CSC DCC Output Data Format

Data Format:  (Same for Slink and Gigabit Ethernet)

The DCC data are aligned in 64-bit words.  Each event is one SLINK package, but maybe several Gigabit Ethernet packages.  The Data include: two SLINK header words, DDU data load, FakeDDU data load, and two SLINK trailer words. For Sept/Oct. beam test, there will be only DDU data load for normal data taking.  There will be FakeDDU data load for DCC test.
Here is an sample event:

1   5f00 0065 30fc aebf       DCC-Slink Header 1 ---- Slink64 header format --
2   d900 0000 00e0 8597       DCC-Slink Header 2                     
3   5000 0065 0f40 0000         DDU1 Header 1  ----------------     
4   8000 0001 8000 8000         DDU1 Header 2                 | Refer
5   1010 0000 0201 0002         DDU1 Header 3                 | to
6   9308 93e4 9000 9065           DMB1 header 1 ------        | DDU
7   a365 a008 aff3 a004           DMB1 Header 2      | Refer  | for
8   423e 4228 4242 422f             DMB Data Load    | to     | Data
9   4236 422e 4259 42da                  :           : DMB    | Format
10   4251 42cd 4247 4236                 :           : Data   |
11   4243 422b 4236 422e                 :           : Format |
12   4235 4239 424d 42bd                 :           :        :
13   424f 42d3 4248 4230                 :           :        :
 :     :    :    :    :                  :           :        :
31   4252 42d5 4246 4232                 :           :        :
32   7fff 7802 700a 1a71                 :           :        :
33   4241 422a 4244 4234                 :           :        :
 :     :    :    :    :                  :           :        :
201   4241 4229 4237 4233                :           :        :
202   423c 422f 425c 42d5                :           :        :
203   4251 42d0 4249 4231                :           : Refer  :
204   4246 422d 4238 4232                :           : to     :
205   423d 4234 4252 42d3                :           | DMB    :
206   424f 42d6 4245 4232           DMB Data Load    | for    :
207   7fff 7000 780c 66ac           DMB Data Load    | Data   :
208   fff3 f018 f07f f3e4         DMB1 trailer 1     | format :    
209   e000 e000 e000 efff         DMB1 trailer 2 -----        :
210   9308 93e4 9000 9065         DMB2 Header 1  -----        :
211   a365 a008 aff3 a004         DMB2 Header 2      | Refer  :
212   423e 4228 4242 422f           DMB Data Load    | to DMB :
213   4236 422e 4259 42da                :           | for    :
214   4251 42cd 4247 4236                :           : Data   :
215   4243 422b 4236 422e                :           : Format :
216   4235 4239 424d 42bd                :           :        :
 :     :    :    :    :                  :           :        :
406   423c 422f 425c 42d5                :           :        :
407   4251 42d0 4249 4231                :           :        :
408   4246 422d 4238 4232                :           |         |
409   423d 4234 4252 42d3                :           | Refer   | Refer
410   424f 42d6 4245 4232                :           | to DMB  | to DDU
411   7fff 7000 780c 66ac           DMB Data Load    | for     | for
412   fff3 f018 f07f f3e4         DMB2 Trailer 1     | data    | Data
413   e000 e000 e000 efff         DMB2 trailer 2 ----- format  | Format
414   8000 ffff 8000 8000       DDU1 trailer 1                 |
415   1010 0000 0201 0002       DDU1 Trailer 2                 |
416   a000 019e 0000 0000       DDU1 trailer 3 -----------------
417   d865 d10c d865 d10c       Start of FakeDDU Data ----------
418   9065 9000 9065 9000         DMB3 header1  ------         | Just
419   93e4 9308 93e4 9308         DMB3 header1       | Refer   | to fake
420   a004 aff3 a004 aff3         DMB3 header2       | to DMB  | DDU
421   a008 a365 a008 a365         DMB3 header2       | for     | input
422   422f 4242 422f 4242           DMB Data Load    | data    | to test
423   4228 423e 4228 423e           DMB Data Load    | format  | DCC
424   42da 4259 42da 4259                :           | The     |
425   422e 4236 422e 4236                :           : 3rd,4th | It can
426   4236 4247 4236 4247                :           : words   | supply
427   42cd 4251 42cd 4251                :           : repeat  | redundant
428   422e 4236 422e 4236                :           : 1st,2nd : check
429   422b 4243 422b 4243                :           : words   : on DMB
430   42bd 424d 42bd 424d                :           :         : Data
431   4239 4235 4239 4235                :           :         :
 :     :    :    :    :                  :           :         :
813   42d0 4251 42d0 4251                :           :         :
814   4232 4238 4232 4238                :           :         :
815   422d 4246 422d 4246                :           : Refer   : FakeDDU
816   42d3 4252 42d3 4252                :           : to DMB  : Data to
817   4234 423d 4234 423d                :           : for     : test
818   4232 4245 4232 4245                :           | Data    | DCC
819   42d6 424f 42d6 424f                :           | Format  |
820   66ac 780c 66ac 780c           DMB Data Load    |         |
821   7000 7fff 7000 7fff           DMB Data Load    | 3rd,4th |
822   f3e4 f07f f3e4 f07f         DMB3 trailer1      | words   |
823   f018 fff3 f018 fff3         DMB3 Trailer1      | repeat  |
824   efff e000 efff e000         DMB3 trailer2      | 1st,2nd |
825   e000 e000 e000 e000         DMB3 trailer2 ------ words --|
826   efff 8000 0000 800b     DCC-slink trailer1
827   af00 033d a1e8 f197     DCC-slink trailer2 --- SLINK64 trailer format
 

