Daphne Tape Format                                                  Page 1
        Overview                                                    10 August 1992


          1  Overview

          A Daphne data tape consists of a series of  files  separated  by  file
          marks.   The  last  file  is  followed  by  two file marks.  Each file
          consists of several header blocks and one or more data blocks.   There
          is nothing special written preceding the first run on the tape:  there
          is no volume label.

          When a run is started with the $ACQ command the tape processs does NOT
          immediately  write  out  the  header  information.   The  tape process
          postpones writing header information until the first block of data  is
          received.   For  a  run  in which no data is generated nothing will be
          written to tape.

          Each $ACQ command for which there is data begins a new file.  The $STP
          command,  if  any  data  is  written  to tape, ends the file, writes a
          double end-of-file, and backspaces the tape  so  as  to  position  the
          write  head  before  the  last end-of-file mark in preparation for the
          next run.

          VAX/VMS uses the ascii character code.  Fields in Daphne records which
          are described as text or character will be in ascii.  Lower case ascii
          is also used in some places.   The  IBM/370  series  uses  the  EBCDIC
          character code rather than ascii.

          On the VAX the low order byte of  a  word  is  placed  at  the  lowest
          address  of  the  word.   This  is in contrast to such machines as the
          IBM/370 series which place the high order byte at the  lowest  address
          of the word.

          The VAX like  the  IBM/370  series  represents  integers  using  two's
          complement format.

          Each block, regardless of type, begins with a two character code,  the
          first of which is usually alphabetic.

          The largest tape blocks generated by Daphne at this time are  slightly
          less  than  13  kbytes  long.   There will always be an even number of
          bytes in a tape block.

                                           NOTE

                  It is unlikely that Daphne will ever use  block  sizes
                  larger than 20 kbytes

          The user can force Daphne to use a smaller block size  for  data  with
          the "/RECORD" qualifier of the $TAPE/OUT command.
        Daphne Tape Format                                                  Page 2
        Example Programs                                            10 August 1992


          2  Example Programs

          The Daphne developers have written  a  simple  Fortran  program  which
          demonstrates  how  to read a Daphne data tape.  It is a self-contained
          program written in Fortran-77 with symbols limited  to  6  characters.
          The  user must provide system dependent Fortran subroutines to perform
          tape operations and an analysis routine which is called once for  each
          event.  The program consists of the following files:

                        DAP$DISK:[DAPHNE.EXPORT]DAPTAP.FOR
                        DAP$DISK:[DAPHNE.EXPORT]TAPCOM.INC
                        DAP$DISK:[DAPHNE.EXPORT]LUNCOM.INC

          This version of the program will run without changes under VAX/VMS.  I
          want  to  emphasize  that  some  of the routines are system dependent,
          however, I have tried to encapsulate each system dependent feature  in
          a well documented subroutine.

          B.  Crowell of Yale University has used code from the above program to
          convert  Daphne  event  format  tapes  to Oak Ridge format tapes.  The
          source code is in the directory DAP$DISK:[DAPHNE.EXPORT.DAPOAK] He has
          also  written  a  program  to  convert many histogram formats to other
          histogram  formats.    The   source   code   is   in   the   directory
          DAP$DISK:[DAPHNE.EXPORT.TRAN].
        Daphne Tape Format                                                  Page 3
        Identifier Header Block                                     10 August 1992


          3  Identifier Header Block

          A run begins with a record of type "A0" which is  entirely  in  ascii.
          It  identifies  the  tape  ("Daphne Argonne National Laboratory")  and
          gives the maximum number of bytes in any block of the file,  12288  in
          the example below.

          Ignore the statement that the shortest record is  256  bytes.   It  is
          wrong.


