M PE-SETTTNΓT METHOP AND APPARATUS FOR A SERIAL PRT TER
BAΓKΓ-ROT TND OF THF T VFNTTON
FIELD OF THE INVENTION The present invention relates to improvements in mode setting methods and apparatus for selecting and setting various operating parameters or "modes'' for a serial printer, such as an ink-jet or dot-matrix printer.
DESCRIPTION OF THE PRIOR ART
Conventional serial printers, such as ink-jet and thermal printers, are operable in a variety of different modes to provide e.g., different printer emulations, paper sizes, character fonts, image orientations, resolutions, etc. As a means for selecting a particular set of operating modes, many serial printers incorporate as many DIP switches as are required to define each operating mode and mode variation. Since each DIP switch is only capable of switching to either an "on" or "off" condition, in cases where there are more than two options for a particular operating mode, e.g. various language fonts, it is necessary to provide a relatively large number of DIP switches and combine their respective outputs in such a way as to make different choices possible. In serial printers, the number of DIP switches has been steadily increasing and, in order to make a single printer accommodate various models of host computers, some printers have as many as thirty DIP switches.
Other types of mode setting devices include a liquid crystal display on which the various mode options are displayed and selected. These displays are mounted on the printer housing at a location to be easily seen and, in order to display sufficient information to be useful, they tend to be relatively large in size.
As may be appreciated, a large number of DIP switches adds considerable expense to the printer manufacturing cost Moreover, such switches are space-consuming and, hence, are not well suited for use in a compact printer product Furthermore, as each DIP switch can function only as an "on/off" indicator, it is necessary to frequently refer to a printer manual for each setting.
While the use of a liquid crystal display (LCD) facilitates mode selection and setting, such displays are also expensive and space-consuming.
SUMMARY OF THE INVENTION
Regarding the above problems, the present invention has as an objective the provision of a serial printer mode setting apparatus which is inexpensive to produce and consumes no extra space on the printer housing.
Another object of this invention is to provide a more "user friendly" method of mode-setting in a serial printer.
The printer mode-setting apparatus of the invention is useful in all serial printers of the type having a movable carriage for scanning a printhead across a print-receiving member (e.g., a sheet of paper) in a direction perpendicular to the direction in which the print-receiving member is advanced during a printing operation to serially print pixels of one or more lines of image information. According to a preferred embodiment of the invention, such mode- setting apparatus comprises: (a) means for selectively printing on a print-receiving member positioned at a predetermined position relative to a printer housing, a listing of a plurality of printer modes, each of such printer modes having a plurality of options associated therewith;
(b) means for selecting one of said printer modes and printing the options associated therewith on said print-receiving member in a direction parallel to the direction of movement of said printhead;
(c) means for selectively moving the printhead carriage to a position in which a reference mark thereon is located opposite that of a printed option of interest; (d) means for producing an option-select signal; and
(e) means responsive to said option-select signal and to the position of said printhead for causing the printer to operate in a printer mode determined by tiie printed option located opposite the reference mark.
The mode-setting method of the invention basically comprises the steps of
(a) displaying on a print-receiving member positioned within the" printer a listing of the various printer modes for which certain options exist to alter r'r each mode ; ' ■ '
(b) selecting a particular printer mode from said listing and printing out on the print-receiving member in a direction parallel to the direction of movement of a printhead carriage, a listing of the options associated with the particular printer mode selected;
(c) moving the printhead carriage to a position in which a reference mark thereon is located opposite a desired option; and (d) producing an option-select signal when the printhead is positioned opposite a desired option.
The invention will be better understood from the ensuing detailed description of a preferred embodiment reference being made to the accompanying drawings.
BR TFF DESCR TPTTON OF THF. llR A WINKS FIG. 1 is a block diagram showing a preferred embodiment of a serial printer mode-setting apparatus according to the present invention;
FIG.2 is a perspective illustration of a serial printer of the type in which the invention is particularly useful;
FIG. 3 is an explanatory drawing showing an example of the manner in which various printer modes (parameters) are displayed on paper, as well as their respective selectable options;.
FIGS. 4-6 are flow charts illustrating the steps carried out by the microcomputer shown in FIG.l.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS Referring to FIGS. 1 and 2, FIG. 2 shows the exterior of a serial printer, in this case, an inkjet printer. In the rear part of printer body 1 is a platen roller 3 to which a print-receiving member, such as a sheet of plain paper 2, is automatically supplied by an automatic sheet-feeder (not shown). As roller 3 rotates, the print-receiving member is advanced in the direction of the arrow. A printhead carriage 4, equipped with a printhead (e.g., an inkjet head or thermal printhead), is positioned in front of platen roller 3. On command, head carriage 4 repeatedly scans the paper in a lateral direction, i.e. perpendicular to the direction of movement of the print-receiving member, while the printhead is energized to print information on the paper. For reasons explained below, the printhead carriage or, alternatively, the printhead itself, is provided with an arrow-shaped reference marker 5 on its upper surface.
