JPH08149276A - Image forming system - Google Patents

Abstract

(57) [Summary] [Object] An object of the present invention is to provide an image forming system that does not cause a memory shortage by changing the macro capacity registered in the image forming apparatus according to the condition of a display list to be created. A host computer having information expansion means for expanding one page of characters, graphics, bitmap images and image information having drawing position information into a display list for each band, and a communication means for communicating with the image forming apparatus 17. An image forming device 17 having an image expanding means 18 for expanding page data for forming an image from a display list for one page, an image forming means 19 for printing an image on a sheet, and a communication means for communicating with a host computer. did.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming system used as an output terminal of various electronic devices.

[0002]

2. Description of the Related Art Conventionally, various image forming apparatuses have been proposed as output terminals for personal computers and workstations. The conventional image forming apparatus will be described below.

FIG. 11 is a block diagram of a conventional image forming apparatus. The data transferred from the host computer to the information expanding means 7 via the cable 1 is once stored in the memory A2 which is a receiving buffer to form an intermediate image. The intermediate image referred to here is "a", "b", "c".
Each character such as, etc., each graphic such as straight line, circle, etc., where each image exists in one page, information such as actual character, storage address of bitmap image such as image etc. What you have, is commonly called a display list. Further, a means for dividing one page into several pieces and storing the image information for one division is called a hand buffer. In the following, a description will be given of a configuration in which, in the band buffer method with eight bands, page data to be actually image-formed is developed for three bands and then data is started to be transferred to the image forming means 16. The information expanding means 7 is a memory A2 which is a receiving buffer and a memory B which stores a display list.
3. Memory C5 which is a buffer for creating page data
And CPU4.

Conventionally, when performing image forming processing in a band buffer type image forming apparatus, the data transferred from the host computer to the information expanding means 7 via the cable 1 is once stored in the memory A2 which is a receiving buffer. It At this time, in order to transfer data at high speed, when repeatedly transferring the same data, the data to be repeatedly transferred is registered in the image forming apparatus. This data is called macro. When transferring this data, the data can be transferred at high speed by transmitting only the macro number.

A display list for each band is created in the memory B3 based on the data stored in the memory A2. Regardless of the state of the page to be image-formed, the page data to be actually image-formed for 3 bands is expanded from the display list in the memory B3 to the page expansion memory C5. When the development is completed, an image forming signal is input to the image forming means 16 via the cable 6 and it is confirmed whether the image forming apparatus is in the image formable state. At the same time, page data for actually forming an image from the display list to the fourth band is started to be created in the memory B3. When the image can be formed, the image forming means 16 turns on the motors of the photoconductor 10, the LSU 8 and the like to prepare for laser emission and the like. Next, it is checked whether the vertical synchronizing signal for starting printing is output to the information expanding means 7. When the vertical synchronizing signal is turned on, the information expanding means 7 takes out page data from the memory C5 and sends it to the image forming means 16. The image forming means 16 supplies a laser beam having a laser power corresponding to the transferred data to the LSU.
A latent image is formed by irradiating the photosensitive member 10 from 8 to expose it. Next, in the developing device 11, development is performed to visualize the latent image, a visible image is generated on the photoconductor 10, and the paper 13 is placed at the timing when the visible image is placed on the paper.
Feed from 2. Next, the image is fixed on the paper by the fixing device 15, and it is checked whether or not the paper 13 is ejected, and each motor is turned off to finish the printing.

[0006]

In such a conventional image forming apparatus, when the macro capacity is large, there is a problem that printing is impossible due to a shortage of memory during the preparation of the display list.

The present invention has been made in order to solve the above-mentioned conventional problems, and by changing the macro capacity registered in the image forming apparatus according to the condition of the display list to be created, the memory shortage does not occur. An object is to provide an image forming system.

Further, among the macros registered in the image forming apparatus, a macro storing means for receiving and storing a macro unnecessary for printing from the image forming apparatus, and a macro among the macros registered in the image forming apparatus are printed. An object of the present invention is to provide an image forming system that reduces an unnecessary macro capacity of an image forming apparatus by a macro reducing unit that extracts an unnecessary macro.

Further, all the macros registered in the image forming apparatus are stored in the host computer, and only the macros used for printing are transmitted to the image forming apparatus, and only the macros necessary for printing are stored in the host computer. It is an object of the present invention to provide an image forming system having only the macro capacity necessary for the image forming apparatus by the macro reducing unit received from the image forming apparatus.

[0010]

To this end, the present invention provides
Information expanding means for expanding image information having pages of characters, graphics, bitmap images and drawing position information into a display list for each band, a host computer having communication means with the image forming apparatus, and a display for one page An image forming system is constituted by an image forming unit having an image expanding unit for expanding page data for forming an image from a list, an image forming unit for printing an image on a sheet, and a communication unit for communicating with a host computer.

