JPH0794178B2 - Printer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention notifies a higher-level device that a printer, and more specifically, a sheet set in the printer has reached a printable end of a print head. The present invention relates to a printer in which the timing of sending paper end information is improved.

(Prior Art) FIGS. 3 to 5 are drawings relating to a conventional printer having paper end information.

FIG. 3 is a block diagram of a conventional printer. In the figure, print data output from a host computer (not shown) is transmitted via the interface input / output circuit 1.
Input to CPU2. The CPU 2 processes the print data according to the procedure stored in the program ROM 15 in advance, and prints by operating the print head 4, the space motor 6, and the line feed motor 8 via the print head driver 3, the space motor driver 5, and the line feed motor driver 7, respectively. Do. Further, a paper end sensor 9 for detecting the end of printing paper (hereinafter, also referred to as paper end) is connected to the CPU 2, and is sent to the host computer via the interface input / output circuit 1 based on the value of the line feed number counter 12. It is possible to output the paper end information and stop the output of the print data.

FIG. 4 is a side view of this type of printer, which shows the printing paper 16
Is clamped by a liner motor 8 (see FIG. 3) and a rotatable platen 17 which is coupled by a gear (not shown) and the like, and the paper chute is rotated by the line feed motor 8 in the direction of the arrow in the figure. Paper is sent along line 18. At this time, the print head 4 performs printing while moving in the direction perpendicular to the plane of the drawing by the space motor 6. Further, the paper end lever 19 is outside the paper end sensor 9 as shown by the solid line in the figure when the printing paper 16 is in the lever position, but when the printing paper 16 is fed and its end exceeds the lever position. , And falls into the paper end sensor 9 as indicated by the dotted line in the figure, and the CPU 2 detects the end of the paper. In the figure, 1 is the length of the paper route from the position where the paper end lever 19 detects the end of the paper to the printing position.

Further, FIG. 5 is a paper end processing flowchart in the printer having the above configuration. Next, the operation of the printer will be described with reference to this figure.

First, as described above, printing is performed on the printing paper 16 by the printing data sent from the host computer, and the printing paper 16 is moved in the direction of the arrow in FIG. Printing paper at this time
When the end of 16 is released from the paper end lever 19, the paper end lever 19 falls inside the paper end sensor 9, and the CPU 2 detects the end of paper (S1). However, at this point, the margin α at the bottom of the paper is still more than the length l in FIG.
The remaining printable paper is L = 1-α.
Therefore, after detecting the end of the paper, the CPU 2 accumulates the line feed amount in the line feed counter 12 for each line feed operation, and the line feed counter 12
If the content of is equal to or larger than L (S2), paper end information is sent to the host computer via the interface input / output circuit 1 (S3), and sending of print data is stopped, so that the bottom edge of the paper is stopped. Printing is possible up to near.

(Problems to be Solved by the Invention) However, in the above-described conventional printer, when the output of the host computer is stopped before the paper end sensor detects the end of the paper by the normal operation and the paper is removed for the paper replacement, By this, the paper end sensor is turned on, the counting of the line feed number count register is started, and the paper end information is not output until the count number ≦ L.
Therefore, if the output of the host computer restarts due to some erroneous operation or malfunction, the printer will perform blank printing if no paper is set in the printer.

Further, as a measure to prevent this, it is conceivable to dispose a paper end sensor in the immediate vicinity of the print head so as to output the paper end information at the same time as the paper end detection.
Generally, there are many movable parts in the vicinity of the print head, and if an attempt is made to install a paper end sensor, the structure becomes more complicated and the cost increases.

SUMMARY OF THE INVENTION It is an object of the present invention to eliminate the problem that a conventional printer performs blank printing and shortens the life of the print head, and to provide a printer with excellent cost performance.

(Means for Solving the Problem) According to the present invention, a paper end detection sensor is arranged apart from the print head, and the last line position of the printable paper of the paper is detected after the paper end detection sensor detects the line end. In a printer set by the count number of a number counter, a data processing flag memory that stores information indicating that the printer is receiving data only from a host device, and a printing operation only when the printer is printing The print end flag memory for storing information indicating that the paper end information is connected to each of the paper end detection sensor, the line feed number counter, the data processing flag memory, and the print operation flag memory, and outputs the paper end information. A CPU for controlling the timing of output to the higher-level device, and the CPU (a) before detecting the paper end by the paper end detection sensor. When neither the information indicating that data is being received in the data processing flag memory nor the information indicating that a printing operation is being performed in the printing operation flag memory is present, the paper is pulled out and the paper end detection sensor detects Means for immediately outputting the paper end information to the upper device when the end is detected; (b) information indicating that data is being received in the data processing flag memory and printing operation in the printing operation flag memory After the paper end detection sensor detects the paper end with either of the information indicating that the data is present, the data is transferred while the paper end reaches the final line position set by the line feed counter. Change to a state where neither the information indicating that data is being received in the processing flag memory nor the information indicating that printing is being performed in the printing operation flag memory exists. Immediately, the paper end information is output to the higher-level device, and while the paper end reaches the final line position set by the line feed counter, data is being received in the data processing flag memory. If either the information or the information indicating that the printing operation is in progress in the flag memory is still present, printing is performed until the final line position is reached, and then the paper end information is sent to the upper device. And a means for outputting, a printer.

