LCLS EPICS Record Naming Convention (First Proposal - No Longer in Effect)

EPICS Record Naming Convention

This page describes the EPICS database record naming convention for all LCLS records.

Contents:

Description

In order to limit the number of alias names required, naming is used that allows LCLS PVs to be used by SLC control system CA clients and also provides for simple translation from SLC control system names to PV names by the SLC-aware IOC. These names may also fit in more nicely with existing SLAC documentation tools.

The [ LCLS Linac Current Beamline Design Optics Files|http://www-ssrl.slac.stanford.edu/lcls/linac/optics] is a good reference when creating device names. The current primary, location, units for optics elements in the injector and sector 21 is here. The [ "How to Add an EPICS Process Variable"|http://www.slac.stanford.edu/grp/cd/soft/share/slaconly/how-to/add_pv.html] for ESD IOC applications is a good reference. A similar page for LCLS IOC applications needs to be written.

The SLC-aware IOC naming conventions are VERY strict, stricter than those for the SLC CA clients, and so drive the requirements:

PRIM:LOCA:UNIT:ATTRIBUTE

  1. All record names consist of exactly 4 parts separated by colons.
  2. All upper-case.
  3. First part (PRIM) indicates device type and is 1 to 4 characters. For records on SLC-aware IOCs that are used by the SLC control system, PRIM must be one of the SLC control system primaries.
  4. Second part (LOCA) is location and must be 4 characters, no more, no less. The first two characters must be non-numeric and the last two characters must be numeric.
  5. Third part (UNIT) is the device "unit" integer number between 1 and 9999 (with no leading zeros) and is unique for the specified PRIM and LOCA. It's like a simple serial number. For "one-of" items, use 1. When 2 values are needed for a unit number (ie, device 3 on girder 2), use a zero to separate (ie, 203). For devices on girders, the first part of the unit number is the girder number for the sector and the second part is the count of that device on the girder. The preference is for unit numbers no greater than 3 characters.
  6. Fourth part (ATTRIBUTE) is the device attribute and is 1 to 12 characters. In the SLC control system, attributes are known as secondaries.

IOC Micro Name List

Micro names for the existing SLC control system are listed in microname.dat file. All SLC-aware IOCs must be assigned a unique micro name which is then added to this file using the ESD [ "Adding a Micro to the SLC Control System"|http://mccdev.slac.stanford.edu/doc$database/how_to_add_micro.mem] procedure. A micro name is used as the location (LOCA) name in a record if the record is IOC-specific. Micro names for IOCs are listed in the LCLS production IOCs and LCLS development IOCs.

Record Name Examples

X Corrector, LINAC sector 21, IOC micro LM21, corrector 2 on girder 3 in sector 21, readback of magnetic field (ACT stands for actual)

BPM, LINAC sector 21, IOC micro LB21, BPM 1 on girder 2 in sector 21, position in the LINAC

Diagnostics tank, X-ray beamline front end enclosure, unit 1, HVPS voltage readback

Vacuum pneumatic gate valve, X-ray beamline near experimental hall hutch 1, unit 99, open/closed/transition/invalid state

Restart the SLC-aware interface via the exec task on BPM IOC micro LC28, LINAC sector 28

Primary (PRIM) List

Some of the following list of primaries are extracted from the SLC control system [ primary.dbs|http://www-mcc.slac.stanford.edu/ref_dbsfile/primary.dbs] file for devices that are SLC-Aware.

  1. Controlled Devices (SLC-Aware):
  2. Controlled Devices (non-SLC-Aware):
  3. Gated ADC Devices (SLC-Aware):
  4. Gated ADC Devices (non-SLC-Aware):
  5. Vacuum Gauges:
  6. Vacuum Valves:
  7. Vacuum Pumps:
  8. Other Devices:
  9. Subsystems and Groups/Collections:
  10. Controls Hardware:

Location (LOCA) List

  1. Gun and Injector
  2. LINAC and Beam Switchyard (BSY)
  1. LINAC-to-Undulator (LTU) and Undulator
  1. X-ray Transport and Optics Diagnostics (XTOD)

Xabc, where:

E = Front End Enclosure

N = Near Hall

F = Far Hall

T = Transport

X = non-specific (XTOD-wide)

1 to 3 for hutch

1 to 9 for section

0 for non-specific (area-wide)

C = Collimator

D = Diagnostic (tank)

I = Ion-chamber

1 to 3 for split beam line (tunnel) or vacuum station

0 = non-specific (hutch-wide or section-wide)

GA = Gas Attenuator

FL = FLipper Mirror

Mm = Mirror m (m=A, B, C)

XS = Xray Slit

Attribute (or Secondary) List

  1. Analog:
  1. IOC Attributes:
  1. Event Timing Attributes:
  1. Finite State (Digitals and Multibits):
  1. XTOD States:
  1. Strings and other record types:

::[ SLC-Aware IOC Home Page|http://www.slac.stanford.edu/grp/lcls/controls/global/sw/slc_ioc/] |
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Contact: Stephanie Allison
Last Modified: Feb 3, 2006