Arranged on the top of the front part of body 1 is an operator control panel 6, which includes a set of key switches 7-11. Normally, these keys operate, respectively, to control power to the printer, to determine whether or not the printer is "on-line" (i.e., is operatively coupled to a host computer), to control paper feed, to select or deselect a character font or, in the case of an inkjet printer, to prime the printhead. However, as explained below, some of these same keys also serve, in accordance with a preferred embodiment of the invention, to select set or change the printer modes. For example, key 7 determines whether or not the printer is in a "mode-setting" mode, keys 8 and 9 selectively control the lateral (right-to-left) movement of the head carriage so as to align the arrow 5 opposite a
desired mode character or option, and key 11 operates to enter the selected mode or option in memory and thereby cause the printer to operate accordingly.
According to a preferred embodiment of the invention, upon entering a "mode-setting" mode, a listing of all available printing modes are printed on paper 2, each of such modes being identifiable by a different reference character, e.g. (1), (2), (3)...(n). Below the listing of printer modes, the corresponding reference characters are sequentially printed in the lateral direction on paper 2. The printhead carriage is then selectively moved laterally to a position in which arrow 5 is positioned opposite a reference character which identifies a mode of interest Upon selecting a mode of interest the various available options for the selected mode are sequentially printed out on paper 2 in a lateral direction. The printhead carriage is again selectively moved laterally to a position opposite a desired option, and the selected option is entered into memory. By virtue of displaying all printer modes and available options on the paper sheet and selecting a mode or option by controlling the lateral position of the print head, the DIP switches and liquid crystal displays of the prior art can be totally eliminated, as are the aforementioned disadvantages associated therewith.
FIG. 1 shows a control block diagram for the serial printer shown in FIG.2. Reference numeral 21 denotes a central processing unit (CPU) of a microcomputer MC which is operatively coupled to storage means 23, via a data bus 22. Storage means 23 comprises a read-only memory (ROM) 24 for storing a system program, a random-access memory (RAM) 25 for storing system data, and an electrically erasable programmable read-only memory (EEPROM) 26 which is a nonvolatile memory for storing data when power is off. A gate array 27 operates under the control of the CPU to control the movement of a carriage 4
(shown in FIG.2) which supports a printhead, such as an inkjet head or the thermal printing head of a dot-matrix printer.
CPU 21 outputs address signals to ROM 24, RAM 25 and gate array 27 through address bus 28 and also outputs call command signals or storage command signals. Gate array 27 outputs address signals to ROM 24 and RAM 25 through address bus 29 and also outputs call command signals or storage command signals. Storage means 23 stores various printer mode and mode options, which will be described later, in ROM 24 and also stores data representing the currently set modes in RAM 25 and EEPROM 26. Connected to CPU 21 is a driving circuit 31 which operates through a drive stepper motor 30 to move head carriage 4 in the lateral direction, i.e., perpendicular to the direction of paper movement CPU 21 is also operatively
connected to a driving circuit 33 which operates through a drive motor 32 to rotate platen roller 3. A position sensor 34 is arranged to detect the home position of head carriage 4, and a paper sensor 35 operates to detect whether or not the print- receiving member (paper 2) is in a printing position. The respective outputs of these senors, together with the outputs of key switches 7-11 provide inputs to the CPU.
CPU 21 further comprises position-deteπnining means 36, printing control means 37 and storage control means 38. Position-determining means 36 operates to determine the lateral position of the printhead carriage by counting the number of steps produced by stepping motor 30. The function of printing control means 37 is (a) to cause data representing the various printing modes and the currently set options, which are stored in RAM 25 or EEPROM 26 of storage means 23, to be printed on paper 2 by head carriage 4 when the "mode setting" has been commanded, as described below; (b) to cause certain different reference characters, preferably represented by alpha and/or numeric symbols and identifying the different possible printing mode selections stored in ROM 24, to be sequentially printed on paper 2 in the lateral direction thereof; and (c) to cause the different available options for a selected printing mode to be printed on paper 2 in the aforementioned lateral direction. When head carriage 4 is selectively moved (by means of key switches 8 and 9) to a position opposite a desired one of the reference characters or options printed on paper 2, storage control means 38 operates to cause the selected printing mode (represented by the selected character) and the selected printing mode option, both corresponding, at different times, to the lateral position of the moved head carriage 4 to be stored as the "set mode" in RAM 25 or EEPROM 26 of storage means 23.
