JPH05221070A - Serial printer - Google Patents

Abstract

PURPOSE:To improve printing speed relatively by omitting needless printing motion by a method wherein when an effective printing data among received printing data is printed, printing of the remainder blank data is omitted and immediately thereafter, receiving of the following printing data is made possible. CONSTITUTION:A buffer memory 30 stores one line content of a printing data. Further, a storing means stores a received printing data into the buffer memory 30. Furthermore, a data editing means takes a data excluding a blank data continued to a line end among the printing data in storing or after storing with the storing means as an effective printing data. Further, a printing scan means reads the effective printing data successively from the buffer memory 30, and prints them. Besides, it omits printing of the remainder blank data according to end of printing, and stops scanning with a printing head 40. Then, a control means 3 enables the following printing data to be received by the above-mentioned storing means and data editing means after end of printing. Consequently, printing efficiency is improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a serial printer for sequentially printing print data received from a terminal device by scanning a print head in one direction.

[0002]

2. Description of the Related Art Generally, a serial printer of this type is connected to a host computer, and when print data is received from the host computer, it prints as it is.

[0003]

However, since data indicating a blank (data "00") is also transmitted as print data from the host computer side, the conventional serial printer also receives and prints this blank data. I am trying. However, even if this blank data is printed, it is not actually printed, so that a useless printing operation is performed, resulting in problems such as wear of the head and waste of printing time.

[0004]

In order to solve such a problem, the present invention provides a buffer memory for storing print data for one line and a storage means for storing received print data in the buffer memory. , Data editing means for making data other than blank data continuous to the end of the line of print data as valid print data at the time of storage of this storage means or after storage, and effective print data are sequentially read from the buffer memory and printed A print scanning means for stopping the scanning of the print head by omitting the printing of the remaining blank data upon completion of the printing, and a control means for enabling the storage means and the data editing means to receive the next print data after the printing is completed. Be prepared.

[0005]

When the effective print data among the received print data is printed, the printing of the remaining blank data is omitted and the next print data can be received immediately, so that the unnecessary print operation is omitted. And the printing speed is relatively improved.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. FIG. 3 is a block diagram showing an embodiment of the serial printer according to the present invention. In the figure, 1 is a printer I / F connector for connecting the serial printer to a host computer (not shown), 2 is an operation unit including various keys and LEDs, and 3 is a CPU having a buffer memory.
The controller 4 includes a temperature sensor 31, a head driver 32, a motor driver 33, and a power-on reset circuit 34. The configured printer unit section 5 is a power supply section that supplies power to each section when the power switch SW is turned on.

Next, FIG. 4 is a diagram showing a situation in which printing is performed by the serial printer. This printer has 3
One line is composed of 20 dots x 8 dots, and when one line of print data is received from the host computer, one line is printed from left to right.
Upon receiving the data for one line, the printing of the next line is started from the designated home position to the left. When printing of 60 lines (240 dots / 8 dots) is completed, printing is restarted from the first line of the next page.

As described above, this serial printer is
Prior to printing, one line of print data is received from the host computer and stored in the buffer memory in the CPU 30. This one line of print data is, for example, "01" H,
8-bit hex code data such as "51" H, "AB" H, ..., Such hex code data is transmitted from the host computer for 320 data. Of course, the data "00" H (blank data) indicating no printing is included in these data. The present invention is
After receiving 320 data, data indicating no printing is detected, and this data is, for example, from the 201st data to 320
If the data is continuous between the second data, the printing operation is performed up to the 200th data, and the subsequent printing operations are omitted.

Next, FIG. 2 is a timing chart showing the operation status of each part of the serial printer. In the figure, (a) shows the operation of the head motor 41, (b) shows the printing operation of the head 40, and (c) shows the CPU 3 in the control unit 3.
0 reception operation, and (d) shows the status of this printer. Here, if the printer is in the READY state as shown in FIG. 2D, the host computer transmits the print data for one line to the printer, and at this time, as shown in FIG. Receives the print data for one line, and when the data reception is completed, the printer status is changed to the BUSY status and (a)
As shown in FIG.
Is moved from the left to the right, and the head 40 is driven to print the received print data. . In addition,
As described above, the CPU 30 searches for data indicating non-printing before printing, and even if the non-printing data is detected, it does not continuously exist until the 320th data indicating the last data. In order to prepare for printing the next line after printing the last print data (valid print data), the motor 41 is operated as shown in FIG. Start the reverse rotation of and move the head 40 to the left (home position side)
And the printer status is changed from the busy status to the ready status as shown in (d). In this way, the printer becomes ready at the same time as the motor reverse rotation start command,
While the motor reversely rotates and the head 40 returns to the print start position (home position) of the next line, the print data of the next line can be transmitted from the host computer side, and as a result, it is transmitted on the serial printer side. Print data can be received and edited to improve print efficiency.

