Introduction To EPICS

Ned D. Arnold
May 1996

Table of Contents

EPICS Introduction

What is EPICS(1)?

See also ...

EPICS - An Architecture

Architecture and Tools

EPICS - Supported Hardware

EPICS - Software Tools (Channel Access)

The Software Bus

Architecture and Tools

EPICS - Software Tools (IOC)

IOC Internals

Database Record Types by Category

Analog Input Calculation Analog Output
Binary Input PID Binary Output
Muli-bit Binary Input Signal Select Multi-bit Binary Output
Digitized Analog Input Data Compression Stepper Motor
State Subroutine Timing Signal
String Input Fanout Permissive
Long Input Histogram String Output
Pulse Counter Long Output
Pulse Train
Pulse Delay

Analog Input Record

struct aiRecord  {
  /* start of ai specific fields */ 
  double  val;  /* Current EGU Value */
  struct link  inp;  /* Input Specification */
  short  prec;  /* Display Precision */
  unsigned short  linr;  /* Linearization */
  float  eguf;  /* Engineer Units Full */
  float  egul;  /* Engineer Units Low */
  char  egu[16];  /* Engineering Units */
  float  hopr;  /* High Operating Range */
  float  lopr;  /* Low Operating Range */
  float  aoff;  /* Adjustment Offset */
  float  aslo;  /* Adjustment Slope */
  float  smoo;  /* Smoothing */
  float  hihi;  /* Hihi Alarm Limit */
  float  lolo;  /* Lolo Alarm Limit */
  float  high;  /* High Alarm Limit */
  float  low;  /* Low Alarm Limit */
  unsigned short  hhsv;  /* Hihi Severity */
  unsigned short  llsv;  /* Lolo Severity */
  unsigned short  hsv;  /* High Severity */
  unsigned short  lsv;  /* Low Severity */
  double  hyst;  /* Alarm Deadband */
  double  adel;  /* Archive Deadband */
  double  mdel;  /* Monitor Deadband */
  double  lalm;  /* Last Value Alarmed */
  double  alst;  /* Last Value Archived */
  double  mlst;  /* Last Val Monitored */
  double  eslo;  /* Rawto EGU Slope */
  long  roff;  /* Raw Offset */
  caddr_t  pbrk;  /* Ptrto brkTable */
  short  init;  /* Initialized? */
  short  lbrk;  /* LastBreak Point */
  long  rval;  /* Current Raw Value */
  long  oraw;  /* Previous Raw Value */

EPICS - Software Tools (Application Developer)

EPICS - Software Tools (Extensions)

Usually Channel Access Clients that need data from the IOCs or have data for the IOCs

An EPICS Application

EPICS - A Collaboration

Collaborators (as of 5/1/96)

Colliders Detectors Commercial
The_Advanced_Photon_Source (ANL) Halls_A,_B,_and_C_Slow_Controls (CEBAF) The High Power Laser Experiment (Boeing)
The Advanced Light Source (LBNL) Advanced Light Source Beamlines (partial) (LBNL) Wafer Fabrication Plant (AMD)
The Tesla Test Facility (DESY) Gammasphere (LBNL) Liquefied Nature Gas Plant (Baltimore G&E)
The Continuous Electron Beam Accelerator Facility Advanced Photon Source Beamlines (ANL) Tunnel Fire Ventilation Test Program (DOT/Bechtel-Parsons-Brinkerhoff)
The Bates Linear Accelerator (MIT) The PHENIX detector system for RHIC Slow Controls (BNL/LANL) Flexible Manufacturing Facility (Allied Signal)
RF for Next Linear Collider (SLAC) The STAR detector system for RHIC Slow Controls (Creighton/U. Wash/Kent State/UCLA/LBNL) Wastewater Treatment (Western Lake Superior Sanitary District)
DAHRT (LANL) The Biotechnology Beamline (SSRL) Potable Water Distribution (St. Louis County)
The Advanced Free Electron Laser (LANL) The BaBar detector for B-factory Slow Controls (SLAC/LBNL) Compressor Control (Baltimore G&E)
The HERA cryogenic plant (DESY) Structural Biology Research Group (Riken) GM Fuel Cell Program (LANL)
The Intense Pulsed Neutron Source (ANL) NASA Langley (wind tunnels) Plant Simulation (Knolls)
Free Electron Laser (Budker INP Flight Simulation (JPL)
The Tesla Test Facility Injector (SACLAY) Telescopes Fuel Depots (US Navy)
Racetrack Microtron (U/Ala) The Gemini 8-M Telescope (AURA) Product Storage/Movement Facility (Citgo)
The Free Electron Laser Program (Duke) Kitt Peak Observatory (NOAO) Ground Tracking Station (NASA Canberra)
The Heavy Ion Fusion Test Stand (LBNL) The United Kingdom Infrared Telescope upgrade (JAC) Well Head/Extraction (Saphania Oil Field)
RF and feedback for B-factory (SLAC) The William Herschel Telescope/WFFOS instrument (INGT)
The Average Power Laser Experiment (LANL) The Keck II Telescope (CARA)
Advanced Light Source (partial) (LBNL)
National Laboratory for High Energy
Physics (KEK)
Berlin Electron Synchrotron Light Source (BESSY II)
Microtron (University of Athens)

Suppose I wanted to ...


Reference: Overview of the Experimental Physics and Industrial Control system: EPICS by Steve Lewis, LBL
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