
-  //  are detectorid.  Sort and try to minimize AddModule calls
+//_____________________________________________________________________________
+THcDetectorMap::THcDetectorMap() : fNchans(0)
+{
+}
+
+//_____________________________________________________________________________
+THcDetectorMap::~THcDetectorMap()
+{
+}
+
+//bool THcDetectorMap::compare(const ChaninMod *first, const ChaninMod *second) {
+//      return((first->channel < second->channel)? true: false);
+//}
+struct Functor
+{
+  bool operator() (const THcDetectorMap::ChaninMod &first, const THcDetectorMap::ChaninMod &second)
+  { return((first.channel < second.channel)? true: false);}
+};
+//_____________________________________________________________________________
+Int_t THcDetectorMap::FillMap(THaDetMap *detmap, const char *detectorname)
+// Should probably return a status
+{
+  list<ModChanList>::iterator imod;
+  ChaninMod Achan;
+  ModChanList Amod;
+
+  // Need one array of uniq crate/slot combos
+
+  // Translate detector name into and ID
+  Int_t did=3;  // Get this from detectorname
+  mlist.clear();
+
+  for(Int_t ich=0;ich<fNchans;ich++) {
+    if(fTable[ich].did == did) {
+      Int_t roc=fTable[ich].roc;
+      Int_t slot=fTable[ich].slot;
+      for(imod=mlist.begin(); imod!= mlist.end(); ++imod) {
+	Achan.channel = fTable[ich].channel;
+	Achan.plane = fTable[ich].plane;
+	Achan.counter = fTable[ich].counter;
+	Achan.signal = fTable[ich].signal;
+	if((*imod).roc == roc && (*imod).slot == slot) {
+	  (*imod).clist.push_back(Achan);
+	}
+      }
+      if(imod == mlist.end()) {
+	Amod.roc = roc;
+	Amod.slot = slot;
+	Amod.clist.clear();
+	Amod.clist.push_back(Achan);
+	mlist.push_back(Amod);
+      }
+    }
+  }
+  if(mlist.size() <= 0) {
+    return(-1);
+  }
+  Functor f;
+  for(imod=mlist.begin(); imod!= mlist.end(); ++imod) {
+    list<ChaninMod> *clistp = &((*imod).clist);
+    clistp->sort(f);//Sort by channel
+  }
+    
+  return(0);
 }
 
 void THcDetectorMap::Load(const char *fname)
@@ -60,6 +119,8 @@ void THcDetectorMap::Load(const char *fname)
   Int_t detector=0;
   Int_t slot=0;
 
+  fNchans = 0;
+
   string::size_type start, pos=0;
 
   char varname[100];
@@ -126,7 +187,16 @@ void THcDetectorMap::Load(const char *fname)
 	signal= ((TObjString*)vararr->At(3))->GetString().Atoi();
       }
       cout << channel << " " << plane << " " << counter << " " << signal << endl;
-      
+
+      fTable[fNchans].roc=roc;
+      fTable[fNchans].roc=slot;
+      fTable[fNchans].channel=channel;
+      fTable[fNchans].did=detector;
+      fTable[fNchans].plane=plane;
+      fTable[fNchans].counter=counter;
+      fTable[fNchans].signal=signal;
+
+      fNchans++;
     }
   }
 
diff --git a/src/THcDetectorMap.h b/src/THcDetectorMap.h
index 9d1b8c2d70913b52cea0fb884505604504f45329..02c59c650a3b8134bd7ef58a4554404b5bad3345 100644
--- a/src/THcDetectorMap.h
+++ b/src/THcDetectorMap.h
@@ -8,23 +8,46 @@
 //////////////////////////////////////////////////////////////////////////
 
 #include "TObject.h"
+#include "THaDetMap.h"
+#include <list>
 
 class THcDetectorMap : public TObject {
 
  public:
-  THcDetectorMap() {}
-  virtual ~THcDetectorMap() {}
+  THcDetectorMap();
+  virtual ~THcDetectorMap();
   
   virtual void Load(const char *fname);
-
-  // Member variables needed
-  // List of detector IDs.
-  // Hardware to logical detector mapping for each detector
-  // Mapping between detector names and numbers
-  // Hardwire, but later configure
-  struct Detector {
-    UInt_t did; 	// Numberical Detector ID
-    TList* 
+  virtual Int_t FillMap(THaDetMap* detmap, const char* detectorname);
+
+  Int_t fNchans;  // Number of hardware channels
+
+  struct Channel { // Mapping for one hardware channel
+    Int_t roc;
+    Int_t slot;
+    Int_t channel;
+    Int_t did;
+    Int_t plane;
+    Int_t counter;
+    Int_t signal;
+  };
+  Channel fTable[10000]; // Big ugly cache of the map file
+
+  struct ChaninMod {
+    Int_t channel;
+    Int_t plane;
+    Int_t counter;
+    Int_t signal;
+  };
+  struct ModChanList {
+    Int_t roc;
+    Int_t slot;
+    std::list<ChaninMod> clist;
+      
+  };
+  std::list<ModChanList> mlist;
+
+  bool compare(const ChaninMod *first, const ChaninMod *second);
 
  protected:
 
diff --git a/src/THcHodoscope.cxx b/src/THcHodoscope.cxx
index 074c90010537dbf26c0bc25504bae7f548c70671..221dab60bccb6f0a166106a30d8732f44a1cffab 100644
--- a/src/THcHodoscope.cxx
+++ b/src/THcHodoscope.cxx
@@ -53,6 +53,7 @@ THcHodoscope::THcHodoscope( ) :
 //_____________________________________________________________________________
 THaAnalysisObject::EStatus THcHodoscope::Init( const TDatime& date )
 {
+  static const char* const here = "Init()";
   // Extra initialization for scintillators: set up DataDest map
 
   if( THaNonTrackingDetector::Init( date ) )