HP PCL/PJL reference (PCL 5 Printer Language) - Technical Reference Manual Part II

EN HP-GL/2 Commands and Syntax 17-11
4 Clamped Real—A number with an integer portion from –32,768
to 32,767; you are assured of at least 6 significant digits
(including integer and fractional portion). You may omit the
decimal point when no decimal fraction is specified. Sending a
number outside this range does not cause an error, but the
number is “clamped” to the limits of the range. For example, the
printer treats all numbers above 32,767 as 32,767.
Certain commands have parameters which are restricted to a
smaller range. These ranges are listed in the parameter tables
for each command. Sending a number outside the reduced
parameter range may produce unexpected results.
5 Label—Any sequence of characters. In the HP-GL/2 language,
text is described using the term “label.” Refer to the Label (LB)
command in Chapter 23 for a complete description.
Note Numbers within the above-mentioned ranges do not cause errors;
however, the range may exceed the printer’s physical printing area.
Numbers that move the pen position outside the effective window
result in image clipping. This topic is discussed in more detail later
in this chapter under “The Vector Graphics Limits.”
When you see the term “current units” in a parameter table, the unit
system of that parameter depends on whether scaling is on or off.
When scaling is on, the units are user-units; when scaling is off, the
units are plotter units (described under “Units of Measure” later in
this chapter).
Notes The printer cannot use exponential format numbers (for example,
6.03E8). If you are using a computer or language that uses the
exponential format, you must use integer variables or a formatting
technique to output fixed-point real numbers.
Parameter values less than the range maximum are passed by the
parser; these values may subsequently be unscaled into resolution
units (e.g. 7200 units-per-inch) that exceed the device-dependent
internally representable number range. If this occurs, the device
enters a LOST mode; all relative drawing commands are ignored until
a command is received which specifies an absolute move to a point
within the internally representable number range.