                  Block number 1 (00000001), 256 (0100) bytes 
                  Read hexadecimal from right to left 

                  C        8        4        0 
           4E4E4F47 52412045 4E485041 44203041 A0 DAPHNE ARGONN 000000 
           524F4241 4C204C41 4E4F4954 414E2045 E NATIONAL LABOR 000010 
           49442053 43495359 48502059 524F5441 ATORY PHYSICS DI 000020 
           52204D55 4D495841 4D204E4F 49534956 VISION MAXIMUM R 000030 
           32323120 3D20455A 49532044 524F4345 ECORD SIZE = 122 000040 
           20202020 20202020 20202020 20203838 88               000050 
           45522054 53455452 4F485320 20202020      SHORTEST RE 000060 
           20202020 20363532 20203D20 44524F43 CORD =  256      000070 
           20202020 20202020 20202020 20202020                  000080 
           20202020 20202020 20202020 20202020                  000090 
           20202020 20202020 20202020 20202020                  0000A0 
           20202020 20202020 20202020 20202020                  0000B0 
           20202020 20202020 20202020 20202020                  0000C0 
           20202020 20202020 20202020 20202020                  0000D0 
           20202020 20202020 20202020 20202020                  0000E0 
           20202020 20202020 20202020 20202020                  0000F0 
        Daphne Tape Format                                                  Page 4
        DAQ Header Block                                            10 August 1992


          4  DAQ Header Block

          The second block of a run is the  DAQ  (Data  Acquisition  Parameters)
          control block with a buffer type code of "B0".  The DAQ is in a format
          that is designed to make it easy  to  add  new  parameters  or  remove
          obsolete  parameters.   DAQ  parameters  are either 32 bit integers or
          character strings.  DAQ parameters of type character have fixed length
          and  are  blank filled.  The longest character string at the moment is
          the "comment" field which is 60 characters long.

          Following the buffer type code is a two byte filler and then a 32  bit
          integer giving the dimension of a 2 by N array of descriptors.  In the
          example below there are 61 decimal (3D hexadecimal)  data  acquisition
          parameters.  The array begins at byte 8 of the block.

          Element (1,i) is a 4 character ascii code (in lowercase!) for the name
          of  parameter "i".  Element (2,i) is a 32 bit number giving the number
          of bytes required to store the value of parameter  "i".   A  table  of
          identifier codes is at the end of this document.

          After the last descriptor and a 4 byte gap begins the  DAQ  parameters
          themselves  in  the  same  order  as  they  appeared  in  the array of
          descriptors.  Since all integer DAQ parameters come first they will be
          aligned  to a multiple of 4 boundary.  Character DAQ parameters follow
          integer parameters and are packed without regard for word alignment.

        Daphne Tape Format                                                  Page 5
        DAQ Header Block                                            10 August 1992



                  Block number 2 (00000002), 1064 (0428) bytes 
                  Read hexadecimal from right to left 

                  C        8        4        0 
           00000004 76616161 0000003D 20203042 B0  =...aaav.... 000000 aaav at 1F4 
           -------^ -------^ -------^ ---^---^ 
            4 bytes  "aaav"   DAQ Count  |  ID 
            required                     | 
           for "aaav"                  Filler 
                                           
