Home » HP Manuals » Laser Printers » HP 2500 » Manual Viewer

HP 2500 HP PCL/PJL reference - Printer Job Language Technical Reference Manual - Page 215

Printer Status Readback Usage, Determining If Printer Status Readback is Available

Add to My Manuals
Save this manual to your list of manuals

Page 215 highlights

Printer Status Readback Usage Applications use printer status readback for two primary purposes (although there are other uses): printer driver configuration and monitoring device status. Since printer configuration does not change often (i.e., the amount of installed printer memory does not change frequently) using printer status readback to assist in initial configuration (or when the printer's configuration changes) is straightforward. If the application determines printer status readback is unavailable (discussed in the "Determining If Printer Status Readback is Available" section), the application can ask the user for the information instead of querying the printer. The other primary use for printer status readback is to allow applications to monitor the state of the printer. In particular, applications can inform the user when the printer requires intervention (e.g. fill paper trays). If the application enables unsolicited PJL device status, the printer will inform the application whenever the printer's status changes. Since the printer informs the application using unsolicited status, even when the printer is processing a print job from a different I/O interface, the application gets timely printer status information. If printer status readback is unavailable, the application will not be able to provide the user with current printer state information. Another use for printer status readback is to determine what volatile resources (e.g. soft fonts) are available in the printer right before a print job is sent to the printer. If an application optimizes the printer job using printer status readback (i.e., does not send soft fonts if the printer already has the font), then if printer status readback is unavailable, the application should assume worst case (i.e., the font is not in the printer) when generating print jobs. In summary, the application should be designed to take advantage of printer status readback, if available, but still function if it is unavailable. Determining If Printer Status Readback is Available If the application sends a PJL ECHO command (preceded by the Universal Exit Language command, of course) to the printer and receives the expected response, then the application can assume bi-directional communication with the printer is available and supported solicited status queries will be answered in a timely fashion. EN Programming Tips for Using PJL 11-21

