JP4370175B2 - Display device control device and image forming apparatus having the same - Google Patents

Description

  The present invention relates to a display device control device, and more particularly to a control device capable of controlling the operation of a display device for displaying predetermined information to the outside.

  The present invention also relates to an image forming apparatus provided with such a display device control device.

  An image forming apparatus generally includes a control device configured by a microcomputer having a CPU, a RAM, a ROM, and the like, and an operation system (hereinafter referred to as an OS) stored in the ROM is called by the CPU into the RAM. An operating environment of various hardware such as an image forming unit is provided.

  On the other hand, the image forming apparatus has an input operation unit for performing printing instructions, setting printing conditions, and the like. The input operation unit normally displays a plurality of operation keys and input contents. And a panel.

  Some conventional image forming apparatuses have a display panel composed of a large liquid crystal display. In many cases, this type of apparatus is separate from a RAM for starting up an OS or the like in a control apparatus. The video RAM (hereinafter referred to as VRAM) used exclusively for controlling the display panel is employed, and the ROM has an operation program for controlling the normal operation of the display panel, and the entire apparatus is started up when the power is turned on. A display program for displaying a predetermined screen on the display panel is stored therein.

  In this type of control device, when the power is turned on, the CPU calls the OS stored in the ROM into the RAM and also calls the display program into the VRAM, so that the entire image forming apparatus is being activated for the user. To inform.

  In this type of apparatus, the CPU, VRAM, and ROM are connected to each other by a single bus. When the power is turned on, the CPU calls the OS RAM and calls the display program to the VRAM. Therefore, there is a problem that the bus is occupied by calling the OS and the display operation by the display program on the display panel is delayed.

Therefore, conventionally, a technique has been proposed in which priority is set for hardware such as a display panel that is desired to be quickly started up, and the entire apparatus is started up according to the priority (for example, Patent Document 1). reference).
Japanese Patent Laid-Open No. 8-292892

  However, in the above prior art, priority is given to the startup of the display panel, thereby delaying the start-up of the OS. As a result, communication with the CPU of other externally connected devices, reading of backup data stored in the ROM, etc. As a result, it takes a long time to start up the entire apparatus.

  An object of the present invention is to quickly start up an entire apparatus by reducing a processing load of a CPU while quickly performing a predetermined display operation on a display apparatus when an image forming apparatus or the like is activated. .

A control device according to claim 1 is a device capable of controlling an operation of a display device for displaying predetermined information to the outside, and includes a first storage unit, a first work area unit, a first processing unit, A second storage unit, a second processing unit, and a second work area unit are provided. The first storage unit stores an OS that can provide the operating environment of the display device and an operation program for normal operation of the display device. The first processing unit calls the OS to the first work area unit for a predetermined time after the power is turned on. The second storage unit stores a display program for displaying on the display device that the display device is being activated. The work area unit is connected to the first processing unit via the second processing unit, and can hold a display program called from the second storage unit. Then, the second processing unit calls the display program to the second work area unit for a predetermined time after the power is turned on. The first processing unit can call the operation program to the second work area unit after the call to the first work area unit of the OS is completed, and can execute the called operation program.

  In this apparatus, the second processing unit different from the first processing unit prepares the display program for the display device, thereby avoiding a delay in the display operation in the activated display device and the first processing unit. The processing load is reduced, and the OS is quickly prepared by the first processing unit. As a result, the start-up of the entire apparatus as the image forming apparatus or the like is accelerated.

  In the present invention, the case where the power is supplied includes not only the case where the power switch of the entire apparatus such as the image forming apparatus is turned on, but also the case where the entire apparatus is restarted by pressing a reset button or the like. It is. In addition, the work area unit may be any one that can hold at least a display program, and may further hold an OS.

  According to a second aspect of the present invention, there is provided the control device according to the first aspect, wherein the second storage unit and the second processing unit are included in one application-specific integrated circuit (hereinafter referred to as ASIC (Application Specific Integrated Circuit)). It is.

