JPH0412865A - Image processor - Google Patents

Abstract

PURPOSE:To selectively combine an image processor with a plurality of image forming apparatuses by selecting an image starting position information table within a memory dry the kind of the discriminated image forming apparatus, and controlling the image starting position by the count in an image clock counting means. CONSTITUTION:There are provided an image clock counting means 12 for counting image clocks from the time when a line synchronous signal generated by an image forming apparatus 10 is input to the time when the image starting position is reached, a discriminating means 13 for discriminating the kind of an image forming apparatus 2, a memory 14 which stores an image starting position information table for every kind of the image forming apparatuses, and an image starting position controlling means 15 for selecting the image starting position information table in the memory 14 according to the kind of the image forming apparatus 10 discriminated by the discriminating means 13, and controlling the image starting position by the count in the image clock counting means 12.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an image processing device in a printing device such as a page printer such as a laser printer, a facsimile machine, or a digital copying machine.

[Conventional technology]

A printing device such as a laser printer consists of an image processing device that receives character information or image information from a host system and generates image information, and a printer that receives the image information from the image processing device and performs line scanning to record it. It consists of an image forming device that forms an image on a medium.

Conventionally, the image forming apparatus and the image processing apparatus have been constructed under the concept of being integrated, and the image processing apparatus has created an image based on information specific to the image forming apparatus.

[Problem that the invention seeks to solve]

However, the characteristics of such a printing device consist of both the characteristics of the image processing device and the characteristics of the image forming device, and a combination of the two should make it possible to create a printing device with different characteristics.

However, the image starting position in particular affects the mechanism of the image forming apparatus, and each position has its own unique value.

Therefore, in conventional printing apparatuses, the above-mentioned combinations were not possible.

The present invention has been made with attention to such problems, and an object of the present invention is to enable selective combination of a plurality of image forming apparatuses with one image processing apparatus.

[Means to solve the problem]

In order to achieve the above object, the present invention provides an image processing device 11 that supplies image information to an image forming device 10 that performs line scanning to form an image on a recording medium, as shown in a functional block diagram in FIG. , an image clock counting means 12 for counting the image clock from the input point of the line synchronization signal generated by the image forming apparatus 10 to the image start position, and an identifying means 1 for identifying the type of the image forming apparatus 2.
3, a memory 14 that stores an image start position information table for each type of image forming apparatus, and an image start position information table in the memory 14 that is selected according to the type of image forming apparatus 10 identified by the identifying means 13, Image start position control means 15 for controlling the image start position based on the count value by clock count means 12 is provided.

Alternatively, the identification means 13 and the memory 1 in FIG.
4 may be omitted and the image start position information may be obtained directly from the image start position control means 15 or the image forming apparatus 10.

[For production]

According to the image processing apparatus of the present invention configured as described above,
Since the image starting position of an image forming device can be controlled according to the type of image forming device, it is possible to control multiple image forming devices registered for one image processing device or to connect an arbitrary image forming device. combinations are possible.

〔Example〕

Hereinafter, an embodiment in which the present invention is applied to a laser printer will be described based on FIG. 2 and subsequent figures of the accompanying drawings.

In the following explanation, the image forming apparatus will be referred to as an "engine".
The image processing device is called a "controller."

FIG. 2 is a block diagram showing a schematic configuration of the laser printer system, which includes a host system 1,
A printer main body 4, which is an image forming apparatus main body consisting of a controller 2 and an engine 3, and a host interface (hereinafter abbreviated as "host I/F J") that connects them.
5 and a laser printer video interface (hereinafter abbreviated as rLPVIJ) 6.

The host system 1 is an information processing device such as a word processor, an office computer, or a personal computer that sends text information or image information.

The controller 2 is an image processing device that receives text information and image information from the host system 1 and generates image information (video data) for each page of print paper.

The engine 3 is an image forming device that prints image information generated by the controller 2 onto paper.

Host I/F 5 connects host system 1 and controller 2
It is an interface for connecting between R5232 and
C, Centronics I/F, etc. are well known.