           00000004 616D6163 00000004 73667562 bufs....cama.... 000010 bufs at 1F8 
           00000004 646E6F63 00000004 65646F63 code....cond.... 000020 
           00000004 63707364 00000004 746E6F63 cont....dspc.... 000030 
           00000004 72636865 00000004 6C707364 dspl....ehcr.... 000040 
           00000004 6C736865 00000004 65726865 ehre....ehsl.... 000050 
           00000004 63786966 00000004 73737665 evss....fixc.... 000060 evss at 220 
           00000004 70747366 00000004 63746C66 fltc....fstp.... 000070 
           00000004 736D3168 00000004 69643168 h1di....h1ms.... 000080 
           00000004 736D3268 00000004 69643268 h2di....h2ms.... 000090 
           00000004 3268616D 00000004 3168616D mah1....mah2.... 0000A0 
           00000004 326D616D 00000004 316D616D mam1....mam2.... 0000B0 
           00000004 6D706373 00000004 6D6C6373 sclm....scpm.... 0000C0 
           00000004 3278616D 00000004 3178616D max1....max2.... 0000D0 
           00000004 7377736E 00000004 6662736E nsbf....nsws.... 0000E0 
           00000004 7274756F 00000004 6E656E6F onen....outr.... 0000F0 
           00000004 7270746F 00000004 6470746F otpd....otpr.... 000100 
           00000004 65666173 00000004 66626472 rdbf....safe.... 000110 
           00000004 646C6373 00000004 6C616373 scal....scld.... 000120 scld at 284 
           00000004 73706373 00000004 736C6373 scls....scps.... 000130 
           00000004 6D637074 00000004 61626174 taba....tpcm.... 000140 
           00000004 73777876 00000004 73736775 ugss....vxws.... 000150 
           00000004 62643277 00000004 73643177 w1ds....w2db.... 000160 
           00000004 73643277 00000004 63643277 w2dc....w2ds.... 000170 
           00000006 6D616562 000000C8 74736574 test....beam.... 000180 beam at 378 
           0000003C 6D6D6F63 00000004 636D6163 camc....comm<... 000190 comm at 382 
           00000006 72656E65 00000017 69747464 dtti....ener.... 0001A0 dtti at 3BE 
           00000008 746C756D 00000014 6E707865 expn....mult.... 0001B0 expn at 3D5 
           00000006 72646C6F 00000014 73796870 phys....oldr.... 0001C0 phys at 3DD 
           00000006 67726174 00000006 6E6E7572 runn....targ.... 0001D0 
           00000004 74726F76 00000006 73726576 vers....vort.... 0001E0 vers at 41D 
           00000002 00000018 00051586 00000000 ................ 0001F0 "gap" at 1F0
                                                                       aaav at 1F4
           0000000A 0000000E 00000050 00000064 d...P........... 000200 bufs at 1F8 
           00000014 00000000 00000001 00000064 d............... 000210 evss at 220 
           00000000 00000001 00000001 00000002 ................ 000220 
           00004D64 0000753C 0000465C 0000960C ....\F..<u..dM.. 000230 
           00000096 00000096 00000096 00000096 ................ 000240 
           00000014 00000032 0000000A 00000005 ........2....... 000250 
           00000010 00000001 00000000 00000018 ................ 000260 
           FFFFFFFF 0000001A 00003000 0000186A j....0.......... 000270 
           00000000 0000125C 00000005 00000005 ........\....... 000280 scld at 284 
           00000000 00000014 00000001 00000028 (............... 000290 
           00000000 00000003 00000014 00000000 ................ 0002A0 
           00000000 00000000 00000000 00000000 ................ 0002B0 
           00000000 00000000 00000000 00000000 ................ 0002C0 
           00000000 00000000 00000000 00000000 ................ 0002D0 
           00000000 00000000 00000000 00000000 ................ 0002E0 
        Daphne Tape Format                                                  Page 6
        DAQ Header Block                                            10 August 1992


           00000000 00000000 00000000 00000000 ................ 0002F0 
           00000000 00000000 00000000 00000000 ................ 000300 
           00000000 00000000 00000000 00000000 ................ 000310 
           00000000 00000000 00000000 00000000 ................ 000320 
           00000000 00000000 00000000 00000000 ................ 000330 
           00000000 00000000 00000000 00000000 ................ 000340 
           00000000 00000000 00000000 00000000 ................ 000350 
           00000019 00000000 00000001 00000000 ................ 000360 
           00002020 43323120 00000014 00000005 ........ 12C  .. 000370 beam at 378 
           52474544 20302054 41204353 4D200000 .. MSC AT 0 DEGR 000380 comm at 382 
           20202020 20202020 20202020 20534545 EES              000390 
           20202020 20202020 20202020 20202020                  0003A0 
           30332020 20202020 20202020 20202020               30 0003B0 dtti at 3BE 
           3A34343A 38302036 3839312D 4C554A2D -JUL-1986 08:44: 0003C0 
           52455354 2056454D 30323135 342E3831 18.45120MEV TSER 0003D0 expn at 3D5 
           00202020 20202020 20202020 41595552 RUYA           . 0003E0 
           41595552 52455354 20000000 00000000 ....... TSERRUYA 0003F0 
           00000000 00202020 20202020 20202020            ..... 000400 
           32353055 41373931 20202031 30302000 . 001   197AU052 000410 vers at 41D 
                             00202020 20363831 186    ......... 000420 

        Daphne Tape Format                                                  Page 7
        Event Structure Header Block                                10 August 1992


          5  Event Structure Header Block

          The event structure control block summarizes  the  $EVS  command.   As
          stored  on  tape it has a buffer type code of "B1" and is, by default,
          1024 bytes long.  The actual length can be determined  by  looking  at
          the  "evss"  field  of the DAQ block which gives the size of the event
          structure control block in units of 512 byte pages.

