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

EN Status Readback Commands 7-7
If a printer language-specific variable is not available because that
printer language is not installed or is invalid, or if a port-specific
variable is not available because that port is not supported, the
command will return an appropriate error code if USTATUS
DEVICE=VERBOSE is enabled.
Note The LPARM : personality option must be used when requesting
printer language-specific information.
The IPARM : port option must be used when requesting port-specific
information.
Example: Using INQUIRE to Request Feature Settings
This example requests the current print environment settings for RET,
PAGEPROTECT, RESOLUTION, PERSONALITY, and TIMEOUT.
The printer response for this example is listed below.
<ESC>%-12345X@PJL <CR><LF>
@PJL COMMENT ***Inquiring About <CR><LF>
@PJL COMMENT Environment Settings*** <CR><LF>
@PJL ECHO 02:18:23.9 05-30-92 <CR><LF>
@PJL INQUIRE RET <CR><LF>
@PJL INQUIRE PAGEPROTECT <CR><LF>
@PJL INQUIRE RESOLUTION <CR><LF>
@PJL INQUIRE PERSONALITY <CR><LF>
@PJL INQUIRE TIMEOUT <CR><LF>
<ESC>%-12345X
For the HP LaserJet 4 printer, a sample printer response for this
example is as follows. Other PJL printers may respond differently.