escputil is a command line utility which allows the user to perform a variety of maintenance tasks on Epson Stylus inkjet printers. These tasks include head alignment, head cleaning, nozzle check, printer identification, and retrieval of the ink level from the printer. In order for many of the escputil functions to work, the user must have read/write access to the raw printer device (typically /dev/lp0, /dev/usb/lp0, and the like). In general, these operations should be performed by the root user. As always, the user must insure that the directory containing the escputil utility is listed in the $PATH environment variable, or that the full path is specified on the command line. The examples in this section will assume the former. The escputil utility was designed for use ONLY with Epson Stylus inkjet printers supported by the Gimp-Print software. It is possible that damage MIGHT occur to your printer if this utility is misused or if it is used with a printer other than an Epson Stylus inkjet printer. It is the sole responsibility of the user to insure that this utility is suitable for the task at hand. In this section, specific examples of common usage will be presented. A summary of the command line switches can be found in the escputil(1) man page. Perhaps the most basic function performed by escputil is that of determining the amount of ink remaining in the printer. To do this, the user must know the name of the raw printer device. This is usually /dev/lp0 for a printer connected to the parallel port, or /dev/usb/lp0 for a printer connected to the USB. If there are multiple printers connected, one of them may be referenced as /dev/lp1 or perhaps /dev/usb/lp1. In the event of uncertainty, and if CUPS is in use, view the following URL with a web browser. At that URL, look for a line which reads "Device URI". The author's USB printer is listed as "Device URI: usb:/dev/usb/lp0". For this example, assume that the raw printer device is a USB printer specified as /dev/usb/lp0. To get the ink level for this printer, issue this command and notice the output. The user would substitute their own raw printer device for the one shown in the example after the "-r" switch. Notice that the printout shows the percent of ink remaining for each color of the author's Epson Stylus Photo 870. When the ink levels get too low, print quality will suffer. In the author's personal experience, ink levels approaching 10% begin to cause print quality degredation, but this will vary depending on the precise printer model. What? The example above did not work? An error message was printed? What does it mean? There are several possibilities, depending on the specific error message. If the error message is "Invalid argument" (see following example), the problem is that the kernel is not configured with the CONFIG_PRINTER_READBACK option enabled. Another possibile cause for error is that the raw printer device does not have both read and write permission for the user attempting to access the device. In this case, the error message will read "Permission denied". A final possibility is that the raw printer device specified is incorrect, in which case the error message will read "No such device". On an inkjet printer, there are several small holes on the bottom of each ink cartridge through which the ink must flow smoothly in order to create high quality images on paper. If these holes become clogged, the printed image will show small gaps where there should have been ink. One can easily test for the existence of this condition by running a nozzle check. One need not be the root user to issue this command. Note that as shown, the command will print a nozzle test pattern on the default printer. If there are multiple printers present, the desired printer must be specified with an additional "-P printer_name" switch, where "printer_name" is the name of the desired printer. The printer will print a series of black (and colored) slanted lines on the paper. Observe these lines carefully. If there are gaps or spaces in these lines, then the corresponding nozzle is clogged and the print head must be cleaned. However, if there are no gaps, the nozzles are clean. If the printed output is showing gaps where there should have been ink, it is likely that one or more nozzles are clogged and the print head is in need of cleaning. One can verify this by first running a nozzle check and looking for gaps in the printout. To clean the print head, issue the following command. One need not be the root user to issue this command. Note that as shown, the command will clean the print head on the default printer. If there are multiple printers present, the desired printer must be specified with an additional "-P printer_name" switch, where "printer_name" is the name of the desired printer. Nothing will be printed on the paper. The printer will make some noise as it cleans the print head. Wait until the printer is finished cleaning the print head. Afterwards, execute another nozzle check and insure that the print head is indeed completely clean. Note that the process of cleaning the print head causes ink consumption, so do not clean the print head any more than necessary. For severely clogged nozzles, one may have to execute two or three cycles of nozzle check followed by a cleaning of the print head. If the printer had gone unused for a long time, the nozzles may be so clogged with dried ink as to be unrecoverable, in which case, the best course of action is to replace the ink cartridge. To insure the highest quality printouts, the print head must be in proper physical alignment. One can check and realign the print head by running this interactive alignment test. The escputil utility must know the exact printer model in use. One may specify the model on the command line using the "-m" switch, or the utility can detect the printer model if the user passes the "-r" switch and the name of the raw printer device. Note that an unprivileged user may use this command with the "-m" switch, but that (in general) the root user may only use the "-r" switch (which requires read/write access to the raw printer