JPH01204758A - Dot printer - Google Patents

Abstract

PURPOSE:To enable a slant character of high quality to be printed without increasing a capacity of a memory, by a method wherein two column data mask-treated according to a slant direction or a printing direction from one column content of data of a slant character pattern are prepared at timing when printed by two times resolution. CONSTITUTION:A character pattern stored in a, CGROM is slanted at equimultiple resolution, and is developed in an image buffer (a). A first and a second data preparation means (b) and (c) mask-treat an upper and a lower bit of data of one column in a slant character pattern, for instance, each 4 bits according to a slant direction or a printing direction and prepare a first and a second column data. Then, a timing control means (d), every time a printing time signal in printing at two times resolution supplied from a motor controlling controller is received, operates alternately the first and the second data preparation means (b) and (c). Thereby, the two column data are successively at printing timing of two times resolution transferred to a head buffer (e), and this procedure is repeated on each column in the slant character pattern to perform printing.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a dot printer capable of printing high quality slant characters.

(Prior Art) Figure 2 shows an example of a dot pattern of characters and symbols (hereinafter simply referred to as characters) used when printing with a dot printer. ) is stored in correspondence with a predetermined character code.

Figure 3 shows the pattern developed on the image buffer set in the random access memory in the printer (hereinafter referred to as slanted characters) when printing slanted characters or symbols (hereinafter referred to as slanted characters) with a conventional printer. (referred to as a slant character pattern), and Fig. 3(a) shows an example of a printer that develops and prints the aforementioned dot pattern slanted at the same resolution. (
b) shows an example of another printer that slants and prints the aforementioned dot pattern at twice the resolution.

(Problem to be solved by the invention a) However, the above-mentioned printer 1 can only obtain low-quality printing results, and the other printers mentioned above can obtain high-quality printing results, but the printer 1 mentioned above can only obtain low-quality printing results. There was a problem in that the image buffer required twice the capacity compared to .

SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems and provide a dot printer that can print high-quality slant characters without increasing memory capacity.

(Means for Solving the Problem) In order to achieve the above object, the present invention prints slant characters based on a slant character pattern created by slanting character patterns stored in a read-only memory at the same resolution. In a dot printer that performs printing, first column data is created by masking the upper or lower bits of data in one column in a slant character pattern for each predetermined number of bits in accordance with the slant direction or printing direction. and creating second column data by masking the lower or upper bits of the data of the first column in the slant character pattern in accordance with the slant direction or printing direction for each predetermined number of bits. A second data creation means and a timing control means for alternately operating the first and second data creation means in accordance with the timing when printing at twice the resolution are provided.

(Function) According to the present invention, the first and second column data are masked according to the slant direction or printing direction from one column of data of a slant character pattern developed at the same resolution. is created at the timing when printing at double resolution, and this drives the print head,
Printing is performed.

(Embodiment) FIG. 1 is a functional block diagram showing an outline of a dot printer of the present invention.

The character pattern stored in the CGROM is slanted at the same resolution using a well-known method, converted into a slanted character pattern, and expanded into the image buffer a.

The first data creation means converts the data of one column in the slant character pattern into a predetermined number of bits, for example, every 4 bits, and converts the upper or lower bits (for example, the right italics in order) according to the slant direction or printing direction. In the case of printing in the direction, the first column data is created by masking the upper 2 bits of the 4 bits, and the second data creation means C also creates the data of the first column by a predetermined bit. number,
For example, for every 4 bits, the lower or upper bits are masked according to the slant direction or printing direction (for example, when printing right italics in the forward direction, the lower 2 bits of the 4 bits) are masked and the second column is printed. Create data.

The timing control means d alternately controls the first data creation means and the second data creation means C every time it receives a printing timing signal for printing at double resolution supplied from a well-known motor control controller. make it work.

Therefore, the first column data and the second column data are sequentially transferred to the head buffer e at double resolution printing timing, and a print head (not shown) is driven via a head driver (not shown). This is repeated for each column data in the slant character pattern, and high quality slant characters are printed.

FIG. 4 shows the hardware configuration of an embodiment of the dot printer of the present invention, in which 1 is a microprocessor (CPU), 2 is a read-on memory (ROM), and 3 is a microprocessor (CPU).
is CGROM, 4 is random access memory (RAM)
, 5 is an I10 interface circuit, 6 is a motor controller, 7 is a motor driver, 8 is a head driver, 9 is a print head, and 10 is a bus.

The ROM 2 stores programs for executing various controls, and the CGROM 3 stores dot patterns (character patterns) of characters and symbols in correspondence with character codes, as described above. The RAM 4 includes an image buffer 11 for storing slant character patterns and a head buffer 12 for temporarily storing one column's worth of data after conversion processing, which will be described later. The I10 interface circuit 5 exchanges printing-related data with a host device, such as a personal computer.

The motor controller 6 generates various timing signals for driving and controlling an LF motor (not shown) for printing paper line feed and a spacing SP motor for moving the print head 9 in the printing direction. The motor driver 7 drives the aforementioned LF motor and SP motor, and the head driver 8 drives the print head 9.

In the device, when the CPUI receives data related to printing, that is, control data and a character code via the I10 interface circuit 5, it reads a corresponding character pattern from the CGROM 3 using the character code as an address. Here, if the control data specifies printing of slant characters, the CPU 1 slants the read character pattern at the same resolution using a well-known method, and prints the character pattern in the image buffer 1.
Develop a slant character pattern on 1. The slant character pattern at this time is similar to the pattern shown in FIG. 3(a) described above.

