Protocols | CTQD | L2CFT

Media: fiber optic, GLINK
Record Length: variable, depends on the number of reported tracks

19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
VRB START Header Length #Objects
  Header Format Object Format Object Length
  Tick Data Type
  Turn
  FW Minor Version FW Major Version
  Status Bits
  Track Object(s)
  Data Type Tick
  Vertical Parity
  Pad Frame(s)
VRB END  

Field Definitions

note: empty cells will contain zeros

VRB START = "0101"

Header Length = 0x03

#Objects = the number of Track Objects, range 0-48

Header Format = Header Format, "001"

Object Format = Object format, "00001"

Tick = The accelerator bunch crossing number

Data Type = varies with quadrant: CTQD0 = 0xAF, CTQD1 = 0xB0, CTQD2 = 0xB1, CTQD3 = 0xB2

Turn = The accelerator turn (revolution) number

FW Minor Version = 0x00

FW Major Version = varies with the firmware version

Status Bits = Reserved for diagnostic data

Track Objects are 32 bits long, which requires two frames in this record.
Bits [31:16] go into the first frame and bits [15:0] go into the second frame. The 32 bits are defined as:

   [31]:    Track curvature bit
   [30:29]: Track PT bin ("00" = Max, "01" = High, "10" = Medium, "11" = Low)
   [28:26]: Extended PT information
   [25]:    Set to indicate a tight CPS cluster match
   [24]:    Loose CPS cluster match, unsupported and forced to "0"
   [23:21]: reserved, "000"
   [20]:    'R' bit. Set to indicate that the track matched to a CPS cluster outside the home sector
   [19:16]: The relative position of the cluster center within the home sector, range 0-15
   [15:10]: Track phi value, range 1-44
   [9]:     Set to indicate an isolated track
   [8:7]:   "00"
   [6:0]:   Trigger sector number, range 0-79

Vertical Parity = not supported, 0x0000

Pad Frame(s) = Pad frames are inserted in order to make the total record length a multiple of 8 frames.
This requirement is imposed by the VRB hardware.

VRB END = "1010"

Revision History

2 November 2005: created JTO
3 January 2006: added parity links


jamieson@fnal.gov
Last modified: Tue Jan 3 12:27:02 2006