LPVI6 is a standard interface that connects the controller 2 and engine 3 that make up the printer body 4. It unifies the video interface hardware, which was previously determined individually for each engine (each model), and makes it possible to integrate the functions of the engine. It is designed so that it does not change from side to side.

FIG. 3 shows the hardware configuration of the controller 2.

This controller 2 includes a CPU 20, a program ROM 21. RAM22. Font ROM2”S
, non-volatile RAM24. Operation panel 25. Magnification processing section 2
6. Optional interface 27. Video control unit 28
．． It consists of an engine interface 29, and controller side portions of the aforementioned host interface 5 and LPVI 6, each of which is connected by a CPU bus.

The CPU 20 is a central processing unit that centrally controls the entire controller 2, and is a general-purpose 16-bit or 32-bit
Uses a BIT microcomputer.

The program ROM 21 stores microcode (program) for controlling the CPU 20.

RAM22 is a large capacity random access memory,
It is mainly used for the following purposes.

(a) System memory (b) Input buffer (c) Page buffer (d) Font file (e) Macro file (f) Image file (g) Print control file (h) Video buffer Figure 4 shows the data processing The relationship between the flow and each buffer and file in this RAM 22 is shown.

Information sent from the host system 1 is stored in the input buffer 22b via the host interface 5.

The data stored in this input buffer 22b is
are processed by the data processing unit 201, and depending on the type of data, a page buffer 22c, a font file 22d, a macro file 22e, an image file 22f, a print control file 22g,
be registered in either.

That is, print sequence control data (paper transport path designation, print number designation area) is stored in the print control file 22g, page layout information (relationship between print data and print position, etc.) is stored in the page buffer 22C,
Image information is registered in the image file 22f, downloaded fonts are registered in the font file 22d, overlay information, etc. are registered in the macro file 22e.

The image information processing unit 202 generates the image file 22f according to the contents of the page buffer 22c.

The contents of the font file 22d and font ROM 23 are expanded into the video buffer 22h through the scaling processing section 26.

When the printing data for one page is completed in the video buffer 22h, the print control unit 203 starts the engine 3 via LPVI according to the contents of the print control file 22g, and when the engine 3 reaches the image recording timing, the video buffer 22h sends the expanded video data to the engine 3 via the LPV module 6.

Engine 3 prints the video data sent through LPVI onto paper.

Returning to FIG. 3, the font ROM 2''S stores font data for converting character information sent from the host system 1 via the host interface 5 into image information.

The nonvolatile RAM 24 is a memory that stores information for controlling the operating state of the printer after the power is turned on, and mainly stores the following items.

(a) Print direction (b) @type (font) (C) Character size (cl) Line spacing (e) Paper feed 0 (f) Paper ejection slot (g) Host interface The storage contents of this non-volatile RAM 24 can be Panel 25
Updated from.

The host interface 5 is an interface that connects the host system 1 and the controller 2, and is provided with two types: Centronics-compliant parallel and R5-232C, and is selected by operating the operation panel 25 described above.

The option interface 27 is an interface for externally supplying fonts and programs to expand functionality, and in this example can handle two IC carts 7.

The IC card 7 is a commercially available card, and depending on the type of data stored, there are cards that store a font card, a program card, or both, but they are physically the same card.

The video control unit 28 converts the video data stored in the video buffer 22h in FIG. and sends it to engine 3.

The engine interface 2 has a serial communication (transmission/reception) function that detects the engine status using bidirectional serial signals via the LPVI 5 and controls the engine by sending commands.

Here, the signal of LPVI6 is shown in FIG. Each signal consists of an image signal system, a control signal system, and a power supply.

The image signal system is /WCLK, /WDATA, /LSYN
There are four types of signals: C1/FGATE.

The control signal system is /PETXD, /PERXD, /PEC
There are four types of signals: TS and /PEDTR, and the power supply is:
There are two types: +5V and GND.

Here, the "/" prefixed to each signal name indicates negative logic (low active), and is shown with an overline in FIG. 5.

(a) /WCLK, image clock for synchronizing image data from the print engine.

Synchronize with the falling edge of this signal and image data (/WDAT A) Print the image. low level black.

(b) /WDATA, image data sent from the video control unit 28 in FIG.

(c) /LSYNC: Line synchronization signal indicating the start of each scan line.

/WCLK signal falling Sync.

(d) /FGATE: A signal indicating the effective image area in the paper feeding direction. / Synchronized with the falling edge of the LSYNC signal.

(e) /PETXD: Status signal for informing the engine status from the engine to the controller.

(f) /PERXD: Command line from controller to engine.

(g) /PECTS: Indicates the ready of /PETXD signal. When this signal is at a low level, it becomes possible for the engine to send status information to the controller.

(h) /PEDTR: Indicates the ready of /PERXD signal. When this signal is at a low level, the controller can send commands to the engine.

(i) +5V: + supplied from the engine
5■ Power supply.

(j) GND Nigeland (Earth) Here, the timing of the image signal when the paper size is letter size is shown in FIG. Further, the relationship with the image effective area in that case is shown in FIG.

For the line synchronization signal r-s YNC of each line, there is an offset shown as LOFF in FIG. 7 before the image becomes valid.

This is determined by the relationship between the scan area of the laser beam and the position where the paper passes, and the value of LOFF is an engine-specific value that indicates the image start position.

The video control unit 28 in FIG. 3 includes a counter for counting this LOFF and a counter for counting the image effective width, and necessary values are set by the CPU 20 before executing the printing operation.

The video control unit 28 uses the image clock WCLK for each line based on the line synchronization signal LSYNC of the image signal.
is counted by the above counter, and the image data of the specified width is output to the specified position.

Information about the image start position LOFF and the effective image width (paper width) is stored as a table in the program ROM 21 shown in FIG.

This table shows L for each paper size as shown in Figure 8.
It takes an array structure with OI-F and image effective width information.

Previously, controllers only had one table, so they could only connect to a specific engine.

In this embodiment, this table is provided for the number of engines assumed, and the CPU 20 identifies the type of engine using communication means between the controller and the engine, and selects the table to be used from among the plurality of tables. This allows for selective combination of multiple engines in one controller.

An ID number is assigned to the carrot in advance as an identification means.

After turning on the power, the controller inquires of the engine ID number by command to the engine, determines the above-mentioned table to be used during printing, and uses it thereafter.

Therefore, in this embodiment, the CPU 20 uses the identifying means 13. of FIG. The program ROM 21 is a memory 14 storing an image start position information table, and the video control unit 28 is an image clock counting means 12 and an image start position control means 1.
It corresponds to 5.

Here, communication between the controller and the engine will be briefly explained.

The communication conditions between the controller and the engine are as follows.

1, Interface: Asynchronous serial I/F 2, Communication speed: 9600 baud 3, Parity bit: None 4, Stop bit: 1 As mentioned above, communication between the controller and engine is LP
4 types of signals /PETXD, /PERX via VI
D, /PECTS, and /PEDTR.

The signals for these interfaces were briefly explained above, but will now be explained in more detail.

(1) /PERXD This signal is a serial communication receive data signal line for sending commands from the controller to the engine.

(2) /PETXD This signal is a serial communication transmission data signal line that sends responses and event reports from the engine to the controller.

(3) /PEDTR This signal is a serial communication ready signal line for command transmission. When this signal is -L=, it indicates that the controller may send commands to the engine.

Except for power-on or initialization operations (including establishing system configuration), the engine
This signal must be held at °L''.

(4) /PECTS This signal is a serial communication ready signal line for transmitting a response or an event report.

When this signal is "°L", it indicates that the engine may send a response or event report to the controller.

The controller must hold this signal "L" except when the power is turned on or when it is unable to communicate with the engine.

If the engine receives too many event reports while this signal is high, it may discard old event reports.

Next, the communication protocol between the controller and the engine will be briefly explained.

Communication between the controller and the engine is performed by sending commands from the controller to the engine, and the engine receiving the commands and sending responses back to the controller.

