JPH0528405B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a printer control device that has the option of printing in any position, such as graphic printing.

[Conventional technology]

As a method of sending character pattern data to be printed by a printer control device to a printer, for example,
As shown in Publication No. 59-4706, a method is provided in which data on the same raster among each character pattern in one line is sequentially sent to a printer, and a page memory is provided to store print pattern data for one page. There is a method in which all print patterns for one page are developed into a page memory, and then the contents of the page memory are read out in the raster direction and sent to the printer.

The latter is usually used when printing graphic data. The dot data capacity of graphic data requires two pages of page memory, that is, full dot memory (hereinafter abbreviated as FDM).
At least one side is necessary because print data is to be developed at an arbitrary position on the page, and the other side is necessary for continuous printing. In other words, while printing, the next page is developed on a different side.

In this control device that has graphic printing as an option, dot data development of only character data is controlled using two FDMs. When controlling only character data, it is possible to send print data using the former method without having an FDM, but the control method is different and the control becomes complicated.

[Problem that the invention seeks to solve]

The above-mentioned conventional technology does not take into account the memory capacity when controlling the expansion of dot data of only character text, resulting in a problem of high cost.

It is an object of the present invention to provide a kanji printer control device that solves these conventional problems, makes little change in control over text-only and graphic print data, reduces FDM memory capacity, and improves economic efficiency. Our goal is to provide the following.

[Means for solving problems]

In order to solve the above problem, in a printer control device that has a full dot memory that can store one page worth of dot data, there is an effective function that indicates that a 1-bit dot has been expanded to a specific capacity of data in the full dot memory. has a bit, and sets the valid bit when writing dot data,
means for resetting when reading during printing, and error detecting means for waiting for the effective bit to become 0 if it is 1 before writing the dot data, and then writing it, and detecting a printing error if it is 0 when reading. There are certain characteristics.

[Effect]

An effective bit is set for each certain amount of dot data,
A certain amount of dot data is set when writing,
Reset by reading when printing.

If the valid bit is 1 at the time of writing, it means that it has not been printed yet, so wait until it becomes 0.
On the other hand, if the value is 0 when reading, it is assumed that there is no data to be printed and an error occurs.

〔Example〕

Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram of a kanji printer control device showing one embodiment of the present invention.

In FIG. 1, 1 is a font memory that stores various font data, 2 is a fetch buffer that fetches each data, 3 is an editing section that enlarges/reduces the fetched font data as necessary, and 4 5 is a store buffer that stores edited font data or valid bits to check whether the expanded area of FDM5 has already been printed, and 5 is a full dot memory (FDM) that can store one page of dot data. , 6 is a memory bus for transferring font data, 7 is an FDM bus for transferring data to the FDM 5, and 8 is a buffer storage for temporarily storing dot data written in the FDM 5 before sending it to the printer 13. , 9 is a raster control unit that performs raster control of data in the FDM 5; 10 is an overrun check control unit that checks overrun of dot data to the printer 13; and 11 is a validity check of dot data stored in the buffer storage 8. and a valid bit determination/error detection section for detecting errors; 12 is an address control section for selecting an FDM address of a valid bit; and 13 is a printer. The operation shown in FIG. 1 will be explained below.

Before expanding the font data in the font memory 1 to the FDM 5, a valid bit is read to confirm whether the area to be expanded has already been printed. It is read into the store buffer 4 via the FDM bus 7. If the valid bit is 1, it is assumed that the previous dot data has not been read and it waits until it becomes 0. If it is 0, the font data in the font memory 1 is input from the character data code to the fetch buffer 2 via the memory bus 6. If the data needs to be enlarged/reduced, the editing section 3 edits it. After that, it is input to store buffer 4,
Written to FDM 5 via FDM bus 7.
When writing to the FDM 5, one valid bit is added to a certain amount of data.
For example, data is written in raster units with one bit being the effective bit.

On the other hand, the written dot data is read from the FDM bus 7 to the buffer storage 8, but before that, the valid bit written in the FDM 5 is checked. The checking stage is performed before sending the first dot data of the raster to the printer 13. This is created by the raster control section 9 and input to the overrun check control section 10. The overrun check control section 10 has a fixed value of the effective bit address, and the effective bit address is fixed.
Address control unit 1 to select FDM address
2, and the valid bits on the FDM 5 are taken into the buffer storage 8. Note that a signal line for specifying FDM〓 or FDM(1) is input to the address control unit 12. This is set to a fixed value by the microprogram when there is no graphics option and will not be changed thereafter. When the graphics option is used, each page is reversed. The output of the buffer storage 8 is input to a valid bit determination/error detection section 11, where a 0/1 determination is made. If it is 0, the dot data to the printer 13 cannot be delivered in time, so an overrun is detected. In this case, error recovery is performed.
Error recovery is performed page by page. The data already sent to the printer has been developed on the drum and has not yet been transferred to paper. The development data on this drum is erased and the print data is once again developed onto the FDM5.