  Specifically, in this apparatus, a single ASIC having a second processing unit and a second storage unit is interposed between the first processing unit, the first storage unit, and the work area unit, thereby displaying the display device. The ASIC prepares the program to reduce the work load on the CPU, so that the OS can be quickly started up by the CPU.

According to a third aspect of the present invention, in the control device according to the first or second aspect, the display program is stored in a compressed state in the second storage unit, and is decompressed when called to the second work area unit. The

  In this apparatus, the processing burden on the second processing unit is reduced and the capacity burden on the second storage unit is reduced.

According to a fourth aspect of the present invention, in the control device according to any one of the first to third aspects, the second processing unit accesses the second work area unit until the OS preparation is completed. And after the OS preparation is completed, only the first processing unit can access the second work area unit.

  In this apparatus, when the first processing unit finishes the preparation of the OS, the access right to the work area unit is transferred from the second processing unit to the first processing unit, so that the OS can be quickly started up. I have to.

  An image forming apparatus according to a fifth aspect includes an input operation unit, a control device, and an image forming unit. The input operation unit includes a display device for displaying predetermined information to the outside and operation keys. The control device is a device according to any one of claims 1 to 4, capable of controlling an operation of the display device. The image forming unit can form an image based on the content input by the operation key.

  In this apparatus, the second processing unit prepares the display program for the display device, thereby reducing the processing load on the first processing device so that the OS can be quickly prepared by the first processing unit. Thus, the entire apparatus can be quickly started up.

  According to the present invention, by causing the second processing unit to prepare the display program for the display device, it is possible to avoid a delay in the display operation on the activated display device and to reduce the processing load on the first processing unit. This makes it possible to quickly prepare the OS by the first processing unit. Therefore, the start-up of the entire apparatus such as the image forming apparatus is accelerated.

[Image forming apparatus]
1 and 2 show an image forming apparatus 1 in which an embodiment of the present invention is adopted.

  The image forming apparatus 1 includes an input operation unit 3, an image forming unit 5, another input / output unit 7, and a control device 9.

  The input operation unit 3 includes a key group (operation keys) and a display panel (display device) not shown. The key group specifically includes a power key for turning on the power, a reset key for restarting the entire apparatus 1, a start key for instructing printing, and settings for setting various printing conditions. Has keys etc. The display panel is for displaying information related to printing, and here, a touch panel type liquid crystal display is employed.

  The image forming unit 5 is for performing image formation based on image information read by a document reading unit, which will be described later, and image data sent from an externally connected information processing apparatus. A photosensitive drum, a main charging device, a developing device, a transfer device, and a fixing device. The photosensitive drum has an electrostatic latent image formed on the surface. The main charging device is a device for charging the surface of the photosensitive drum. The developing device is a device that forms a toner image by supplying toner to the surface of the photosensitive drum on which the electrostatic latent image is formed. The transfer device is a device for transferring a toner image on the surface of the photosensitive drum onto a sheet. The fixing device is a device for fixing the transferred toner image on a sheet.

The other input / output unit 7 includes a document reading unit, a communication unit, a paper feed unit, and a paper discharge unit (not shown).
The document reading unit is for reading image information of a document fed onto the document table 12, and has an optical system (not shown). The communication unit is for transmitting and receiving information to and from an information processing apparatus connected to the outside via a LAN or the Internet. The paper feed unit is for transporting papers arranged in the plurality of paper feed cassettes 16 and the manual feed tray 14 toward the image forming unit 5. The paper discharge unit is for discharging the paper on which the image has been formed in the image forming unit 5 to the outside.

[Control device]
The control device 9 is a device for controlling the operation of the display panel and the like, and as shown in FIG. 3, a CPU (first processing unit) 11, a RAM 13, and a ROM (first storage unit) 15. And a microcomputer including an ASIC 17 and a VRAM (working area unit) 19.

