EarthLCD ezLED-3 Series, User Manual

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5.0 Command your ezLCD with EarthSEMPL
Your ezLCD-30x is really a computer and like all computers it has a language in which you can talk to
it in. The ezLCD-30x uses the simplest of languages, which we call
Earth Simple Embedded Macro
Programming Language , or EarthSEMPL for short. We will use the terms EarthSEMPL program
and macro interchangeably in this manual.
5.1 ezLCD-30x Grammar
The syntax or grammar for EarthSEMPL commands is:
COMMAND {PARAMETER1} {PARAMETER2}...{PARAMETERn}<CR>
EarthSEMPL source code is a free-form ASCII text-line-based language which allows arbitrary use of
white space (spaces or tabs) to format code, rather than column-based or text-line-based restrictions.
ASCII allows almost any editing program to be used for writing your code. Note: ezLCD commands
are not case sensitive (can be upper or lower case letters) except for the ‘ezLCD Upgrade’ command.
Comments may appear either at the beginning of the line or after a command and must be preceded by
a single apostrohe ( ‘ ) or the command
COMMENT .
In the syntax above,
COMMAND
is one of the commands from Appendix D .
The PARAMETER can be a number, string, index or comment. Between every COMMAND and
PARAMETER you must leave a space, comma or tab.
a) Numbers and indexes inputs are 16 bits and can be decimal, Binary (0b100110111) or Hex (0x3456
or 0h7E54). Any number over 16 bits will be truncated.
b) Strings can be any combination of ASCII characters and should be enclosed by a double quote
("String 1”). A string may also use the back slash as a lead in to an escape character sequence. Current
escape characters supported are;
\n Line Feed
\r Carriage Return
\” Double quote
For example to print a word in quotes on the string you would print “\”hello\””.
c) Comments start with single quote (') and continue until the end of the line <CR>. 'this is just a
comment
Note: OFF or ON can be used for most commands instead of 0 and 1 for readability.
Finally the <CR> represents a carriage return. Note that in your terminal program the carriage return is
sent when you press enter and is not shown on the screen. If you use a microcontroller it should send
the carriage return byte (13 decimal or 0D hex) after each command. The carriage return tells
EarthSEMPL to immediately execute the command you just typed. Your terminal program must send a
carriage return after each line of a command and when you write macros in a text editing program your
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