FIG. 2 is a comparison diagram of an example of FDM expansion operation according to the present invention and a conventional example of FDM expansion operation. here,
a is an example of conventional FDM expansion operation of character data with/without a graphics option, b is an example of FDM expansion operation of character data with a graphics option according to the present invention, and c is an example of character data without a graphics option according to the present invention. An example of FDM expansion operation is shown.
Hereinafter, the conventional FDM expansion operation and the FDM expansion operation of the present invention will be explained while comparing them.

First, the conventional FDM expansion operation will be explained using FIG. 2a. When writing graphic data to FDM when the graphic data option is available, first expand it to FDM〓. Dot data is written at any position. Since there is character data on that page, after reading FDM,
Take orer and write. The character data is sent line by line from the host CPU (not shown), so
As shown in (a), the FDM addresses are written in ascending order. When one page of dot data is written to the FDM, the FDM is sequentially read out and output to the printer in order to send the dot data to the printer. Then expand in the same way to output the next page to FDM(1). The same applies if the page has no graphic data and only character data, or if the page has only character data for which graphic printing is not an option.

When performing graphic printing as described above, dot data is written at arbitrary positions, so it is necessary to have a buffer for one page. Normally, if you try to print continuously, there will be a buffer of two pages. Therefore, in a Kanji printer control device that has graphic printing as an option, control without the option, that is, control of only character data, is performed in exactly the same manner as with the option.

However, since character data can originally be printed line by line sequentially, the buffer for dot data can be small. If the above method is adopted, the control method will be different depending on whether there is an option or not, resulting in complicated control.

Therefore, in the present invention, FDM expansion as shown in FIGS. 2b and 2c is performed.

First, the development of only character data in FIG. 2c will be explained. One page of FDM is prepared, and valid bits are prepared there in addition to dot data. The effective bit control is as shown in FIG. The flow of this control is as follows. Expand one page of data to FDM. Then print.
Next, expand the next page to FDM〓. This is done after printing the dot data of the characters corresponding to the valid bits on the previous page. in this way
Print data and next page development data coexist on FDM. Next, a case where graphic printing is provided as an option will be explained with reference to FIG. 2b. This is the same as the conventional method shown in FIG. 2a, except that a valid bit according to the present invention is provided. Control of the effective bit may be the same as in FIG. 2c.
That is, when writing dot data, the valid bit is set to 1, and when reading it, it is set to 0. Since it is never 1 when writing, no waiting occurs. On the other hand, it is never 0 when read.

As mentioned above, the difference in control of FDM expansion of character data when there is a graphic printing option and when it is not is simply a change in the tightness of the expansion and print instructions.

In this way, in this embodiment, one free bit is provided on the FDM for each fixed character dot data unit, and the FDM can be reduced by at least one page simply by changing the dot development instruction method. Since the dot expansion instruction can be performed under program control, the only hardware resources that need to be provided are valid bit determination and error detection sections.

〔Effect of the invention〕

As described above, according to the present invention, the memory capacity of the FDM can be reduced, and the economical efficiency of the apparatus can be improved, with almost no change in the control regarding print data for only text and graphics.

[Brief explanation of drawings]

Fig. 1 is a block diagram of a kanji printer control device showing an embodiment of the present invention, and Fig. 2 is an FDM according to the present invention.
FIG. 3 is a comparison diagram of an example of an expansion operation and a conventional example of an FDM expansion operation. 4: Store buffer, 5: FDM, 6: Memory bus, 7: FDM bus, 8: Buffer storage,
9: Raster control section, 10: Overrun check control section, 11: Valid bit judgment/error detection section, 1
2: Address control section.

Claims (1)

[Claims] 1. In a printer control device having a full dot memory capable of storing one page worth of dot data, the printer control device has a valid bit indicating that a 1-bit dot has been expanded to a specific capacity of data in the full dot memory, and the dot data Means for setting the valid bit when writing and resetting it when reading when printing, and if the valid bit is 1 before writing the dot data, wait until it becomes 0 before writing, and if it is 0 when reading, print. 1. A printer control device comprising: error detection means for detecting an error.