  The CPU 11 controls the input operation unit 3, the image forming unit 5, and the like, and prepares the OS by calling the OS stored in the ROM 15 to the RAM 13 for a predetermined time after the power is turned on. When the preparation of the OS is completed, the CPU 11 calls the display panel operation program stored in the ROM 15 to the VRAM 19 via a bus 27 (described later) in the ASIC 17 and executes the called operation program.

  The RAM 13 functions as a work area for the CPU 11 and also holds image information read by the document reading unit.

  The ROM 15 stores control programs for the input operation unit 3, the image forming unit 5, and the other input / output unit 7. These control programs include an operation program for controlling the normal operation of the display panel. The ROM 15 stores an OS for providing an operating environment for these programs.

  As shown in FIG. 4, the ASIC 17 includes a processing unit (second processing unit) 21 configured by a logic circuit, a ROM (second storage unit) 23, a selector 25, and two buses 27 and 28. is doing.

  The processing unit 21 controls the display panel and the like, and prepares the display program by calling the display program stored in the ROM 23 into the VRAM 19 for a predetermined time after the power is turned on. The processing unit 21 has a function of adjusting the access right to the VRAM 19 between the CPU 11 and the ASIC 17. When the power is turned on, the ASIC 17 acquires the access right and the CPU 11 finishes the OS preparation. Until this is done, the CPU 11 is blocked from accessing via the bus 27 (see FIG. 5). When the preparation of the OS is completed, the access right is transferred to the CPU 11, and only the CPU 11 can access the VRAM thereafter (see FIG. 6).

  The ROM 23 stores a display panel display program. As the contents executed by the display program, specifically, a message indicating that the OS or the like is being prepared (for example, “please wait”) or a standby screen indicating that is displayed on the display panel. It is a program for. The display program is preferably stored in a compressed state in order to reduce the processing load on the processing unit 21 and the capacity load on the ROM 23, and is preferably configured to be decompressed when called to the VRAM 19.

  The selector 25 is for switching to any one of the access path buses 27 and 28 for the VRAM 19 and is disposed on the buses 27 and 28.

  The VRAM 19 is connected to the CPU 11 via the ASIC 17 and functions as a work area for the CPU 11 and the ASIC 17 and can hold a display program called from the ROM 23 of the ASIC 17.

[Operation of Image Forming Apparatus]
Next, the operation of the image forming apparatus 1 will be described based on FIG. 7 and FIG.

  In the image forming apparatus 1, as shown in FIG. 7, when the power key or the reset key is pressed and the power is turned on (S1), the ASIC 17 acquires the access right to the VRAM 19 (S2) and is stored in the ROM 23. The display program data is transferred to the VRAM 19 (S3). On the other hand, as shown in FIG. 8, in the CPU 11, as the power is turned on (S11), the OS data stored in the ROM 15 is transferred to the RAM 13 (S12).

  When the data transfer of the display program is completed in the ASIC 17 (S4), the display program called to the VRAM 19 is executed, and a message such as “Please wait for a while” is displayed on the display panel (S5). On the other hand, the CPU 11 waits for the OS data transfer to end (S6, S13), and the access right to the VRAM 19 is transferred to the CPU 11.

  The CPU 11 having acquired the right to access the VRAM 19 in this way (S14) transfers the operation program data of the display panel stored in the ROM 15 to the VRAM 19 via the bus 27 (S15), and when the data transfer is completed (S15). (S16) The operation program is executed to control the operation of the display panel so that normal screen display is performed (S17).

  According to the image forming apparatus 1 as described above, by preparing the display program for the display panel in the ASIC 17 instead of the CPU 11, the processing load on the CPU 11 can be reduced and the OS can be concentrated on starting up. The OS can be started up early, and as a result, the entire apparatus 1 can be started up quickly.

  On the other hand, until the OS has been started up, a predetermined message is displayed on the display panel by the ASIC 17 so that the display delay can be eliminated and the user can be prevented from feeling uncomfortable.