[0011]

With the above arrangement, the information developing means of the host computer and the image developing means of the image forming apparatus
You can print without running out of memory.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram of an image forming apparatus according to a first embodiment of the present invention. The image forming apparatus 17 includes an image developing unit 18 and an image forming unit 30.
The image expanding unit 18 is composed of an image creating unit 19 and a CPU-A 21 which is a macro deleting unit 20. Further, the image creating means 19 uses the memory A as a reception buffer.
22 and a memory B23 for storing a display list, and the macro deleting means 20 has a memory C24 for storing a free memory capacity, a memory D25 for storing a macro,
It is composed of a memory E26 for storing macro numbers to be reduced and a memory F27 for storing page data.

FIG. 2 is a block diagram of a host computer according to the first embodiment of the present invention. The information expanding means 32 of the host computer 31 is composed of an information creating means 33, a macro saving means 34 and a CPU-B 35. Further, the information creating means 33 is composed of a memory G36 for storing data to be transmitted to the image forming apparatus 17 and a memory H37 for storing a display list, and the macro storage means 34 is a memory I3 for storing the capacity of the display list.
8, a memory J39 for storing the free memory capacity of the image forming apparatus 17, a memory K40 for storing macros, a memory L41 for storing the numbers of macros to be reduced, and a memory M42 for storing the numbers of macros to be used. .

Further, the host computer 31 and the image forming apparatus 17 are connected to the cable 28 and have a communication function in which the communication speed of the display list for one band is faster than the developing speed of one band in the image forming apparatus 17.

3 and 4 are flowcharts of the operation of the image forming apparatus of the first embodiment of the present invention, and FIG. 5 is a flowchart of the operation of the host computer. In FIG.
First, an inquiry signal of the free memory capacity, the registered macro number and the macro contents is received from the host computer 31 (step 1-1). The free memory capacity is retrieved from the memory C24 and the registered macro number and macro contents are retrieved from the memory D25 and transmitted to the host computer 31 (step 1-2). Next, in the image forming apparatus 17, the host computer 31 compares the display list capacity of the data to be printed with the free memory capacity received from the image forming apparatus 17, and the display list capacity is received from the image forming apparatus 17. When it is larger than the free memory capacity, the host computer 31 waits for a memory error signal to be transmitted (step 1-
3). When a signal other than the memory error signal is received,
Go to step 1-10.

Next, the memory capacity (display list capacity-free memory capacity) which is insufficient for printing by the image forming apparatus 17 is received from the host computer 31 (step 1-4). Further, the macro number used for the data to be printed is received from the host computer 31 (step 1-5). The image forming apparatus 17 determines one macro number to be reduced from the registered macros other than the macro number used for the data to be printed, and stores it in the memory E26.
(Step 1-6). The capacity of the macro contents corresponding to the macro number to be reduced is calculated from the memory D25,
The insufficient memory capacity is compared with the reduced memory capacity (step 1-7), and steps 1-6 are repeated until the reduced memory capacity becomes larger than the insufficient memory capacity.

The macro number to be reduced is fetched from the memory E26 and transmitted to the host computer 31 (step 1
-8), The macro content corresponding to the transmitted macro number is deleted from the memory D25, and the free memory capacity is expanded (step 1-9).

Next, the display list is received from the host computer 31, stored in the memory B23 (step 1-10), and the page data for actually forming an image for three bands is expanded from the display list in the memory B23, The data is stored in the memory F27 (step 1-11). Upon completion of receiving and expanding the display list from the host computer 31, an image forming signal is input to the image forming means 30 via the cable 29 (step 1-1).
2) It is confirmed whether the image forming apparatus 17 is in a printable state (step 1-13). If printing is possible, it is checked whether a vertical synchronizing signal for starting printing has been output to the image developing means 18 (step 1-14).

When the vertical synchronizing signal is turned on, the image developing means 18 takes out page data from the memory F27 and sends it to the image forming means 30 (step 1-15). At the same time, page data is expanded to the next band (step 1-16),
In the developing device, development is performed to visualize the latent image, and a visible image is generated on the photoconductor. Next, the sheet is fed from the cassette at the timing when the visible image is placed on the sheet, and the image is fixed on the sheet by the fixing device. Next, it is checked whether or not the paper has been discharged. If the paper has been discharged, the image forming means 30 turns off each motor and finishes printing (step 1-17).
When printing is completed, a print end signal is transmitted to the host computer 31 (step 1-18), the reduced macro number and the macro contents are received from the host computer 31,
The data is stored in the memory D25 (step 1-19).

Corresponding to the image forming apparatus 17, the host computer 31 transmits to the image forming apparatus 17 an inquiry signal for the free memory capacity, the registered macro number and macro contents (step 2-1). The free memory capacity and the registered macro number and macro content are received from the image forming apparatus 17, and the free memory capacity is stored in the memory J39 and the macro number and macro content are stored in the memory K40 (step 2-
2). The host computer 31 creates a display list from the image data and stores it in the memory H37 (step 2-3). Next, the display list capacity is calculated from the display list stored in the memory H37,
The macro number used in the print page is extracted while being stored in the memory I38 and stored in the memory M42 (step 2-4). The host computer 31 compares the display list capacity of the data to be printed with the free memory capacity received from the image forming apparatus 17 (step 2-5),
If the free memory capacity received from the image forming apparatus 17 is larger than the display list capacity, the process proceeds to step 2-10.

When the free memory capacity received from the image forming apparatus 17 is larger than the display list capacity, a memory error signal is transmitted (step 2-6). The memory capacity (display list capacity-free memory capacity) that is insufficient for printing by the image forming apparatus 17 is determined by the image forming apparatus 17
(Step 2-7). Next, from the memory M42, the macro number used in the print page is input to the image forming apparatus 17
(Step 2-8). The image forming apparatus 17 receives the macro number to be reduced, which is determined based on the macro number used for the print page, and stores it in the memory L41 (step 2-9). Next, the memory H3 is sent to the image forming apparatus 17.
The display list stored in 7 is transmitted (step 2-10). A print end signal indicating the end of printing is received from the image forming apparatus 17 (step 2-11), and the macro number and macro content reduced by the image forming apparatus 17 are transmitted from the memory L41 (step 2-12).

FIG. 6 is a block diagram of an image forming apparatus according to the second embodiment of the present invention. The image forming apparatus 43 is composed of an image developing unit 44 and an image forming unit 55. The image developing means 44 is composed of an image creating means 45, a macro deleting means 46 and a CPU-C 47. Further, the image creating means 45 comprises a memory N48 as a receiving buffer and a memory O49 for storing a display list, and the macro deleting means 46 stores a memory P50 for storing a free memory capacity, a memory Q51 for storing a macro, and page data. It is composed of a memory R52 for storing.

FIG. 7 is a block diagram of a host computer according to the second embodiment of the present invention. The information expanding means 57 is composed of an information creating means 58, a macro saving means 59 and a CPU-D 60. Further, the information creating unit 58 stores the data to be transmitted to the image forming apparatus 43 in the memory S61,
The macro storage unit 59 includes a memory T62 for storing a display list, a memory U63 for storing a display list capacity, a memory V64 for storing a free memory capacity of the image forming apparatus 43, and a memory W65 for storing a macro. Memory X6 for storing macro numbers
6 is comprised.

Further, the host computer 56 and the image forming apparatus 43 are connected to the cable 53 and have a communication function in which the communication speed of the display list for one band is faster than the developing speed for one band in the image forming apparatus 43. .

8 and 9 are flowcharts of the operation of the image forming apparatus according to the second embodiment of the present invention, and FIG. 10 is a flowchart of the operation of the host computer. In FIG. 8, first, an inquiry signal of the registered macro number and macro contents is received from the host computer 56 (step 3-1). All registered macro numbers and macro contents are fetched from the memory Q51 and sent to the host computer 56 (step 3-2). Next, the image forming apparatus 43 deletes all the registered macros and stores the freed memory in the memory P50 in addition to the free memory capacity (step 3-3). The free memory capacity is taken out from the memory P50 and transmitted to the host computer 56 (step 3-4). The macro number and macro contents used for the data to be printed are received from the host computer 31 and stored in the memory Q51 (step 3-5). Next, the display list is received from the host computer 56, stored in the memory O49 (step 3-6), the page data for actually forming an image for three bands is expanded from the display list in the memory O49, and is stored in the memory R52. Store (step 3-7). Upon completion of receiving and expanding the display list from the host computer 56, an image forming signal is input to the image forming means 55 via the cable D54 (step 3-8).
It is confirmed whether the image forming apparatus 43 is in a printable state (step 3-9). If printing is possible, it is checked whether the vertical synchronizing signal for starting printing has been output to the image developing means 44 (step 3-10). When the vertical synchronizing signal is turned on, the image developing means 44 takes out page data from the memory R52 and sends it to the image forming means 55 (step 3-1).
1). At the same time, page data is expanded to the next band (step 3-12), and development is performed in the developing device to visualize the latent image, and a visible image is generated on the photoconductor. next,
The sheet is fed from the cassette at the timing when the visible image is placed on the sheet, and the image is fixed on the sheet by the fixing device. next,
It is checked whether or not the paper has been discharged. If the paper has been discharged, the image forming means 55 turns off each motor and finishes the printing (step 3-13). When printing is completed, a print end signal is transmitted to the host computer 56 (step 3-1).
4), delete all macros stored in the memory Q51 (step 3-15).

The host computer 56 corresponding to the image forming apparatus 43 transmits an inquiry signal of the macro number and macro contents registered in the image forming apparatus 43 (step 4-1). The registered macro number and macro content are received from the image forming apparatus 43, and the macro number and macro content are stored in the memory W65 (step 4-2). The host computer 56 transmits an inquiry signal for the free memory capacity to the image forming apparatus 43 (step 4-3). The free memory capacity is received from the image forming apparatus 43, and the memory V
The data is stored in 64 (step 4-4). A display list is created from the image data and stored in the memory T62 (step 4-5). Next, the display list capacity is calculated from the display list stored in the memory T62, stored in the memory U63, and the macro number used in the print page is extracted and stored in the memory X66 (step 4-6). The host computer 56 extracts from the memory X66 the macro number and macro content used for the page to be printed, and sends it to the image forming apparatus 43 (step 4-7). Next, the memory T62 is sent to the image forming apparatus 43.
The display list stored in is transmitted (step 4-8). A print end signal indicating the end of printing is received from the image forming apparatus 43 (step 4-9).

[0027]

As described above, according to the present invention, by changing the macro capacity registered in the image forming apparatus according to the condition of the display list to be created, it is possible to realize the image forming system without causing the memory shortage. Also,
Among the macros registered in the image forming apparatus, a macro storage unit for receiving and storing a macro unnecessary for printing from the image forming apparatus, and a macro not required for printing among the macros registered in the image forming apparatus. By using the macro reduction means to extract, it is possible to reduce the unnecessary macro capacity of the image forming apparatus. Furthermore, all macros registered in the image forming apparatus are saved in the host computer, and only the macros used for printing are displayed as images. Macro storage means for transmitting to the forming device,
By having only the macro capacity necessary for the image forming apparatus by the macro reducing means for receiving only the macro necessary for printing from the host computer, the image forming system can be realized without causing the memory shortage.

[Brief description of drawings]

FIG. 1 is a block diagram of an image forming apparatus according to a first embodiment of the present invention.

FIG. 2 is a block diagram of a host computer according to the first embodiment of this invention.

FIG. 3 is a flowchart of the operation of the image forming apparatus according to the first embodiment of the present invention.

FIG. 4 is a flowchart of the operation of the image forming apparatus according to the first embodiment of the present invention.

FIG. 5 is a flowchart of the operation of the host computer according to the first embodiment of this invention.

FIG. 6 is a block diagram of an image forming apparatus according to a second embodiment of the present invention.

FIG. 7 is a block diagram of a host computer according to a second embodiment of the present invention.

FIG. 8 is a flowchart of the operation of the image forming apparatus according to the second embodiment of the present invention.

FIG. 9 is a flowchart of the operation of the image forming apparatus according to the second embodiment of the present invention.

FIG. 10 is a flowchart of the operation of the host computer according to the second embodiment of the present invention.

FIG. 11 is a block diagram of a conventional image forming apparatus.

[Explanation of symbols]

 17 image forming apparatus 18 image expanding means 19 image creating means 20 macro deleting means 28 cable 29 cable 30 image forming means 31 host computer 32 information expanding means 33 information creating means 34 macro saving means 43 image forming apparatus 44 image expanding means 45 image creating Means 46 Macro deleting means 53 Cable 54 Cable 55 Image forming means 56 Host computer 57 Information expanding means 58 Information creating means 59 Macro saving means

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Claims (3)

[Claims] 1. A host computer having information expanding means for expanding image information having one page of characters, graphics, bitmap images and drawing position information into a display list for each band, and a communication means for communicating with an image forming apparatus. An image forming apparatus having an image expanding unit for expanding page data for forming an image from a display list for one page, an image forming unit for printing an image on a sheet, and a communication unit for communicating with the host computer. An image forming system characterized by. 2. The information expanding means includes an information creating means for creating a display list, and a macro save for receiving a macro unnecessary for printing from the image forming apparatus among the macros registered in the image forming apparatus and saving the macro. And an image creating means for expanding page data from a display list, and a macro reducing means for extracting macros unnecessary for printing among macros registered in the image forming apparatus. The image forming system according to claim 1, further comprising: 3. The information expanding means stores only information creating means for creating a display list and macros registered in the image forming apparatus in the host computer and used only for printing. And a macro storage means for transmitting to the
The image forming system according to claim 1, further comprising: an image creating unit that expands page data from a display list; and a macro reducing unit that receives only a macro required for printing from the host computer.