2001/10/02
CHAPTER 5 PJL - 38
7.
STATUS READBACK COMMANDS
7.1.
Introduction
Applications can request, by sending a PJL command to the printer, information such as the configuration
and status of the printer. The printer can be programmed to send back this information when requested and
also can send back voluntarily unsolicited information of its status such as cover open, off-line state, toner
empty, displayed prompt message on the LCD and other necessary information.
PJL Status Readback will help you to program the application to appropriately set the printer settings.
In this chapter, you can learn how to use PJL Status Readback in programming an application. The following
Status Readback Commands are described :
•
INQUIRE
... requests the information of the specified PJL Default setting (PJL Current Environment) set by
@PJL SET
or
@PJL RESET
command
•
DINQUIRE
... requests the information of the specified User Default setting (User Default Environment)
set by
@PJL DEFAULT
or
@PJL INITIALIZE
command or control panel
•
ECHO
... request the printer to send back to the host computer a comment for the purpose of
synchronization with each other in order to start communication
•
INFO
... requests a specified category of information from the printer
•
USTATUS
... gives the printer permission to send back unsolicited information.
•
USTATUSOFF
... turns off all unsolicited status information set by
USTATUS
Job Recovery is also described in this chapter.
7.1.1. Synchronization with the printer
The printer sends the status responses to the same I/O port as it received the request from. Therefore, in a
shared or network environment, if the I/O port was used by another user and the printer is still processing the
previous job, the printer may send a response of the status of the previous user's job against the request from
the current application. In order to make sure that an application can receive correct responses for its request,
it must synchronize itself with the printer by sending the
ECHO
command so as to be assured that the printer
is ready for communication to you.
7.1.2. Basic format of status readback responses
The printer sends its status information to the host computer in the following format :
•
starts with the
@PJL
prefix
•
ends with a <
FF
> character
•
All the data is in a readable ASCII format.
Each line in the PJL status responses is in the following format :
•
starts with a specific keyword
•
ends with <
CR
><
LF
>
For example, the readback response against the
@PJL DINQUIRE
is :
@PJL DINQUIRE [LPARM :
personality
]
variable
<CR><LF>
value
<CR><LF>
<FF>
The application must read all the data between the
@PJL
and <
CR
><
LF
> codes. If the application can not
understand the meaning of the lines, it must ignore them. Future printers may send currently unused
keywords.
Refer to each command description to learn about the format of responses from the printer.
Summary of Contents for HL-1250
Page 15: ...2001 10 02 CHAPTER 1 INTRODUCTION 1 CHAPTER 1 INTRODUCTION ...
Page 20: ...2001 10 02 CHAPTER 1 INTRODUCTION 6 ...
Page 21: ...2001 10 02 CHAPTER 2 PCL 1 CHAPTER 2 PCL PRINTER CONTROL LANGUAGE ...
Page 59: ...2001 10 02 CHAPTER 2 PCL 39 ...
Page 76: ...2001 10 02 CHAPTER 2 PCL 56 ...
Page 104: ...2001 10 02 CHAPTER 2 PCL 84 71 71 Lines picture Same as above ...
Page 109: ...2001 10 02 CHAPTER 2 PCL 89 ...
Page 123: ...2001 10 02 CHAPTER 2 PCL 103 ...
Page 131: ...2001 10 02 CHAPTER 3 PCL5C 1 CHAPTER 3 PCL5C ...
Page 149: ...2001 10 02 CHAPTER 4 HP GL 2 1 CHAPTER 4 HP GL 2 GRAPHICS LANGUAGE ...
Page 199: ...2001 10 02 CHAPTER 4 HP GL 2 51 ...
Page 204: ...2001 10 02 CHAPTER 4 HP GL 2 56 ...
Page 205: ...2001 10 02 CHAPTER 5 PJL 1 CHAPTER 5 PJL PRINTER JOB LANGUAGE ...
Page 248: ...2001 10 02 CHAPTER 5 PJL 44 ...
Page 263: ...2001 10 02 CHAPTER 5 PJL 59 ...
Page 264: ...2001 10 02 CHAPTER 6 EPSON 1 CHAPTER 6 EPSON FX 850 ...
Page 286: ...2001 10 02 CHAPTER 6 EPSON 23 LPRINT CHR 27 CHR 37 CHR 1 CHR 0 Select downloaded characters ...
Page 290: ...2001 10 02 CHAPTER 6 EPSON 27 Sample 12 ...
Page 292: ...2001 10 02 CHAPTER 6 EPSON 29 Sample 14 ...
Page 294: ...2001 10 02 CHAPTER 7 IBM PROPRINTER 1 CHAPTER 7 IBM PROPRINTER XL ...
Page 315: ...2001 10 02 CHAPTER 7 IBM PROPRINTER 22 ...
Page 316: ...2001 10 02 CHAPTER 8 BAR CODE CONTROL 1 CHAPTER 8 BAR CODE CONTROL ...
Page 326: ...2001 10 02 CHAPTER 9 HP GL 1 CHAPTER 9 HP GL GRAPHICS LANGUAGE ...
Page 353: ...10 5 2001 APPENDIX A COMPARISON LIST 1 APPENDIX A COMPARISON LIST ...
Page 391: ...10 5 2001 APPENDIX A COMPARISON LIST 39 AUTOSKIP ON OFF ON OFF ON OFF ON OFF ...