JPH0693182B2 - Output device - Google Patents

Description

TECHNICAL FIELD The present invention relates to an output device for outputting character pattern information corresponding to code information input from the outside, based on dot matrix format character pattern information. is there.

[Prior Art] Conventionally, there has been an output device that outputs character pattern information corresponding to code information input from the outside, based on character pattern information in a dot matrix format that expresses characters and symbols by a set of dots.

In such a conventional output device, as shown in FIG. 3 (A), for example, even a character "." With a small number of bits forming a character pattern is similar to another character "A" with a large number of bits. Since they were stored in the same size memory area, extra information (blank information) was also stored.

[Problems to be Solved by the Invention] Therefore, in the conventional output device, extra information (blank information) increases as the number of characters used increases, and the memory use efficiency deteriorates. Since blank information is also read out uniformly, there is a problem that processing efficiency is poor.

The present invention has been made in view of the conventional problems, and stores the minimum necessary character pattern information in which blank information is deleted in a memory, thereby improving the use efficiency of the memory and the processing efficiency of the pattern information. The purpose is to provide a device.

[Means for Solving the Problems] An output device according to the present invention is an output device that outputs character pattern information corresponding to code information input from the outside based on character pattern information in a dot matrix format. For each pattern information, character pattern information in which blank information in the height direction of 1 dot unit is deleted according to each character pattern information, address information corresponding to the character pattern information, and a position for outputting the character pattern information are shown. Storage means for respectively storing output position information and height information indicating the height of the character pattern information, and the address information, the height information and the output position corresponding to the code information in response to the input of the code information. Information is read from the storage means, and the height information is read based on the read address information and height information. Reading means for reading the character pattern information for the height indicated by the information from the storage means, and for the position indicated by the output position information based on the output position information and the character pattern information read by the reading means. And a control means for outputting the read character pattern information to the output storage means.

[Operation] The character pattern information from which the blank information in the unit of 1 dot in the height direction is deleted is properly output based on the height information and the output position information stored corresponding to the character pattern information.

[Embodiment] An output device according to an embodiment of the present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 is a block diagram showing a main functional configuration of an output device according to an embodiment. In the figure, 1
Is a font memory in which a plurality of character pattern information is stored in a ROM or the like, 2 is a font table that stores various information necessary for accessing the font memory 1, 3 is the font table 2 that is accessed according to the input of code information, and is read. The reading means 4 for accessing the font memory 1 using the issued information is an external device according to the character pattern information read from the font memory 1 and the information related to the use of the character pattern information read from the font table 2. It is a control means for outputting character pattern information synchronized with the device. Therefore, the synchronizing signal from the external device is input to the control means 4.

The operation of the above configuration will be described below.

When the code information is input from the line 5, the reading means 3 accesses the font table 2 via the line 6 with a value based on the code information. FIG. 2 shows the structure of information stored in the font table for inputting one piece of code information.

In the figure, the information read based on the input of the code information includes the address information 101 indicating the address a corresponding to the character pattern information of the font memory 1, the width information 102 indicating the width b of the character pattern information to be read, and the same. The height information 103 indicating the height c and the output position information 104 indicating the output position d at which the read character pattern information is output according to the synchronization signal of the external device are included. The content of the width information 102 indicating the width b of the character pattern information is determined from the relationship with the character size, as it is generally handled as a half-width or full-width character. For example, if the structure of the font memory 1 is accessed in units of bytes, the width b of the character pattern information of a character that requires 16 bits in the horizontal direction is 2. The height information 103 indicating the height c of the character pattern information is determined by the number of vertical reading times of the number of bytes corresponding to the width b of the character pattern information.

These relationships are shown in FIGS. 3 (A) and 3 (B).

In FIG. 3 (B), an address a indicates an address corresponding to the character pattern information. The width b indicates that reading of one horizontal byte is sufficient. Height c is width b
It is necessary to read 2 times. The contents of the above-mentioned information 101 to 103 are sent to the reading means 3 via the line 7. Next, the reading means 3 sends the address a via the line 8 and subsequently executes the memory access for the number of times determined by the width b and the height c. The character pattern information read from the font memory 1 by this access is input to the control means 4 via the line 9. FIG. 3 (A) shows the data structure of the font memory according to the conventional method. However, a font area of a predetermined size is uniformly reserved in the blank portion where 1 bit pattern does not exist. It will be confirmed that it was wasteful.
According to the present embodiment, a font table 2 is additionally provided to store information on the font memory 1. However, since the size of this memory is about several bytes for one font, it is used as the entire memory. Improved efficiency is expected. Incidentally, this point will be described later.