Next, FIG. 2 shows the C in the serial printer.
It is a flowchart which shows operation | movement of PU30. That is, in step 100, reception of one line of print data transmitted by the printing operation on the host computer side is started, and in step 101, an ESC (extended character; escape character) sequence is acquired and one line of data is acquired. Print data count x (3 in this embodiment)
20) is specified. Then, in step 102, both the print data number m and the count variable n described later are set to "0",
In step 103, the print data number m is incremented by one.

Then, in step 104, "m = x?"
Determination, that is, whether the number m of print data that has already been received and whose content has been analyzed is equal to the specified print data number x for one line, that is, whether the analysis of the content of the received data for one line has been completed. Determine whether or not. However, since the analysis of the content of the received data is to be started here, it is determined to be "N0", and the process proceeds to step 105 to analyze the received data. That is, in step 105, it is determined whether the received data is non-printing data (data “00” H), and if it is “YES”, the count variable n is incremented by 1 (step 106). If such non-print data continues up to the x-th data to be finally analyzed, the printing operation for the value of the count variable n is omitted. When it is determined in step 105 that the print data is not non-print data (valid data), the count variable n is set to "0".
(Step 107). When the count variable n is determined in this way, the process returns to step 103, and the print data number m is incremented by 1 in order to analyze the next received data.

In this way, the contents of the received data are sequentially analyzed, and as a result, "m = x?" In step 104 becomes "YE."
If it is determined to be “S”, the process proceeds to step 110 and “m−n”
= 0 ”is determined. This is a judgment as to whether the contents of the received data for one line are all non-printing data, and when all the receiving data are non-printing data (“YE” in step 110)
In the case of "S"), a predetermined motor is driven without performing the printing operation to start the paper feeding for one line (step 11).
1). If it is determined that all of the received data are non-printing data (“NO” in step 110), the head 40 is sequentially moved to “mn” and printing is performed, and at the same time, printing is performed. After the end, the paper is fed by one line and the head 40 is started to move to a predetermined print start position in the left direction (step 112). Immediately after the paper feed start command in step 111 and the head movement start command in step 112, the printer state is changed from the busy state to the ready state. The received data for one line can be immediately received and edited. Thus the head 41
If the received data arrives from the host computer side while the printer is moving, the determination of "Is there print data for the next line?" In step 113 is "YES". In this case, the process returns to step 101 and the same processing as before is performed. To execute. If the print data of the next line is not transmitted from the host computer side, the process ends.

[0013]

As described above, according to the present invention,
When valid print data is printed out of the received print data, the printing of the remaining blank data is omitted and the next print data can be received immediately, so unnecessary print operation is omitted and the print speed is increased. Is relatively improved.

[Brief description of drawings]

FIG. 1 is a flowchart showing an operation of a serial printer according to the present invention.

FIG. 2 is a timing chart of each unit of the serial printer.

FIG. 3 is a block diagram of the serial printer.

FIG. 4 is a diagram showing a printing situation of the serial printer.

[Explanation of symbols]

 1 Printer I / F Connector 2 Operation Section 3 Control Section 4 Printer Unit Section 30 CPU 40 Thermal Head 41 Motor

Claims (1)

[Claims] 1. A serial printer that sequentially prints print data received from a terminal device by scanning a print head in one direction, and a buffer memory for storing print data for one line and the received print data Storage means for storing in the buffer memory, data editing means for making data other than blank data continuous to the end of the print data other than blank data during or after storage of the storage means effective print data, and the effective print data A print scanning unit that sequentially reads from the buffer memory and prints, and at the end of printing, prints the remaining blank data to stop the scanning of the print head, and after the printing is completed, the storage unit and the data editing unit A serial printer, comprising: a control unit capable of receiving print data.