Glossary of TermsΒΆ

sequencer
  1. The project that defines SNL and provides an implementation.
  2. The runtime library that supports execution of SNL programs.
cpp
The C preprocessor. Normally not a stand-alone program but part of the C compiler. Can be abused to preprocess SNL code, too, which is a constant source of compatibility problems.
snc
The SNL compiler. See Compiling SNL Programs.
SNL
State Notation Language. What this project is about.
assigned
The property of a variable or array element to occur in an assign clause in an SNL program.
PV
process variable
A mutable variable that is globally visible and accessible via some network protocol in a distributed control system, such as one based on EPICS.
CA
Channel Access
The EPICS network protocol, used to connect client programs to PVs hosted on a server.
EPICS
Experimental Physical and Industrial Control System. A set of tools and libraries for building large distributed soft real-time control systems.
state set
SNL jargon for finite state machine. A program may contain multiple state sets and each runs in its own thread.
true
Any non-zero value, as in C.
false
Zero, as in C.