          What a user generally wants to know is  (a)  is  the  event  fixed  or
          variable length and (b) if fixed length how many words per event.


           -  Byte 6  EVS_VERSION (16 bit integer)

              The version number was changed to version 3 in February '86.

           -  Byte 8  EVS_SOE (16 bit integer)

              If zero this indicates that the events are variable length.  If it
              is  non-zero  then  events are of fixed length and its value gives
              the number of 16 bit words per event.


          The remaining bytes  will  not  generally  be  of  interest  to  users
          intending to process Daphne data tapes with their own programs.
        Daphne Tape Format                                                  Page 8
        Event Structure Header Block                                10 August 1992


          5.1  EVS for Variable Length Events



                  Block number 3 (00000003), 1024 (0400) bytes 
                  Read hexadecimal from right to left 

                  C        8        4        0 
           00100001 00000000 0003001A 04003142 B1.............. 000000 
                        ---^ ---^         ---^ 
                        SOE  Version       ID 

           00000000 00000001 00010000 00010005 ................ 000010 
           00000000 00000000 00000000 00000000 ................ 000020 

                  <Remainder all zeroes> 




          5.2  EVS for Fixed Length Events

          The example below is for a an experiment with fixed length events of 6
          words.

                  Block number 3 (00000003), 1024 (0400) bytes 
                  Read hexadecimal from right to left 

                  C        8        4        0 
           00100001 00000006 00030016 04003142 B1.............. 000000 
                        ---^ ---^         ---^ 
                        SOE  Version       ID 

           00000000 00000000 00000000 00000006 ................ 000010 
           00000000 00000000 00000000 00000000 ................ 000020 

                  <Remainder all zeroes> 
        Daphne Tape Format                                                  Page 9
        Event Data                                                  10 August 1992


          6  Event Data

          Each block of event data begins with a 20 byte  header  of  which  the
          first two bytes are a buffer type code of "D0".

          Blocks of event data can vary from 20 bytes to the maximum buffer size
          handled by Daphne, about 13 kbytes at the present time.  A short block
          is common at the end of a run when event data is flushed to tape.

          Events never span a block boundary.

          Following the last event in a tape block is a word with  all  16  bits
          set ('FFFF' hexadecimal).


           -  Byte 0  D0_ID (2 character ascii)

              Two character ascii buffer type code of "D0"

           -  Byte 2  D0_SIZE (16 bit integer)

              The number of bytes in this data block inclusive of the header and
              the event data.  This should match the number of bytes read by the
              tape drive.  The number of bytes in a  Daphne  data  block  should
              always be even.

           -  Byte 4  D0_HEAD_SIZE (16 bit integer)

              The number of bytes in the header.  For  the  current  version  of
              Daphne this will contain 20 (decimal).

           -  Byte 6  D0_VERSION (16 bit integer)

              The version number of the header format.  For the current  version
              of Daphne this will contain 1.

           -  Byte 8  D0_EP_ID (16 bit integer)

              The event processor that processed  this  buffer  of  event  data.
              This will contain a number between 1 and 16 (decimal).

           -  Byte 10 D0_BUF_TYPE (16 bit integer)

              This will always contain the value 5 for bt_tape.
        Daphne Tape Format                                                 Page 10
        Event Data                                                  10 August 1992


           -  Byte 12 D0_SEQ_NUMBER (32 bit integer)

              This is a sequence number generated by the  event  processors  for
              each  message  sent to the VAX.  Because of an oversight it cannot
              be used to check for lost or missing data buffers.  However it can
              be  used  with the event processor number to identify a particular
              block of a file.

