2470 High Voltage SourceMeter Instrument Reference Manual
Section 13: Introduction to TSP commands
2470-901-01 Rev. A /
May
2019
13-13
What is Lua?
Lua is a programming language that can be used with TSP-enabled instruments. Lua is an efficient
language with simple syntax that is easy to learn.
Lua is also a scripting language, which means that scripts are compiled and run when they are sent to
the instrument. You do not compile them before sending them to the instrument.
Lua basics
This section contains the basics about the Lua programming language to allow you to start adding
Lua programming commands to your scripts quickly.
For more information about Lua, see the
). Another source of useful information
is the
), created for and by users of Lua programming language.
Comments
Comments start anywhere outside a string with a double hyphen (
--
). If the text immediately after a
double hyphen (
--
) is anything other than double left brackets (
[[
), the comment is a short comment,
which continues only until the end of the line. If double left brackets (
[[
) follow the double hyphen
(
--[[
), it is a long comment, which continues until the corresponding double right brackets (
]]
) close
the comment. Long comments may continue for several lines and may contain nested
[[
. . .
]]
pairs.
The table below shows how to use code comments.
Using code comments
Type of
comment
Comment
delimiters
Usage
Example
Short
comment
--
Use when the
comment text fits
on a single line.
--Turn off the front-panel display.
display.lightstate = display.STATE_LCD_OFF
Long
comment
--[[
]]
Use when the
comment text is
longer than one
line.
--[[Display a menu with three menu items. If
the second menu item is selected, the
selection will be given the value Test2.]]
Function and variable name restrictions
You cannot use Lua reserved words and top-level command names for function or variable names.
Variable names must contain at least three characters.
The following table lists some of the Lua reserved words. If you attempt to assign these, the event
code -285, "TSP Syntax error at line x: unexpected symbol near '
word
' " is displayed, where
word
is
the Lua reserved word.
