HP Color LaserJet 5500 Technical Reference Manual page 24

2-6 PJL Command Syntax and Format
The placement of white space in PJL commands depends
on its location within the command. Some white space is
required and some is optional:
White space is required between the @PJL prefix and
the PJL command name, and between the PJL
command name and command modifiers. For example:
@PJL OPMSG DISPLAY
@PJL ENTER LANGUAGE = personality
If white space is shown in any other place in the
command, it is optional (see the examples below).
If white space is not shown between two portions of a
command, white space is not allowed. An example is
between the optional carriage return and required line
feed character that terminate most commands.
For clarity, this manual consistently shows white space as
one blank space. The PJL language requirements are
shown in both examples below:
or