The procedure for mode-setting is explained hereunder with reference to FIGS. 3-6'.. First the serial printer is switched to the "mode setting" mode or status by pushing power key switch 7 while holding down one of key switches 7-11. The present embodiment is so designed as to be switched to "mode setting" by pushing power key switch 7 while holding down key switch 8.
Upon entering the "mode-setting" mode, when paper 2 is fed to a predetermined printing initiation position (Step 1), data representing the printer's current mode settings (stored in EEPROM 26) are called out to RAM 25 and printed (Step2 ) on paper 2 by the CPU's printing control means 37. This step is represented by area a on paper 2 (shown in FIG. 3), where the reference characters (Item Nos. (1) through (11)) , the description of each printer mode and the mode
option currently set are printed in a sequence. A description of the function of the respective key switches 7-11 during the "mode setting" mode is printed immediately after the above process, as shown in area a' (Step 3).
Following the above, mode selection reference characters (1)...(11) are sequentially printed on paper 2 in the lateral direction thereof at specified intervals (Step 4: area b in FIG. 3). Head carriage 4 is automatically moved to the leftmost selection category (Exit) printed on paper 2 so that marker 5 of head carriage 4 is aligned with the said category (Step 5).
Then, the operator chooses a printer mode he wants to change and operates either one of key switches 8 and 9. With this operation, head carriage 4 moves to the category immediately to the left or right one item at a time, thereby enabling marker 5 of head carriage 4 to be aligned with the desired reference character (Steps 6 - 9). According to the present example, the paper size mode setting is the first selected. The operator positions marker 5 opposite reference character "(2)" and then operates selection key switch 11 (Step 10) to enter this selection.
When selection key switch 11 has thus been operated, the available options of the paper size mode stored in ROM 24 are sequentially printed on paper 2 in the lateral direction thereof at predetermined spaced positions by printing control means 37 of CPU 21. Head carriage 4 is then automatically moved to a position opposite the option category at which the printer mode is currently set with marker 5 pointing to this option (Step 12: area c in Fig.3).
Then, the operator chooses the desired paper size by operating key switches 8 or 9 to cause marker to move to a position opposite the desired option. Selection key switch 11 is then actuated to enter the selected option into memory, replacing the previously set option (Steps 13-17). In the example, the paper size has been changed from "US Letter" (which is printed out in bold type to accent the current option setting) to "A4".
When selection key switch 11 has thus been operated, the CPU 's position-determining means 36 determines the option to which the head carriage 4 has moved, and storage control means 38 stores data of the chtsen option in RAM 25 as the new setting for the paper size mode. Thereafter, the apparatus returns to Step 4, printing the mode selection reference characters and options laterally on paper 2 again (as shown in area b' and c'). In the case of resetting other modes immediately after the above process, the operator resets the mode in the same manner as above, by moving head carriage 4 so that marker 5 jrøints the category at which the mode in question to be set
When the mode setting has been completed, the operator positions marker 5 at "Exit" of the reference characters bar by means of moving head carriage 4. Upon exiting this program, the apparatus proceeds from Step 11 to Step 19, where information representing the "new" mode or printer-parameter settings is printed on paper 2 (Area d in FIG. 3).
Immediately thereafter, choices for saving the new modes, i.e. "Yes," "No" and "Change another," are sequentially printed on paper 2 in the lateral direction thereof at specified intervals (Step 20: area e in Fig. 3). Then, the operator makes his choice, positions marker 5 by moving head carriage 4, and operates selection key switch 11 (Steps 21-25). In case "Change another" has been selected (Step 26), the apparatus returns to Step 4 to repeat the mode setting process. If "Yes" has been selected, the data representing the newly set modes.which has been previously temporarily stored in RAM 25, is now stored in EEPROM 26 (Steps 27 and 28). If "No" has been selected, the mode setting is terminated with no further steps. In this case, the data of the newly selected options stored in RAM 25 are deleted. In other words, the printer is maintained in the condition of the previous mode setting.
As described above, mode setting is done by simply moving the head carriage to a position corresponding to a desired mode character or option printed on paper 2. Thus, mode setting is performed in a "user friendly" manner, with no need for operator manuals. Furthermore, as it requires neither conventional DIP switches nor liquid crystal displays, with software alone being sufficient it is possible to reduce parts cost and also make a printer compact Also, since mode selection data is printed on paper 2, it is possible to display a large quantity of data at once, compared with a device using a liquid crystal display. Consequently, mode setting is simplified.
This invention has been described in detail with particular reference to a preferred embodiment thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention.