# Presentation: 820615

## SNS Timing System Overview

- Brian Oerter (BNL)

## SNS Timing System Components

- Line locked reference clock (LANL)
- GPS based stratum 1 time server & interface to the Rtdl
- Eventlink Master
- VME eventlink slave module (V124s)
- Fiber/electrical distribution
- RealTimeDataLink Master
- VME utility module (LANL)
- Eventlink Monitor
- Final design review held 7/31/01 at LANL

## Time of Day

- Navistar GPS satellite receiver
- Network time server
- Ethernet interface with NTP
- IRIG “B” output
- VME module w/IRIG input

## Time of day

**IRIG “B”**

**ETHERNET**

## 
Master
V123s VME encoder 
V101 input module (16 channels)
256 Events or triggers
64 hardware
192 software (FIFO)
Events Prioritized by position 
Expandable

- Master
- V123s VME encoder
- V101 input module (16 channels)
- 256 Events or triggers
- 64 hardware
- 192 software (FIFO)
- Events Prioritized by position
- Expandable

- Event Link System

## Event link System

- V124s (slave)
- Flexible triggering
- Recovers RF clock (< 1 ns PP jitter)
- Eight individually programmable channels
- Delayed triggers
- RF clock phase reset at start of cycle
- Provides VME interrupts
- imbedded interface (mps, instrumentation)

## Real Time Data Link

- Master
- V105s encoder module
- V106/206 input module
- IRIG “B” receiver module
- Operation
- Master transmits 24 bit data frames
- Up to 256 Frames (requires multiple chassis)
- V105s contains a list of the frames to be transmitted

## Real Time Data Link

- Utility module
- Receives Event link transmissions
- Generates VME interrupts on selected events
**Small** FIFO avoids missed events
- Receives RTDL transmissions
- All received frames are stored in local memory
- Monitors chassis voltage, fan status & air temp
- Interrupts IOC on environment fault
- Inputs for external interrupts to IOC
- IOC reset via RTDL
- Imbedded interface (mps, instrumentation)

## Eventlink Monitor

- Receives all events
- Filter allows selective event storage
- Internal timestamp counter
- Events stored in memory with timestamp

## Eventlink Monitor

- AGE                     233321  -183312
- AU3                     249989  -166644
- APP                     266659  -149974
- BSTR_PEAKER_0xB0        273924  -142709
- TANDEM_10HZ             289521  -127112
- B.F3_A5_TRIGGER         368571  -48062
- TANDEM_10HZ             389521  -27112
- AFR                     399971  -16662
- AT0                     416633  0
- SEB.F10_HS_STRT.RT      416634  1
- AGT.END_CAL&JAM.RT      416643  10
- AGN.MCR_TR_6.RT         416653  20
- AGN.MCR_TR_7.RT         416681  48
- AGN.MCR_TR_8.RT         416715  82
- AGN.MCR_TR_5.RT         416723  90
- AGN.MCR_TR_2.RT         416733  100
- AGN.MCR_TR_1.RT         416735  102
- AGN.MCR_TR_3.RT         416737  104
- AGN.MCR_TR_4.RT         416739  106
- EV-SPIN-UP              417783  1150

## Slide 11

## Hardware Status

- Eventlink
- Two VME chassis have been purchased and received
- Six V123s prototypes built
- Four distributed to member labs
- Two additional modules sent to ORNL
- 12 V101 built
- Four distributed to member labs
- Four installed in SNS master chassis
- Four additional modules sent to ORNL

## Hardware status (con’t)

- V124s
- Three prototypes built
- One sent to ORNL
- 10 pre-production modules on order
- 50 more units to be built this year
- Work remaining on Eventlink system
- Submit V123s changes to drafting & build 2 production modules.

## Hardware status (con’t)

- RTDL System
- GPS equipment has been received and installed
- 8 V105s built
- Four distributed to member labs
- Four additional modules sent to ORNL
- 12 V106s built
- Eight distributed to member labs
- Four additional modules sent to ORNL

## Hardware status (con’t)

- Work remaining on RTDL
- V206 (8 channel)
- Design in drafting
- Build 16 production modules
- Other work
- Build/Test eventlink monitor
- Complete design of 16 channel fanout
- Built production fanouts