Communication

1
Communication Control

• H.Evans Columbia U.
• Overview of FRC Functions
• Road Info STCs,TFCs
• Device Independent Data Format
• SCL STCs,TFCs,ZVC (c.f. MBT)
• L1 Info to other boards
• L2 Info to Buffer Control
• SCL Init
• L3 Buffers All (c.f. VRB)
• Define Standard L3 Buffer Unit
• Buffer Protocol
• Status/Mon. All
• Init / Busy / Error
• Monitoring Registers (c.f. MBT)

2
G-Link Conv (CFT)
FRC (road)
L1CTT
L3 FRC Road-Buff
FRC (buff-ctrl)
Roads L1-SCL
L1 Info
Buffer Control
L1 / L2
SCL Hub
SCL Mezz
FRC (scl)
Init / Busy / Error
ZVC
L2CTT MBT
3
Road Data Format

• Control Info Required with each word
• Valid Data
• End of Event
• CLK
• 3 Extra Bits for each word transferred

4
L1CTT Data Format
See M.Martin http//d0server1.fnal.gov/www/protoc
ols/
5
L1CTT Glossary (Abridged)

• Header
• P/N Some Trks w/ Pos/Neg Pt
• No. Ptx No. of Trks in Pt Bin x
• Data
• S Sign of Trk
• Pt Bin Pt Bin Number (0-3)
• Ext. Pt Bin-1 (1.5-3 GeV) A-Offset Bin-2 (3-5
  GeV) A-Offset Bin-3 (5-10 GeV) Pt-Info Bin-4
  (10- GeV) Pt-Info
• H/L Trk assoc w/ Hi/Lo PS Clust
• Err Transmission Errors
• R PS Clust assoc in adjacent sect
• PSC RA Rel. Addr of PS Clust
• Rel ? H-Layer Fiber Number
• Is Isolated Track
• eI Isolated Electron
• Trk Adr Address of 4.5o wedge of Trk

6
Serial Command Link

• Steal as much as possible from MBT
• see MBT TDR (ver. 5 - 5/24/99) http//macdrew.phys
  ics.umd.edu/dzero/trigger/mbt.html
• L1 Accept
• L1_TURN, L1_BX, L1_QUAL sent to
• STCs, TFCs, ZVC(?) as 1st element of Road Data
• FRC Buffer Control to request next Buffer
• L2 Accept
• L1_TURN, L1_BX, L3_TRAN_NO sent to
• FRC Buffer Control to initiate Buffer Transfer

7
SCL (cont.)

• SCL Init Sequence
• Command Implementation
• 1) FRC Rec Init from Hub mezzanine
• 2) FRC Send Init to all Card User pin
• 3) FRC INIT_ACK to Hub mezzanine
• 4) FRC Clear L1/L2_ERROR mezzanine
• 5) All Receive Init from FRC User pin
• 6) All Raise Local Busy VME stat reg
• 7) All Start Init Sequence wait until all Inputs
  are clear send Init Done signal
• 8) FRC Poll all Local Stat Regs VMEor Wait for
  local init_acks User pin
• 9) FRC Clear INIT_ACK mezzanine
• Have to be ready for SCL Init on any 132 ns SCL
  word !

8
Buffers and Control

• Steal from VRB / VRBC
• see ESE-SVX-950719 (7/1/99)http//www-ese.fnal.go
  v/eseproj/index/svxii/svxii.htm
• Possible System
• FRC(buff) acts as Buffer Manager for all L3
  Buffer Units in system
• sends same control signals to all Units
• basically Write to Buffer i L1 Acc Read from
  Buffer j L2 Acc
• All buffer number management at FRC
• control signals derived from L1/L2 SCL
• decouples SCL from rest of system(aside from
  road data)
• Use same L3 Buffer Unit on all cards
• simplifies I/O
• use L3 Buffer Unit on FRC ?
• Control Protocol a subset of VRBC

9
L3 Buffer Unit
Data Source
Buffer Controller
Data
Message
Busy/Error
16 evt
Data
Pointer
Cmd/Addr Decode RW
Route Count
Data
Enable/Reset/Busy/Error
Route Count
Count/Ovfl
Enable/Reset/Busy/Error
Data
C/O
Status Format/Xmit
VME VBD
FIFO full
Addr Error
Count / Status
10
VRB Buffer Protocol

• Messages
• 122(?) bit Field on Ext Ctrl Port
• Bits 11..8 Type 7..0 Value
• Control 1..0 Valid,CLK

11
Buffer Protocol (cont.)

• Status
• in VRB open collector TTL on J5/6
• OR of all modules

12
STT Control / Status

• Fast Status User pins
• Event-by-Event Comm. w/ Trigger
• Lines to FRC are OR of all boards
• SCL Init / Restart from FRC
• Busy / Error / Init Ack to FRC
• Each board must define
• Actions for Init / Restart(w/in guidelines of
  SCL Init Sequence)
• conditions for Busy / Error
• Monitoring VME Regs
• Steal from MBT (?)
• Use Standard Monitoring Registers
• same memory maps

13
FRC To Do List (from BU)

• Check for Truncation Scheme Biases
• Define Road Info Data Format
• Decide Where Reformatting of L1CTT Info will be
  Done
• Decide on Communications Medium
• Identify SCL Info Needed
• Define Data to L3
• Define Buffer Control Protocol
• Define Monitoring Data / Monitoring Control
• Long List of Internal FRC Decisions
• Done
• First Pass
• Still Pending