HP PCL/PJL reference - Printer Job Language Technical Reference Manual
EN Status Readback Commands 7-35
Using Unsolicited Device Status
The following example enables unsolicited status with the verbose 
option. The printer response indicates that the printer is open.
<ESC>%-12345X@PJL <CR><LF>
@PJL USTATUS DEVICE = VERBOSE<CR><LF>
<ESC>%-12345X
A sample HP LaserJet 4 printer response for unsolicited device status 
is shown here. For other printers, responses may vary.
35
(35-000 to 35-999)
Messages indicating that operator intervention may be required. 
The printer stays online and continues printing, with the potential 
for reduced capability. Data may be lost.
40
(40-000 to 40-999)
Messages indicating that operator intervention is required. 
Printing halts until the condition is resolved. Examples include 
paper jam, out of paper, and printer open conditions.
41
(41-000 to 41-999)
This category of messages indicates a foreground paper mount. 
These conditions occur when paper is out and there is no 
alternate paper source available that is loaded with the correct 
paper size. The printer is offline under these conditions.
42 and 44
(42-000 to 44-999)
These status codes indicate paper jam errors and their 
associated error codes and control panel display strings.
43
(43-000 to 43-999)
Messages indicating PJL error codes and corresponding control 
panel display strings for optional (external) paper handling 
devices.
50 
(50-000 to 50-999)
Hardware errors. Examples include memory errors and fatal print 
engine errors.
Status Category Description
@PJL USTATUS DEVICE<CR><LF>
CODE=40021<CR><LF>
DISPLAY="12 PRINTER OPEN"<CR><LF>
ONLINE=FALSE<CR><LF>
<FF>