           -  Byte 16 D0_CHECK_NUMBER (32 bit integer)

              This contains a 32 bit number chosen at random at the beginning of
              each  run.   It is intended to reduce to near zero the probability
              that an Event  Processor  that  wakes  up  after  acquisition  has
              started can transmit stale data to be recorded onto tape.


          There are two formats for storing event data  in  the  D0  data  block
          depending on whether events are of fixed length or variable length.



          6.1  Variable Length Event


          For variable length events each event is preceded by  a  control  word
          which  contains  the number of words in the event, the event type, and
          has the most significant bit set.  The count of  words  in  the  event
          includes  the control word itself, so a 4 word event would contain a 5
          in bits 13 through 4 of its control word.

                          Control Word Format 

                          FE   DCBD987654   3210  Bit Numbers 
                          XX   XXXXXXXXXX   XXXX 
                          -^   ---------^   ---^ 
                    sentinel   word count   Event type (0 to 15) 
             bit 15 always 1 
             bit 14 always 0 


                          Block number 5 (00000005), 12270 (2FEE) bytes 
                          Read hexadecimal from right to left 
                   
                          C        8        4        0 
                   000033CF 00050005 00010014 2FEE3044 D0./.........3.. 000000 
                   -------^ ---^---^ ---^---^ ---^---^ 
                   sequence tape   | version| size   | 
                     #       data  |        | (bytes)| 
                                   |   header        | 
                               event     size   buffer 
                           processor  (bytes)  type ID 
        Daphne Tape Format                                                 Page 11
        Event Data                                                  10 August 1992


                   
                   003E2000 00800000 00208080 09442AF1 .*D... ...... >. 000010 
                                         ---^ -------^ 
                        control word of first  check 
                              event in buffer  number 
                             8 words in event  
                   
                   03620080 00000020 000080C0 00000275 u....... .....b. 000020 
                                         ---^      
                       control word of second  
                              event in buffer 
                            12 words in event 
                   
                   00108080 05910000 00640219 038A039D ......d......... 000030 
                   3rd ---^ 
                   8 words 
                   
                   00108080 0289001B 002F1020 00100000 .... ./......... 000040 
                   00108080 037F0562 00301020 00040000 .... .0.b....... 000050 
                   00208080 0306060A 00331020 00020000 .... .3....... . 000060 
                   00108080 00000555 00332020 01000000 ....  3.U....... 000070 
                   00208080 02BA04EF 00361020 00040000 .... .6....... . 000080 
                   000080C0 00000619 00402020 01000000 ....  @......... 000090 
                   01D902AA 03CA0323 025D0080 00000020  .....].#....... 0000A0 
                   002A1020 00100000 00108080 05940000 ............ .*. 0000B0 
                   04380200 00000004 00028090 036E001C ..n...........8. 0000C0 
                   10200010 00000010 8080068F 03EC08DF .............. . 0000D0 
                   01000000 00010001 80D00263 06B70042 B...c........... 0000E0 
                   00000438 000000D1 03290372 042F0342 B./.r.).....8... 0000F0 
                   02BE0000 00271020 00010000 00108080 ........ .'..... 000100 
                   0266056A 00481020 00040000 00108080 ........ .H.j.f. 000110 
                   0271051D 00471020 00040000 00108080 ........ .G...q. 000120 
                   0320039F 03DC0080 00000020 000080C0 .... ......... . 000130 
                   
                          <Omitted data> 
                   
                   00040000 00108080 073904E0 00312020   1...9......... 002FA0 
                   00000001 000180D0 000005AA 003C1020  .<............. 002FB0 
                   04AC0000 04600396 02F3036A 03E90100 ....j.....`..... 002FC0 
                   02D4047E 01000000 00010001 80D00000 ............~... 002FD0 
                       FFFF 000004F3 00000809 02BC03C5 ................ 002FE0 
                       ---^ 
                       Word with all bits set 

                          <End of block> 

        Daphne Tape Format                                                 Page 12
        Event Data                                                  10 August 1992


          6.2  Fixed Length Events


          For fixed length events no control word is necessary since the  length
          is fixed and there can only be one event type.