! For most of the Sept/Oct. Beam test, there will be only DDU data, there will be no fake_DDU data. !

Here you can find the detailed discription of DCC-slink header1 and trailer 2 as defined by CMS as common data format, Follow the link to "DAQ/FE INTERFACING GUIDE", then link to "COMMON DATA FORMAT".  If you need check the CRC-16, contact Stan for the code.  Or you can use SLINK receiver hardware checking.

(Header 1: 5XYY,YYYY,ZZZW,WW5F
                  X: 1 for normal trigger, 2 for calibration
                  YYYYYY: 24-bit Event number counter (L1A number counter)
                  ZZZ: 12-bit beam crossing counter
                  WWW: 12-bit Slink ID
 Trailer 2: AFXX,XXXX,YYYY,ZZW3
                 XXXXXX: 24-bit package (in 64-bit) word count
                 YYYY: 16-bit CRC (USB, including header and trailer)
                 ZZ: Event summary: L1A, DUMPDATA, SLINKSTOP, FIFO_IN_USE(5-1)
                 W: TTS status, 0 for not_implemented    )


 DCC-slink header 2: D9XX,XXXX,XXYY,YYZZ

   XXXXXXXX: 32-bit orbit counter number
   YYYY: FIFOs status: Slink_FIFO_Status[4:0], IN_FIFO_PAEs[5:1], IN_FIFO_EMPTY[5:1], dummy bit
   ZZ: Bits 7,6,5,4,2 to indicate available DDU. For slink0, the DDU slots are 5, 12, 4, 13, 3 (same as Fifo_in_use[4:0]); for slink1, the DDU slots are 9, 7, 10, 6, 11 (same as FIFO_in_use[9:5]). Bit3 is set to 0, as the last header word, bit 1 and bit 0 no use (current value 11)

DCC-Slink trailer 1: EFZZ,XXXX,XXXX,XXYY
  XXXXXXXXXX: DDU data status, 8 bit each
  YY: FIFO readout timeout status: TimeOut_Fifo[5:2], '1', TimeOut_FIFO[1], Dummy[2:1]
  ZZ: Time used to readout the current event.  This is a coded 8-bit timer.  'a b c d e f g h', readout time is: (bcdefgh)*(16**a)*0.41us.

For CFEB data format, refer to CFEB data format .

For DAQMB data format, refer to DAQMB production data format .

For DDU data format, refer to DDU data format


Back to Gu work page

Feb. 1, 2006: Add the Header 2 'ZZ' for available DDU