HP PCL/PJL reference - Printer Job Language Technical Reference Manual

EN Product-Specific Feature Support A-43
HP LaserJet IIISi Comments
The LaserJet IIISi printer implements the three PJL kernel
commands: ENTER, COMMENT, and the UEL command.
As with other PJL printers, the HP LaserJet IIISi printer performs
explicit printer language switching using the ENTER command. To
enable the printer for language switching, the SYS SWITCH control
panel setting must be set to ON. To select a default printer language
for implicit switching, set SYS = to the desired language (PCL or
PostScript) from the control panel. The LaserJet IIISi printer does not
perform context switching.
The HP LaserJet IIISi printer does not support any PJL status
readback commands, environment variable commands, or device
attendance commands.
For an example that uses the PJL features found in the
HP LaserJet IIISi printer, see the “Using the ENTER Command”
example in Chapter 4.