                   Fixed Length Events of 6 Words 
                   
                          Block number 4 (00000004), 12274 (2FF2) bytes 
                          Read hexadecimal from right to left 
                   
                          C        8        4        0 
                   00000EE6 00050002 00010014 2FF23044 D0./............ 000000 
                   -------^ ---^---^ ---^---^ ---^---^ 
                   sequence tape   | version| size   | 
                     #       data  |        | (bytes)| 
                                   |   header        | 
                               event     size   buffer 
                           processor  (bytes)  type ID 
                   
                   0030028A 003401AA 00000022 CBEDE3BC ....".....4...0. 000010 
                                         ---^ -------^ 
                        first event in buffer    check 
                                                number 
                   
                   00000084 0030028C 00340354 00000022 "...T.4...0..... 000020 
                          second event in buffer  ---^ 
                   
                   003001AF 000000A0 003301AB 00340289 ..4...3.......0. 000030 
                   003201AA 00340209 00000024 00360479 y.6.$.....4...2. 000040 
                   00000082 00320351 0033028D 00000081 ......3.Q.2..... 000050 
                   002201DA 00000014 002C047C 003401B1 ..4.|.,.......". 000060 
                   002F01A9 0033028C 00000005 0034042B +.4.......3.../. 000070 
                   00000009 00300183 00340248 00000044 D...H.4...0..... 000080 
                   0033028D 00000012 0034023F 00300130 0.0.?.4.......3. 000090 
                   
                          <Remainder of block omitted> 

        Daphne Tape Format                                                 Page 13
        Scaler Data Block                                           10 August 1992


          7  Scaler Data Block

          Scaler information is in a block with buffer type code of "D1".

          When scalers are first defined space  is  allocated  for  the  maximum
          number  of scaler modules as given by the "sclm" parameter of the DAQ.
          In allocating space for the module space  is  also  allocated  for  32
          channels, the maximum number seen in any scaler module.

          At present the actual number of modules in use is not  stored  in  the
          header  however  one  can infer the number of modules because the word
          following the last defined scaler module will contain zero.

          The scaler control block contains a header and is  followed  by  space
          for  each  module  description  including a description of each of the
          channels of that module.

           -  Byte 0  SCLDIR_ID (two character ascii)

              ascii "D1".

           -  Byte 4  SCLDIR_BYTES_ENTRY (32 bit integer)

              Number of bytes  required  for  the  description  of  each  scaler
              module.  For the current version:  894 decimal.

           -  Byte 8  SCLDIR_OFFSET (32 bit integer)

              Number of bytes from the beginning of the scaler control block  to
              the  first  module  description.   For  the  current  version:  80
              decimal.

           -  Byte 12 SCLDIR_SIZE (32 bit integer)

              Number of bytes occupied by the entire scaler control block.

           -  Byte 16 SCLDIR_MAX_CHANNELS (32 bit integer)

              Number of channels per  module.   For  the  current  version:   32
              decimal.

           -  Byte 20 SCLDIR_CHANNEL_BYTES_ENTRY (32 bit integer)

              Number of bytes  required  to  describe  each  channel.   For  the
              current version:  28.

           -  Byte 24 SCLDIR_CHANNEL_OFFSET (32 bit integer)

              The number of bytes required to describe a module and that precede
              the channel descriptions for that module.

           -  Byte 28 SCLDIR_TIME (24 character ascii DD-MMM-YYYY HH:MM:SS.CC)

              The time at which the scaler information was written to tape.
        Daphne Tape Format                                                 Page 14
        Scaler Data Block                                           10 August 1992


           -  Byte 52 SCLDIR_VERSION (32 bit integer) Current version is 1.

           -  Bytes 56 through 79 are filler

           -  Byte 80 Beginning of first module description


          The module header:

           -  Byte 0  SCL_CONTROLLER (32 bit integer)

              This is a number used internally  by  Daphne  to  identify  scaler
              types.

           -  Byte 4  SCL_CRATE (32 bit

              The crate number in which the module is  located.   Crate  numbers
              may be between 0 and 255 but are usually 1, 2, or 4.

           -  Byte 8  SCL_SLOT (32 bit integer)

              The slot number of the crate in which the module sits.

           -  Byte 12 SCL_READOUT (32 bit integer)

              If zero then this module is not  to  be  read-out  by  the  scaler
              read-out program.  If non-zero this indicates what strategy should
              be used for reading the module.  Thus the value  depends  on  what
              model of scaler it is.

           -  Bytes 16 through 27 are filler

          The description of the first channel of a module  immediately  follows
          the module header.


           -  Byte 0  SCL_FILLED_FLG (32 bit logical)

              If the low order bit of this word is clear than  this  channel  is
              considered inactive and is ignored by the scaler read-out program.
              If the bit is set then this channel of the module will be read-out
              periodically.

           -  Byte 4  SCL_COUNT (32 bit integer)

              The number of counts recorded by this channel of the module.  This
              is a 32 bit counter.

              The scaler read-out program assumes that the scalers count  module
              2**24  (16,777,216).   When  the  scaler read-out program realizes
              that the current value of the scaler is less  than  the  preceding
              value it increments the high order 8 bits of the 32 bit counts and
              updates only the low order 24 bits.
        Daphne Tape Format                                                 Page 15
        Scaler Data Block                                           10 August 1992


           -  Byte 8  SCL_TITLE (12 character ascii)

              This is the name assigned by the user to the scaler  channel.   It
              is blank filled to 12 characters.

           -  Bytes 12 through 27 are filler

        Daphne Tape Format                                                 Page 16
        Scaler Data Block                                           10 August 1992



                  Block number 4 (00000004), 3776 (0EC0) bytes 

                  C        8        4        0 
           0000000A 00000050 0000039C 20203144 D1  ....P....... 000000 
           +------^ +------^ +------^ -------^ 
           |        |        |        buffer ID and 2 character filler 
           |        |        bytes required for each module and its channels 
           |        number of bytes from start of block to first module description 
           number of 512 byte pages allocated for the scaler control block 

           4A2D3033 0000001C 0000001C 00000020  ...........30-J 000010 
           +------^ +------^ +------^ -------^ 
           |        |        |        number of channels per module 
           |        |        number of bytes required for each channel description 
           |        number of bytes from start of module desc to 
           |        first channel description 
           time at which scalers were written to tape MM-DDD-YYYY HH:MM:SS.CC 

           38303A34 343A3830 20363839 312D4C55 UL-1986 08:44:08 000020 
           00000000 00000000 00000001 0034362E .64............. 000030 
           +------^ +------^ +------^ -------^ 
           |        |        |        last 3 bytes of time and one byte of filler 
           |        |        version number 
           filler   filler  

           00000000 00000000 00000000 00000000 ................ 000040 
           filler   filler   filler   filler 

           00000002 00000002 00000001 00000004 ................ 000050 
           +------^ +------^ +------^ -------^ 
           |        |        |        scaler type (4 is a Lecroy 4434) 
           |        |        crate 
           |        slot 
           readout type 

           FFFFFFFF 00000000 00000000 00000000 ................ 000060 
           +------^ +------^ +------^ -------^ 
           |        filler   filler    filler 
           first channel (channel 0) is active 

           20202020 20202020 3143534D 00000000 ....MSC1         000070 
           +------------------------^ -------^ 
           |                          count is zero 
           name of channel is "MSC1" with 12 characters blank filled 

           00000000 FFFFFFFF 00000000 00000000 ................ 000080 
           +------^ +------^ +------^ -------^ 
           |        |        filler   filler 
           |        second channel is active 
           count is zero 

           00000000 20202020 20202020 314C4554 TEL1        .... 000090 
           +------- +------------------------^ 
           |        name is "TEL1" 12 characters blank filled 
           filler 

           324C4554 00000000 FFFFFFFF 00000000 ............TEL2 0000A0 
        Daphne Tape Format                                                 Page 17
        Scaler Data Block                                           10 August 1992


