ITS/AliITSRawStreamSDD.cxx

   1 /**************************************************************************
   2  * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
   3  *                                                                        *
   4  * Author: The ALICE Off-line Project.                                    *
   5  * Contributors are mentioned in the code where appropriate.              *
   6  *                                                                        *
   7  * Permission to use, copy, modify and distribute this software and its   *
   8  * documentation strictly for non-commercial purposes is hereby granted   *
   9  * without fee, provided that the above copyright notice appears in all   *
  10  * copies and that both the copyright notice and this permission notice   *
  11  * appear in the supporting documentation. The authors make no claims     *
  12  * about the suitability of this software for any purpose. It is          *
  13  * provided "as is" without express or implied warranty.                  *
  14  **************************************************************************/
  15
  16 /* $Id$ */
  17
  18 ///////////////////////////////////////////////////////////////////////////////
  19 ///
  20 /// This class provides access to ITS SDD digits in raw data.
  21 ///
  22 ///////////////////////////////////////////////////////////////////////////////
  23
  24 #include "AliITSRawStreamSDD.h"
  25 #include "AliRawReader.h"
  26
  27 ClassImp(AliITSRawStreamSDD)
  28
  29 const Int_t AliITSRawStreamSDD::fgkDDLModuleMap[kDDLsNumber][kModulesPerDDL] = {
  30   {240,241,242,246,247,248,252,253,254,258,259,260,264,265,266,270,271,272,276,277,278,-1},
  31   {243,244,245,249,250,251,255,256,257,261,262,263,267,268,269,273,274,275,279,280,281,-1},
  32   {282,283,284,288,289,290,294,295,296,300,301,302,306,307,308,312,313,314,318,319,320,-1},
  33   {285,286,287,291,292,293,297,298,299,303,304,305,309,310,311,315,316,317,321,322,323,-1},
  34   {324,325,326,327,332,333,334,335,340,341,342,343,348,349,350,351,356,357,358,359,364,365},
  35   {328,329,330,331,336,337,338,339,344,345,346,347,352,353,354,355,360,361,362,363,368,369},
  36   {366,367,372,373,374,375,380,381,382,383,388,389,390,391,396,397,398,399,404,405,406,407},
  37   {370,371,376,377,378,379,384,385,386,387,392,393,394,395,400,401,402,403,408,409,410,411},
  38   {412,413,414,415,420,421,422,423,428,429,430,431,436,437,438,439,444,445,446,447,452,453},
  39   {416,417,418,419,424,425,426,427,432,433,434,435,440,441,442,443,448,449,450,451,456,457},
  40   {454,455,460,461,462,463,468,469,470,471,476,477,478,479,484,485,486,487,492,493,494,495},
  41   {458,459,464,465,466,467,472,473,474,475,480,481,482,483,488,489,490,491,496,497,498,499}};
  42
  43 const UInt_t AliITSRawStreamSDD::fgkCodeLength[8] =  {8, 18, 2, 3, 4, 5, 6, 7};
  44
  45 AliITSRawStreamSDD::AliITSRawStreamSDD(AliRawReader* rawReader) :
  46   AliITSRawStream(rawReader)
  47 {
  48 // create an object to read ITS SDD raw digits
  49
  50   fData = 0;
  51   fSkip = 0;
  52   fEventId = 0;
  53   fCarlosId = 0;
  54   fChannel = 0;
  55   fJitter  = 0;
  56   for(Int_t i=0;i<2;i++){
  57     fChannelData[i]=0;
  58     fLastBit[i]=0;
  59     fChannelCode[i]=0;
  60     fReadCode[i]=kFALSE;
  61     fReadBits[i]=0;
  62     fTimeBin[i]=0;
  63     fAnode[i]=0;
  64     fLowThreshold[i]=0;
  65   }
  66   fRawReader->Select("ITSSDD");
  67
  68 }
  69
  70 UInt_t AliITSRawStreamSDD::ReadBits()
  71 {
  72 // read bits from the given channel
  73
  74   UInt_t result = (fChannelData[fChannel] & ((1<<fReadBits[fChannel]) - 1));
  75   fChannelData[fChannel] >>= fReadBits[fChannel];
  76   fLastBit[fChannel] -= fReadBits[fChannel];
  77   return result;
  78 }
  79
  80 Int_t AliITSRawStreamSDD::DecompAmbra(Int_t value) const
  81 {
  82 // AMBRA decompression
  83
  84   if ((value & 0x80) == 0) {
  85     return value & 0x7f;
  86   } else if ((value & 0x40) == 0) {
  87     return 0x081 + ((value & 0x3f) << 1);
  88   } else if ((value & 0x20) == 0) {
  89     return 0x104 + ((value & 0x1f) << 3);
  90   } else {
  91     return 0x208 + ((value & 0x1f) << 4);
  92   }
  93 }
  94
  95 Bool_t AliITSRawStreamSDD::Next()
  96 {
  97 // read the next raw digit
  98 // returns kFALSE if there is no digit left
  99
 100   fPrevModuleID = fModuleID;
 101   if (!fRawReader->ReadNextInt(fData)) return kFALSE;
 102
 103   UInt_t relModuleID = (fData >> 25) & 0x0000007F;
 104   fModuleID = fgkDDLModuleMap[fRawReader->GetDDLID()][relModuleID];
 105   fCoord1 = (fData >> 16) & 0x000001FF;
 106   fCoord2 = (fData >> 8) & 0x000000FF;
 107   fSignal = fData & 0x000000FF;
 108
 109   return kTRUE;
 110 }
 111