Next, the read character pattern information must be output according to the synchronization signal of the external device. A synchronizing signal is input to the control means 4 via a line 11. Considering a CRT display device as an external device, characters are generally displayed with reference to a baseline assumed in the row direction. This relationship is shown in FIG. In the figure, a line p is a supposed baseline on the display screen, and the screen is easy to see if the bottom end of each character is displayed here. In the figure, an uppercase “A”, a lowercase “b”, and a dot symbol “·” that should be displayed in a relative positional relationship with them
It is shown. The display interval in the column direction of the screen is determined by specifying full-width characters or half-width characters as in the conventional case. Therefore, when the vertical 2 bytes of the character pattern information of the dot symbol "." Is read, it must be displayed at a position separated from the reference line p by the output position d. The output position information 104 shown in FIG. 2 holds the output position d. When the font table 2 is accessed from the reading means 3 via the line 6, the font table 2 sends the output position d of the output position information 104 to the control means 4 via the line 10. Then, the synchronized character pattern information from the control means 4 is sent via a line 12 to, for example, a video RAM (output storage means) of an external device which can be repeatedly accessed at high speed. The writing order to the video RAM is started from the byte position corresponding to the position of the baseline p, for example.
However, the control means 4 does not output the character pattern information until it receives the synchronization signal for d times in order to maintain the synchronization of the writing position. That is, the output data of this section line 12 is 0. According to this data, the video RAM first finishes writing the byte position corresponding to the baseline p and outputs a synchronizing signal. The control means 4 counts down the value d held by this synchronizing signal by one. In this way
When the value held by the control means 4 eventually becomes 0, the byte of character pattern information is output. The character pattern information is output the number of times corresponding to the height c. Subsequently, as many sync signals as necessary are sent from the video RAM to the display area, but the section control means 4 outputs 0 data again, and the next character pattern information is sent from the font memory 1 via the line 9. Wait for it to be sent. Further, regarding the display of uppercase letter "A" or lowercase letter "b" in FIG. 4, the value of the output position d is 0.

In this way, the font memory 1 used in the output device of the present embodiment efficiently stores only the effective pattern portion (minimum necessary character pattern information with blank information deleted).

Then, the output means 3 may read the minimum necessary character pattern information when the code is input.

Therefore, when the microprocessor is made to execute the function of the reading unit 3 as described above, it is not necessary to read the blank portion (blank information) of the pattern as in the conventional case, so that time is saved for other processing. Can be used.

Further, the control means 4 outputs the character pattern information in a form in which the blank portion (blank information) not stored in the font memory 1 is reproduced in synchronization with the external device.

Therefore, the external device does not need to perform any special processing on this character pattern information output.

However, since the control means 4 outputs the character pattern information according to the predetermined control method of the external device, this portion should be freely configured in relation to the external device.

Therefore, the object of the present invention is sufficiently achieved only by providing the external device with the character pattern information consisting of a valid image output on the line 9 and the output information 104 of the output position d output on the line 10. Is.

In the above-described embodiment, the method of not storing the unnecessary blank portion (blank information) in the height direction of the character pattern information in the font memory 1 has been described. It is obvious that the margin portion (blank information) can be handled by a method in which it is not stored in the font memory 1.

[Effect] As described above, according to the present invention, the usage efficiency of the font memory is significantly improved. The present inventor has investigated the degree of memory improvement for 190 character patterns of, for example, 30 × 50 dots, and has obtained a result of saving about 40% of memory.

Further, according to the present invention, since the average number of times of reading from the font memory is reduced, the average processing time for pattern output is improved accordingly.

[Brief description of drawings]

FIG. 1 is a block diagram showing a main functional configuration of an output device according to an embodiment of the present invention, FIG. 2 is a diagram showing a data structure of a font table, and FIGS. 3 (A) and 3 (B) are fonts. FIG. 4 is a diagram for explaining the relationship between the address corresponding to the character pattern information as the information on the memory and the width and height of the character pattern information. FIG. 4 is a diagram showing an example in which characters are displayed on an external device.

Claims (1)

[Claims] 1. An output device for outputting character pattern information corresponding to code information inputted from the outside based on the character pattern information in the dot matrix format, wherein each character pattern information is converted into character pattern information. Accordingly, the height of the character pattern information, in which the blank information in the height direction of 1 dot unit is deleted, the address information corresponding to the character pattern information, the output position information indicating the position at which the character pattern information is output, and the height of the character pattern information And storage means for respectively storing height information indicating the address information, the address information corresponding to the code information, the height information, and the output position information are read from the storage means and read out. The character pattern information corresponding to the height indicated by the height information is forwarded based on the generated address information and the height information. Reading means for reading from the storage means, and storage means for outputting the read character pattern information at the position indicated by the output position information based on the output position information and the character pattern information read by the reading means An output device comprising: