Protocols | CTTT | L3

Media: fiber optic, GLINK
Record Length: fixed

  19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
1 VRB START Header Length #Dwords MSb #LVDS Links
2   Header Format Object Format #Dwords LSb
3   Tick Data Type
4   Turn
5   0x00 Firmware Version
6   0x0000
:   Input Link Data Block
(112 frames)
119   Data Type Tick
120 VRB END Vertical Parity

Field Definitions

note: empty cells will contain zeros
VRB START     = "0101"
Header Length = 0x03
#Dwords MSb   = number of data words (upper nibble) = 0
#LVDS Links   = 8 
Header Format = Header Format, "010"
Object Format = Object format, "00001"
#Dwords LSb   = The number of data words (lower byte) = 112 = 0x70
Tick          = The accelerator bunch crossing number, range 1-159
Data Type     = 0x04
Turn          = The accelerator turn (revolution) number, range 0-65535

The Input Link Data Block contains eight CTOC L1 records as follows: "0000"+link0 frame1 bits[27:16] link0 frame1 bits[15:0] "0000"+link0 frame2 bits[27:16] link0 frame2 bits[15:0] ... "0000"+link9 frame7 bits[27:16] link9 frame7 bits[15:0] Vertical Parity = odd parity calculated over frames 1-119 VRB END = "1010" Firmware Version = this is the same byte that is reported back through the status bits. This number should be >= 26.

Revision History

2 Nov 2005: created JTO
3 Jan 2006: added parity links
2 Jun 2006: update for standard L3 sender code: frame 6 empty,
            remove minor version field, real vertical parity,
            range on the tick number is now 1-159, not 0-158!

jamieson@fnal.gov
Last modified: Fri Jun 2 10:16:38 2006