Next, the CPUI converts one column data in the image buffer 11 into first and second column data.

Figure 5 shows the correspondence between pattern data and data in the image buffer. Figure 5 (a) shows that each column of pattern data is 1-byte data ■, ■, ■, ■.
, ■, ■, . . . are each made up of 3 bytes, and FIG.

2, 2, 2, . . . indicate that addresses (IMGRDP) are assigned and stored one byte at a time in numerical order.

FIG. 6 shows the flow of processing for converting the data in one column in the image buffer 11 into first and second column data and printing them. The printing operation of slant characters will be explained below in accordance with this flow.

First, the CPU 1 performs initial settings (step S11).
S2), the number of bytes of data for one column "3" is set in the internal general-purpose register R6 (step s3). Next, the read address of the image buffer 11 (IMGRD
P) is set in the internal data pointer (DPTI?) (step s4), and the read 1-byte data is loaded into the internal accumulator (ACC) (step s5).
).

Next, the flag SW for distinguishing between the first and second column data is checked (step s6), but since it has been reset at this point, that is, it is "0", the data in the accumulator (ACC), i.e. image buffer 1
1 and the mask data D1, here r33HJ ("roollooll" when expressed in binary) (step s7).

To set the data after the above calculation in the head buffer 12 (step s8), update the data pointer (DPTI?) to retrieve the second byte data, that is, add "1" (step s9), and set the value of register R6. is updated, that is, "1" is subtracted (step s10).

Next, in order to confirm whether one column of data has been converted, it is checked whether the value of register R6 is "0" (step 511). If (R6)≠0, the operations from step 85 to sio described above are repeated. (R6) If it is -0, it is assumed that the conversion of one column of data has been completed, and the flag S
Check W (step s12). At this point, it remains reset, so the flag SW is set, that is, "1".
” and step 513), the converted 3-byte data, that is, the first column data, is taken out from the head buffer 12 and set in the head driver 8 (step 81).
4).

Thereafter, when the motor controller 6 outputs a print timing signal for printing at twice the resolution, the head driver 8 operates and the print head 9 performs printing.

FIG. 7 shows an example of a printing result according to the present invention. At this point, only one column of data A is printed.

Detecting the printing timing signal (step s15)
), it is checked whether printing is finished (step 816), but
At this point, the process is not finished yet, so the process returns to step s3.

At this time, the read address (IM
Since GRDP) has not been updated, the data in the same column as last time is used and the processing of steps 83 to S11 is repeated. However, at this point, the flag SW is set, that is, "1", so the accumulator (A
ce) is mask data D2, here rCCHJ (rllooll if expressed in binary)
ooJ) (step 517).

The processing of steps s5 to s11+s17 is 3
It is repeated several times, 3 bytes of data is converted, and step S1
When the process proceeds to step 2, since the flag SW is set at this point, the printing direction is checked (step 81B). The printing direction is initially forward (usually going to the right),
At this point, it is still in the forward direction, so the image buffer 11
The read address (IMGRDP) of is updated, that is, “+3
” (step 819), and further mask data Di,
Resetting D2 (step 520) and resetting the flag SW (step 521) are executed.

Thereafter, the 3-byte data converted in the same manner as described above, that is, the second column data, is set in the head driver 8,
Printing is executed by the print head 9, and data B in FIG. 7 is printed.

Note that if the printing direction is reverse, the image buffer 11
The read address (IMGRDP) of is updated by "-3" (step 522), and the mask data DI,
D2 is set to a value opposite to that in the forward direction (step 823).

By repeating the above-mentioned process for all column data on the image buffer 11, the slant character pattern data developed at the same resolution can be used to create high quality data that is equivalent to when developed at twice the resolution. slant characters are printed.

In the above embodiment, the case where right-hand italic slant characters are printed is explained as an example, but it goes without saying that left-hand italic slant characters can also be printed in the same way by simply replacing the mask data Di and D2.

(Effects of the Invention) As explained above, according to the present invention, from one column of data of a slant character pattern developed at the same resolution, the first And because the second column data is created at the same time as printing at double resolution,
By using an image buffer capable of storing the slant character pattern developed at the same resolution, high-quality slant characters can be printed as in the case of using the slant character pattern developed at twice the resolution.

[Brief explanation of the drawing]

FIG. 1 is a functional block diagram showing an overview of the dot printer of the present invention, FIG. 2 is a diagram showing an example of a character pattern, FIG. 3(a) is a diagram showing an example of a slant character pattern, and FIG. 3(b) is a diagram showing an example of a slant character pattern. Figure 4 shows another example of slant character pattern.
The figure shows the hardware configuration of an embodiment of the dot printer of the present invention, FIGS. 5(a) and 5(b) show the correspondence between pattern data and data in the image buffer, and FIG. 6 shows the slant character. FIG. 7, which is a flowchart of processing related to printing, is a diagram showing printing results according to the present invention. b...first data creation means, C...second data creation means, d...timing control means. Patent applicant Oki Electric Industry Co., Ltd.

Claims (1)

[Claims] In a dot printer that prints slant characters based on a slant character pattern created by slanting a character pattern stored in a read-only memory at the same resolution, one column in the slant character pattern is provided. a first data creation means for creating first column data by masking the upper or lower bits of the data for each predetermined number of bits corresponding to the slant direction or printing direction; a second data creation means for creating second column data by masking the lower or upper bits of the column data for each predetermined number of bits corresponding to the slant direction or printing direction; A dot printer characterized in that it is provided with timing control means for alternately operating the data creation means in accordance with the timing when printing at double resolution.