[Other Embodiments]
(A) In the above embodiment, the OS may be started up and the display program may be executed by one RAM connected to the CPU 11 via the ASIC instead of the VRAM and RAM. In this case, access from the CPU 11 and access from the ASIC compete for the RAM, but it is possible to perform access arbitration by the ASIC.

  Specifically, the ASIC blocks the CPU 11 from accessing the RAM until the display program preparation is completed, and transfers the access right to the RAM to the CPU after the display program preparation is completed. To arbitrate the access right.

  More specifically, when power is turned on in the ASIC 17, the bus 28 is selected, and the ASIC 17 acquires the access right to the VRAM 19. When the preparation of the display program in the VRAM 19 is completed, the processing unit 21 sets a bit indicating that the preparation of the display program is completed in the selector 25, and the CPU 11 periodically accesses the selector 25 to recognize this bit. Thus, the selector 25 is switched and the bus 27 is selected, whereby the access right to the VRAM 19 is transferred from the ASIC 17 to the CPU 11.

  (B) In the case of (a) above, the processing unit 21 of the ASIC 17 causes the CPU 11 or the CPU 11 if the selector 25 is not switched even after a predetermined time elapses by a timer that operates after the bit is set in the selector 25. It is determined that an abnormality has occurred in other parts of the image forming apparatus 1 (for example, the CPU 11 is out of control), a bit indicating that an abnormality has occurred is set, and an abnormality has occurred in the display panel. An error message for notification may be displayed.

  (C) In the above embodiment, the configuration and operation of the ASIC are not limited to those described above and illustrated in FIG.

  (D) The present invention can be applied to other devices including a display device in addition to the image forming apparatus.

1 is a perspective view showing an image forming apparatus in which an embodiment of the present invention is adopted. FIG. 2 is a block diagram illustrating a configuration of the image forming apparatus. FIG. 2 is a block diagram illustrating a configuration of a control device of the image forming apparatus. The block diagram which shows the structure of ASIC of the said control apparatus, and its periphery. The block diagram which shows operation | movement of the said control apparatus. The block diagram which shows operation | movement of the said control apparatus. The flowchart for demonstrating operation | movement of the process part 21 of the said control apparatus. The flowchart for demonstrating operation | movement of CPU11 of the said control apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 3 Input operation part 5 Image forming part 9 Control apparatus 11 CPU (1st process part)
15 ROM (first storage)
17 ASIC
19 VRAM (work area)
21 ASIC processing unit (second processing unit)
23 ASIC ROM (second storage)

Claims (5)

A control device capable of controlling the operation of a display device for displaying predetermined information to the outside,
An operating system capable of providing an operating environment of the display device; a first storage unit storing an operation program for normal operation of the display device;
A first work area section;
A first processing unit that calls the operating system into the first work area unit for a predetermined time after power-on;
A second storage unit storing a display program for displaying on the display device that the display device is being activated;
A second processing unit;
A second work area unit connected to the first processing unit via the second processing unit and capable of holding a display program called from the second storage unit;
The second processing unit calls the display program to the second work area unit for a predetermined time after power-on,
The first processing unit can call the operation program to the second work area unit and execute the called operation program after the call to the first work area unit of the operating system is completed. ,
Control device for display device. The second storage unit and the second processing unit are included in one application-specific integrated circuit.
The control apparatus for display apparatuses as described in any one of Claims 1-3. The display device control device according to claim 1, wherein the display program is stored in a compressed state in the second storage unit, and is decompressed when the display program is called to the second work area unit. . The second processing unit waits until the preparation of the operating system is completed.
Blocks the processing unit from accessing the second work area unit and allows only the first processing unit to access the second work area unit after the operating system is ready. ,
The control apparatus for display apparatuses in any one of Claim 1 to 3. An input operation unit including a display device and operation keys for displaying predetermined information externally;
The control device according to any one of claims 1 to 4, capable of controlling an operation of the display device;
An image forming unit capable of forming an image based on contents input by the operation keys;
An image forming apparatus.

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