Section	Page
Main Menu	3
Inside This Manual	5
Manual Organization	6
Related Documents	9
Manual Conventions	10
Contents	11
Introduction to PJL	15
What is PJL?	15
The Benefits of PJL	17
Who Should Use PJL?	17
Compatibility With Non-PJL Printers	18
PJL Command Syntax and Format	21
Introduction	21
Syntax Conventions	22
Format of PJLCommands	24
PJL Syntax Rules	25
Types of Variables	27
Processing Invalid Commands	29
Using PJL	31
Introduction	31
Overview of How Commands are Used	31
PJL Job Requirements	33
Some Sample PJLJobs	34
What's Next?	35
Command Groupings by Functionality	36
Kernel Commands	41
Introduction	41
Universal Exit Language (UEL) Command	42
ENTER Command	44
COMMENT Command	46
Methods of Printer Language Switching	47
Job Separation Commands	49
Introduction	49
JOB Command	50
EOJ Command	56
PJL Job Security	58
Password Protection of Default Feature Settings	58
Control Panel Lock	59
Disk Lock	59
Job Cancellation	61
Start of Job Notification	61
End of Job Notification	62
Job Cancellation Unsolicited Status	63
Environment Commands	65
Introduction	65
Print Environments	66
Changing Environment Settings	69
Environment Summary	70
PJL Reset Conditions	72
Key Points to Remember About Environments	74
PJL Environment Variables	75
General PJL Environment Variables	76
Port-Specific Variables (LaserJet4PJ Only)	90
PCL-Specific Variables	91
PostScript-Specific Variables	95
ESC/P-Specific Variables	96
Setting the Printer to a Desired State	98
DEFAULT Command	100
INITIALIZE Command	103
RESET Command	106
SET Command	109
Status Readback Commands	113
Introduction	113
Printer Status Requirements	115
Synchronizing Status Readback Responses	115
Format of Status Readback Responses	116
INQUIRE Command	117
DINQUIRE Command	122
ECHO Command	126
INFO Command	128
USTATUS Command	143
TIMED Variable	152
USTATUSOFF Command	154
Job Recovery	155
Sending the Initial Job	155
After Job Failure	156
Device Attendance Commands	159
Introduction	159
RDYMSG Command	160
OPMSG Command	163
STMSG Command	165
PJL File System Commands	169
Introduction	169
FSAPPEND Command	171
FSDIRLIST Command	173
FSDELETE Command	175
FSDOWNLOAD Command	176
FSINIT Command	177
FSMKDIR Command	178
FSQUERY Command	179
FSUPLOAD Command	181
File System Example	183
Job Management	187
Introduction	187
HP LaserJet 8100 Printer	187
HP LaserJet 8500 Printer	191
Programming Tips for Using PJL	195
Introduction	195
PJL Services	196
Print Data Generators	197
Printer Utilities	199
Spoolers	205
Requesting Printer Status	212
Using Status Readback in a Multi-User System	212
Product-Specific Feature Support	223
Introduction	223
PJL Feature Support	224
PJL Environment Variable Support	228
HP LaserJet IIISi Comments	265
Comments about HP LaserJet Printers	266
LaserJet Printers with Reduced-Function Control Panels	273
Color LaserJet Printer Comments	274
HP DeskJet 1200C and 1600C Printer Family Comments	274
HP LaserJet 5Si/ 5SiMx/5Si Mopier Comments	278
HP LaserJet 5Si Mopier Comments	279
HP LaserJet 4000 and 5000 Series Comments	281
HP LaserJet 1100 Series Comments	283
HP LaserJet 2100 Series Comments	284
HP Color LaserJet 4500 Series Comments	285
HP LaserJet 8000 and 8100 Series Comments	286
HP Color LaserJet 8500 Series Comments	287
PJL Command Summary	289
Programming Examples	295
Introduction	295
PJL Status Codes	301
Status Code Groupings	301
Informational Messages (10xxx) *	302
Background Paper Loading (11xyy)	304
Background Paper Tray Status (12xyy)	306
Output Bin Status (15xxy)	307
PJL Parser Errors (20xxx)	307
PJL Parser Warnings (25xxx)	309
PJL Semantic Errors (27xxx)	310
Auto-Continuable Conditions (30xxx)	311
PJL File System Errors (32xxx)	313
Potential Operator Intervention Conditions (35xxx)	314
Operator Intervention Conditions (40xxx)	316
Foreground Paper Loading (41xyy)	319
Paper Jam Messages (LaserJet 5Si/5SiMx only) (42xyy)	320
Optional (External) Paper Handling Device Messages (43xyy)	322
LaserJet 4000 / 5000 Series Paper Jam Messages (44xyy)	323
Hardware Errors (50xxx)	324
Glossary	327
Index	335
Symbols	335
Numerics	335
A	335
B	335
C	335
D	335
E	336
F	336
H	336
I	336
J	337
K	337
L	337
M	337
N	337
O	337
P	338
Q	339
R	339
S	339
T	339
U	339
V	340

Match case Limit results 1 per page

Programming Tips for Using PJL 11-21

Printer Status Readback Usage

Applications use printer status readback for two primary purposes

(although there are other uses): printer driver configuration and

monitoring device status. Since printer configuration does not change

often (i.e., the amount of installed printer memory does not change

frequently) using printer status readback to assist in initial

configuration (or when the printer's configuration changes) is

straightforward. If the application determines printer status readback

is unavailable (discussed in the “Determining If Printer Status

Readback is Available” section), the application can ask the user for

the information instead of querying the printer.

The other primary use for printer status readback is to allow

applications to monitor the state of the printer. In particular,

applications can inform the user when the printer requires

intervention (e.g. fill paper trays). If the application enables unsolicited

PJL device status, the printer will inform the application whenever the

printer's status changes. Since the printer informs the application

using unsolicited status, even when the printer is processing a print

job from a different I/O interface, the application gets timely printer

status information. If printer status readback is unavailable, the

application will not be able to provide the user with current printer

state information.

Another use for printer status readback is to determine what volatile

resources (e.g. soft fonts) are available in the printer right before a

print job is sent to the printer. If an application optimizes the printer

job using printer status readback (i.e., does not send soft fonts if the

printer already has the font), then if printer status readback is

unavailable, the application should assume worst case (i.e., the font is

not in the printer) when generating print jobs.

In summary, the application should be designed to take advantage of

printer status readback, if available, but still function if it is unavailable.

Determining If Printer Status Readback is Available

If the application sends a PJL ECHO command (preceded by the

Universal Exit Language command, of course) to the printer and

receives the expected response, then the application can assume

bi-directional communication with the printer is available and

supported solicited status queries will be answered in a timely

fashion.