           00000000 00000000 20202020 20202020         ........ 0000B0 
           20202020 334C4554 00000000 FFFFFFFF ........TEL3     0000C0 
           FFFFFFFF 00000000 00000000 20202020     ............ 0000D0 
           20202020 20202020 344C4554 00000000 ....TEL4         0000E0 
           00000000 FFFFFFFF 00000000 00000000 ................ 0000F0 
           00000000 20202020 20202020 3243534D MSC2        .... 000100 
           4E414843 00000000 FFFFFFFF 00000000 ............CHAN 000110 
           00000000 00000000 20202020 20202036 6       ........ 000120 
                   
                  <Remainder of block omitted> 

        Daphne Tape Format                                                 Page 18
        Table of DAQ codes of General Interest                      10 August 1992


          8  Table of DAQ codes of General Interest


          aaav    integer         format is ddmmyy                 
          fstp    logical         force stop 
                                  Set if $STP used the /FORCE flag to stop acquisiton 
          otpr    integer         out tape record size 
                                  specifies the size of buffer (in bytes) to be 
                                  used by the poutput tape process 
          scld    integer         scaler_delay 
                                  when scalers are used gives the number of seconds 
                                  to wait between reading scalers 
          sclm    integer         maximum number of scaler modules defined 
          beam    character 6     beam from $INZ command 
          comm    character 60    comment from $INZ command 
          dtti    character 23    date and time of acquisition start  
                                  format is dd-mmm-yyyy hh:mm:ss.cc 
          ener    character 6     energy from $INZ command 
          evss    integer         event structure size (in units of 512 byte pages) 
          expn    character 20    experiment name from $INZ command 
          phys    character 20    physicist name from $INZ command 
          runn    character 6     run number from $INZ command 
          targ    character 6     target from $INZ command 
          vers    character 6     Daphne version - format is yymmdd (?) 
        Daphne Tape Format                                                 Page 19
        Table of Buffer Type Codes                                  10 August 1992


          9  Table of Buffer Type Codes



          An asterisk ("*") indicates control blocks that can appear on a Daphne 
          data tape at the present time (August '86). 

                  Code    Defined By      Short Description 
                  ----    ----------      ---------------------------------- 
                  A0*     ETAPE.FOR       First record of an event mode file 
                  A1*     ETAPE.FOR       First record of a dump mode file 

                  B0*     DAQ.INC         Data acquisition parameters 
                  B1*     EVSDEFS.INC     Event structure
                  B2      W2DDEFS.INC     2-D Window directory 
                  B3      W2DDEFS.INC     Window address block 
                  B4      W2DDEFS.INC     Window corner block 
                  B5      SCPDIRDEF.INC   Scatter plot buffers 
                  B6      CONDDEFS.INC    Condition definitions 
                  B7      W1DDEFS.INC     1-D Windows 
                  B8      H1MDEFS.INC     1-D Maps 
                  B9      H2MDEFS.INC     2-D Maps 
                  BA      FIXDEFS.INC     User FIXed pt. constants 
                  BB      FLTDEFS.INC     User FLT pt. constants 
                  BC      CAMDEFS.INC     CAMAC module structure 
                  BD      LNZDEFS.INC     Linearizations directory 
                  BE      LNZDEFS.INC     Linearizations address block 
                  BF      LNZDEFS.INC     Linearizations corner block 

                  D0*     D0.INC          Event buffers 
                  D1*     SCLDIRDEF.INC   Scaler contents and definitions 

                  H1      H1DDEFS.INC     1-D Histogram, (1-Byte/channel) 
                  H2      H1DDEFS.INC     1-D Histogram, (2-Bytes/channel) 
                  H4      H1DDEFS.INC     1-D Histogram, (4-Bytes/channel) 
                  H5      H2DDEFS.INC     2-D Histogram, (1-Byte/channel) 
                  H6      H2DDEFS.INC     2-D Histogram, (2-Bytes/channel) 
                  H8      H2DDEFS.INC     2-D Histogram, (4-Bytes/channel) 
                  HA      H1DIRDEFS.INC   1-D Histogram Directory 
                  HB      H2DIRDEFS.INC   2-D Histogram Directory