Each command consists of a 1-byte argument and an operator, and as shown in Figure 9 (aL(b)),
The most significant bit of the argument is always °1° and the most significant bit of the operator is always O.

Commands send arguments first and operators later.

The argument can be omitted, and the engine must still interpret the command without that argument correctly.

If a command consisting of an argument and an operator (for example, a ``status request'' command) is issued by the controller without an argument,
Previous arguments to the same command effectively take effect.

When the engine receives a command, if there are no valid arguments, the engine takes the default value as the de facto argument.

The response sends the information requested by the received command from the engine to the controller.

The length of each response is 1 byte, and its most significant bit is 0° as shown in FIG. 9(c).

However, in the case of a response to the "illegal command" shown in FIG. 2(d), all bits are 1.

The event report is for sending unrequested information from the engine to the controller as a response when an event (jam occurrence, supply shortage, etc.) occurs in the option unit or engine.

Each event report has a length of 1 byte, as shown in FIG. 9(e), and its most significant bit is 1~.

Next, other embodiments of the invention will be described.

Image start position information (L○FF) mentioned above by the controller
Instead of owning a table of image effective width and image width, each engine owns this table as a unique value.

The controller uses commands for each printing operation to obtain this information from the engine and sets it in the video control section.

In this way, it becomes possible to combine one image processing device with any image forming device.

Although the embodiments described above are examples in which the present invention is applied to a laser printer, the present invention can be similarly applied to various printing devices such as other page printers, facsimile machines, and digital copying machines.

〔Effect of the invention〕

As described above, the image processing apparatus according to the present invention can control the image start position of the image forming apparatus according to the type of image forming apparatus, so that the image processing apparatus according to the present invention can be registered with respect to one image processing apparatus. This makes it possible to combine multiple image forming apparatuses or arbitrary image forming apparatuses.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the functional configuration of an image processing apparatus according to the present invention together with an image forming apparatus, FIG. 2 is a block diagram showing the configuration of a laser printer system which is an embodiment of the present invention, and FIG. A block diagram showing the configuration of the controller 2, FIG. 4 is an explanatory diagram showing the flow of data processing in the embodiment shown in FIG. 2, and the relationship between each file and file in the RAM 22 shown in FIG. An explanatory diagram showing each signal of the LPVI, FIG. 6 is a timing chart showing the timing of the image signal when the paper size is letter size, and FIG. 7 is an explanatory diagram showing the relationship with the image effective area in that case. FIG. 8 is an explanatory diagram showing an example of an information table of image starting position ILOFF and image effective width. FIG. 9 is an explanatory diagram of commands and responses used between the controller 2 and the engine B. Host system 2 Controller (image processing device) 3 Engine (image forming device) 10 Image forming device 11 Image processing device 12...
Image clock counter 13...Identification means 14...Memory 15 storing image start position information table...Image start position control means Fig. 5 Fig. 7 Fig. ○ b7 b6 b5 b4 b3 b2 b7
b6 b5 b4 b3 b2b7 b6
b5 b4 b3 b2 b7 b6 b5
b4 b3 b2-45 Figure 8

Claims (1)

[Scope of Claim] In an image processing device that supplies image information to an image forming device that performs line scanning to form an image on a recording medium, the image processing device provides an image processing device that performs line scanning to form an image on a recording medium from the time of input of a line synchronization signal generated by the image forming device. an image clock counting means for counting image clocks up to a start position; an identification means for identifying the type of the image forming apparatus; a memory storing an image start position information table for each type of image forming apparatus; image start position control means for selecting an image start position information table in the memory according to the type of the identified image forming apparatus and controlling the image start position according to the count value by the image clock counting means; An image processing device characterized by: 2. In an image processing device that supplies image information to an image forming device that performs line scanning to form an image on a recording medium, an image clock from the input point of a line synchronization signal generated by the image forming device to the image start position. image clock counting means for counting, and image starting position control means for obtaining information on the image starting position from the image forming apparatus and controlling the image starting position based on the count value by the image clock counting means. An image processing device characterized by: