JP2687478B2 - Printing device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a laser beam printer, a wire dot printer, which prints image data on a RAM based on input data input from a host computer or the like.
The present invention relates to a printing device such as a printer.

2. Description of the Related Art Conventional technology will be described below with reference to the drawings.

FIG. 4 is a schematic configuration diagram of a conventional printing device. In the figure, 1 is an interface unit that receives data from a host computer (hereinafter simply referred to as host), 2 is a text creation unit that analyzes the data received from the host 1 and converts it into image developable internal data, and 3 is text creation An image expansion unit that expands the actual print image data based on the text created by the unit 2 and an image expansion area (video band buffer (hereinafter referred to as VBB)) that stores the expanded print image data And
It is composed of random access memory (hereinafter referred to as RAM). Reference numeral 5 denotes a printing unit that takes out the print image data on the VBB at a predetermined timing and prints it on the paper as characters or images.

The VBB4 print image data can be expanded only in a region corresponding to a fraction of the print range of the paper.

The operation of the conventional printing apparatus having the above-described structure will be described below.

First, the data (character code) received from the host via the interface unit 1 is given information by the text creating unit 2 (information indicating the writing position in the VBB, etc.).
Is added and temporarily stored there. In this way, when the text corresponding to one page is created and stored, the print image data is sequentially developed from the beginning of the text and stored in the VBB4. When the print image data corresponding to the capacity of the VBB4 is stored (the state is shown in FIG. 5), the printing unit 5 takes out the print image data for each raster and prints characters or images on the paper. To form. When the print image data is taken out for each raster in this way, an empty area is generated in VBB4 each time (see FIG. 6). When an empty area is created, the text creation unit 2 stores print image data corresponding to the characters and images in the next line. By repeating such a series of operations, one page of characters can be displayed.

However, since the size of the VBB is fixed in the above conventional technique, when the amount of characters or images to be printed in one page increases, the speed at which the printing unit 5 retrieves and prints the image is increased. On the other hand, a so-called overrun error occurs in which the characters and images on the VBB cannot be expanded in time.

In order to solve the above-mentioned conventional problems, the present invention stores a first area for storing at least one page of text data and print image data in which this text data is sequentially expanded from the leading end. A storage unit having a VBB, a text creating unit that creates and stores text data in a first area based on input character code data, and a text data stored in the first area in order from the tip. Image expansion means for expanding the print image data and storing it in the VBB, printing means for sequentially extracting the print image data from the VBB from the leading edge and printing, and for one page input and stored in the first area A data amount determination means for determining the amount of data, and if the amount of data of this data amount determination means is large, increase the capacity of VBB occupying in the storage means, If the capacity is small, a capacity setting means for reducing the capacity of VBB occupied in the storage means is provided.

By the above means, the present invention is suitable for the contents of input data.
The size of the VBB can be set, the occurrence frequency of overrun errors can be greatly reduced, and the entire memory including the VBB can be effectively used.

Practical Example FIG. 1 is a configuration diagram showing the configuration of a printer according to an embodiment of the present invention.

In the figure, 1 is an interface section, 2 is a text creating section, 3 is an image developing section, 4 is a VBB section, and 5 is a printing section. The above is the same as the configuration of the conventional example. 6 is a data amount discriminating unit for discriminating the amount of data for one page created by the text producing unit 2, and 7 is a VBB amount setting unit for setting an optimal VBB amount for the data amount discriminated by the data amount discriminating unit 6. is there.

FIG. 2 is a block diagram showing the actual circuit configuration of the printing apparatus of the embodiment.

In the figure, 8 is a CPU (central processing unit) that executes instructions according to a program stored in advance in a ROM (Read Only Memory) 9, 10 is an interface for communicating data with a host computer, and 11 is VBB capacity setter that sets the capacity of VBB, 12 is random access
Memory (hereinafter referred to as RAM), VBB4 is provided in RAM12. The text data created by the text creating unit 2 is also stored in the RAM 12 in an area different from the area occupied by the VBB4. Reference numeral 13 is a printing unit, which actually prints based on VBB4 data.

The operation of the printing apparatus of this embodiment constructed as described above will be described below with reference to the flowchart shown in FIG.

First, input character data for one character from the host computer (step (a)) and create a text corresponding to the character data (step (b)). At this time, set the value of the counter that counts the data number. Increment by 1 (step (c)), determine whether the text creation for one page is completed (step (d)), and if not completed, return to step (a) to fetch the next data . If it is finished, check whether the count value of the data counter exceeds 10,000.
The CPU8 determines (step (e)), if it exceeds, calculates the VBB capacity as 128KB (step (to)), and if the count value does not exceed 10,000, whether the count number exceeds 5,000 or not CPU8 determines (step (g)), if it exceeds VKB capacity is calculated as 64KB (step (h)), if not exceeded, VBB capacity is calculated as 48KB (step (re)), above VB calculated as
According to B, the CPU 8 controls the VBB capacity setting unit 11 to set the VBB capacity (step (nu)), then starts the development of the print image data for the VBB (step (ru)), and the VBB
It is judged whether the expansion of the print image data of the possible capacity is completed, that is, whether the initial expansion is completed, and if it is not completed (step (wo)), wait until the completion
If it is finished, printing is started (step (W)). The printing operation of step (wa) is as described in the conventional example. According to this embodiment, when the amount of data for one page is large, the capacity of VBB is increased, and the data which can be printed on VBB is expanded before the start of printing. Can be suppressed 1
When the amount of data for a page is small, the capacity of VBB can be reduced so that the RAM can be used for many purposes other than VBB, so that the effective use of RAM can be achieved.

According to the present invention, the first area for storing at least one page of text data, the storage means having the VBB for storing the print image data in which the text data is developed in order from the head, the input character code, etc. First based on data
Of the text data stored in the first area, and the image expansion means for expanding the print image data and storing it in the VBB in order from the beginning of the text data stored in the first area, and the printing from the VBB. Printing means for sequentially taking out image data from the leading end and printing, data amount determining means for determining the amount of data for one page that is input and stored in the first area, and data of this data amount determining means If the amount is large, occupy the storage means
When the amount of data is large, the capacity of VBB is increased to increase the capacity of VBB by increasing the capacity of VBB. This has the effect of increasing the amount of data and reducing the frequency of occurrence of overrun errors.When the amount of data is small, the VBB capacity is reduced and the reduced memory capacity is used for other purposes. Therefore, the memory can be effectively used, which is very effective.

[Brief description of the drawings]

1 is a block diagram showing the configuration of an embodiment of the present invention, FIG. 2 is a block diagram showing the actual circuit configuration, FIG. 3 is a flow chart showing the operation, and FIG. 4 is a block diagram showing the configuration of a conventional example. , Fifth
FIG. 6 is an explanatory diagram showing the expansion of character data on the VBB, and FIG. 6 is an explanatory view showing the relationship between the expansion of character data on the VBB and printing. 1 ... Interface part, 2 ... Text creation part, 3
...... Expansion unit, 4 ... VBB unit, 5 ... Printing unit, 6 ... Data amount determination unit, 7 ... VBB amount setting unit.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP 62-88025 (JP, A) JP 61-100472 (JP, A) JP 61-195865 (JP, A) JP 2- 52763 (JP, A) JP 2-30557 (JP, A) JP 59-3625 (JP, A)

Claims (1)

(57) [Claims] 1. Storage means having a first area for storing at least one page of text data and a second area for storing print image data obtained by sequentially expanding the text data from the leading end, and input characters. A text creating unit that creates and stores text data in the first area based on data such as a code, and print image data that is sequentially expanded from the leading end of the text data stored in the first area to create the second area. Image expansion means for storing in the area, and the second
Area, the print means for sequentially taking out the print image data from the leading edge and printing, the data quantity judging means for judging the quantity of data for one page which is inputted and stored in the first area, and the data quantity. A capacity setting for increasing the capacity of the second area in the storage means when the amount of data of the determination means is large, and for decreasing the capacity of the second area in the storage means when the amount of data is small. A printing device comprising means.