device). In the case of multiple printers in use, the "-P" switch is required to align the print head on the non-default printer. This utility lets you align the print head of your Epson Stylus inkjet printer. Misuse of this utility may cause your print quality to degrade and possibly damage your printer. This utility has not been reviewed by Seiko Epson for correctness, and is offered with no warranty at all. The entire risk of using this utility lies with you. Aligning the print head is an interactive process. The utility will print out a set of instructions and ask you for responses. Please read the instructions carefully and follow them precisely. A single sheet of paper will be needed (one can print on both sides to save paper). The following example illustrates the alignment process when issued by an unprivileged user who specified the printer model on the command line. (To obtain a list of printer models, issue the "escputil -M" command). Of course, your responses will vary and should be substituted for the responses shown in the following example. escputil -a -m 870 Escputil version 4.3.0, Copyright (C) 2000-2001 Robert Krawitz Escputil comes with ABSOLUTELY NO WARRANTY; for details type 'escputil -l' This is free software, and you are welcome to redistribute it under certain conditions; type 'escputil -l' for details. Please read these instructions very carefully before proceeding. This utility lets you align the print head of your Epson Stylus inkjet printer. Misuse of this utility may cause your print quality to degrade and possibly damage your printer. This utility has not been reviewed by Seiko Epson for correctness, and is offered with no warranty at all. The entire risk of using this utility lies with you. This utility prints 3 test patterns. Each pattern looks very similar. The patterns consist of a series of pairs of vertical lines that overlap. Below each pair of lines is a number between 1 and 15. When you inspect the pairs of lines, you should find the pair of lines that is best in alignment, that is, that best forms a single vertical line. Inspect the pairs very carefully to find the best match. Using a loupe or magnifying glass is recommended for the most critical inspection. It is also suggested that you use a good quality paper for the test, so that the lines are well-formed and do not spread through the paper. After picking the number matching the best pair, place the paper back in the paper input tray before typing it in. Each pattern is similar, but later patterns use finer dots for more critical alignment. You must run all of the passes to correctly align your printer. After running all the alignment passes, the alignment patterns will be printed once more. You should find that the middle-most pair (#8 out of the 15) is the best for all patterns. After the passes are printed once more, you will be offered the choices of (s)aving the result in the printer, (r)epeating the process, or (q)uitting without saving. Quitting will not restore the previous settings, but powering the printer off and back on will. If you quit, you must repeat the entire process if you wish to later save the results. It is essential that you not turn your printer off during this procedure. This procedure assumes that your printer is an Epson Stylus Photo 870. If this is not your printer model, please type control-C now and choose your actual printer model. Please place a sheet of paper in your printer to begin the head alignment procedure. Press enter to continue > Please inspect the print, and choose the best pair of lines in each pattern. Type a pair number, '?' for help, or 'r' to repeat the procedure. Pass #1> 8 Pass #2> 8 Pass #3> 8 Attempting to set alignment...succeeded. Please verify that the alignment is correct. After the alignment pattern is printed again, please ensure that the best pattern for each line is pattern 8. If it is not, you should repeat the process to get the best quality printing. Please insert a fresh sheet of paper. Press enter to continue > Please inspect the final output very carefully to ensure that your printer is in proper alignment. You may now: (s)ave the results in the printer, (q)uit without saving the results, or (r)epeat the entire process from the beginning. You will then be asked to confirm your choice. What do you want to do (s, q, r)? > s This will permanently alter the configuration of your printer. WARNING: this procedure has not been approved by Seiko Epson, and it may damage your printer. Proceed? Please confirm by typing 's' again that you wish to save the settings to your printer: > s About to save settings...succeeded! Your alignment settings have been saved to the printer. ]]> The following example shows what will happen if an unprivileged user attempts to align the print head by specifying the raw printer device on the command line. escputil -a -r /dev/usb/lp0 Escputil version 4.2.0, Copyright (C) 2000-2001 Robert Krawitz Escputil comes with ABSOLUTELY NO WARRANTY; for details type 'escputil -l' This is free software, and you are welcome to redistribute it under certain conditions; type 'escputil -l' for details. Attempting to detect printer model... Cannot open /dev/usb/lp0 read/write: Permission denied ]]> This next example illustrates the results obtained when the root user issues an alignment command while specifying the raw printer device. Note that the output is truncated and only shows the printer detection output. The printer identification command will query the printer for make and model information. This command requires read/write access to the raw printer device (generally limited to the root user). Substitute your own raw printer device in place of the /dev/usb/lp0 shown in the example. The output will vary depending on the precise printer model. For more detailed information about the command line switches accepted by the escputil utility, please consult the man page which is supplied with the Gimp-Print software. The user may also issue the "escputil --help" command to get a listing of supported command line switches. The command requires no special privileges to execute.