(Operation) The printer of the present invention is the same as the conventional printer of the type described above.
The configuration is the same as that in which the receiving flag memory and the printing operation flag memory are provided.

Therefore, the CPU of the printer of the present invention uses the paper end sensor in the normal operation of the conventional printer (the operation in which printing is normally performed, the paper end is detected, and after the count L, the paper end information is sent to the host device). In addition to the information from, information about whether data is being received and whether the printer is printing is available. Then, when the output of the paper end sensor is on and both the data receiving flag memory and the printing operation flag memory are off, the paper end information is sent to the host device.

FIG. 6 is a timing chart of paper end information transmission in the case other than the normal operation. In cases other than normal operation, (a)
If the data reception and printing operations are completed before the end of L,
(B) The case where the printer is stopped and the paper is artificially pulled out before the start of L is cited. In the conventional printer, in the case of (a), it is handled as normal operation, and as described above, when the paper end sensor is turned on by pulling out the paper after the output of the host computer is stopped, there is a possibility of blank printing. there were. In the case of (b), there is a possibility of blank printing for the same reason as in the case of (a). On the other hand, in the present invention, in the case of (a), the paper end information is sent out when the data receiving and printing operations are completed. Further, in the case of (b), the printer is stopped, that is, the data reception and the printing operation are stopped, and the paper end sensor is turned on by artificially pulling out the paper, the paper end information is sent out, and remains in the upper device side. Blank printing is avoided by erroneous operation of print data (indicated by a broken line in the figure).

In other words, in both cases (a) and (b), the line feed counter starts counting when the paper end sensor detects the end of the paper, but after this start, even before the end of L, the printer When the printing operation is not performed and the data is not received, the paper end information is quickly output.

(Example) Hereinafter, the Example of this invention is described with drawing.

FIG. 1 is a configuration block diagram showing an embodiment of the present invention.

In the figure, interface input / output circuit 1, CPU 2, print head driver 3, print head 4, space motor driver 5, space motor 6, line feed motor driver 7,
Line feed motor 8, paper end sensor 9, line feed number counter
Since 12 is the same as the above-mentioned conventional example, the same number is assigned.
Further, in the data receiving flag memory 13 connected to the CPU2, information indicating that the printer is receiving data only while the printer is processing received data is written, and in the printing operation flag memory 14 also connected to the CPU2, Information indicating that the printer is printing is written only when the printer is printing. Program ROM1
The processing procedure of the CPU is stored in 0. The configuration of the printing unit is the same as in FIG.

Next, the operation of the apparatus having the above configuration will be described.

The normal operation is the same as the above-mentioned conventional example. That is, the printer prints, the end of the print paper 16 passes over the paper end lever 19 and falls into the paper end sensor 9, and the CPU 2 detects the end of the paper. The CPU 2 further refers to the data receiving flag memory 13 and the printing operation flag memory 14 while the print data is continuously sent from the host computer and the data reception and the printing operation are continuously performed. Similar to the conventional example, the line feed number counter 12 is integrated, and after the end of the paper is detected, the length L is printed, and then the end of paper information is output to the host computer via the interface input / output circuit 1.

After the paper end is detected, the data reception and the printing operation are completed before the end of L [Fig. 6 (a)], or the paper is pulled out when the printer is stopped before the paper end is detected. When the sensor is turned on [Fig. 6 (b)], the CPU 2 detects that neither the data reception nor the printing operation is performed by the data receiving flag memory 13 and the printing operation flag memory 14. Then, it detects that the paper end sensor 9 is turned on and immediately outputs the paper end information to the host computer.

FIG. 2 is a flow chart showing the above paper end processing. According to this, the contents of paper end processing are summarized as follows. When the paper end sensor 9 detects the end of the paper (S10), the printing operation flag memory 14,
If it is turned off together with the data receiving flag memory 13 (S11, S12), the paper end information is immediately output (S14),
Otherwise, when the line feed number counter 12 becomes L or more (S13), the paper end information is output (S14).

(Effects of the Invention) As described in detail above, the present invention has the above-described configuration. Therefore, according to the present invention, when the paper is pulled out by hand while the printer is stopped, the paper is immediately terminated. Information can be sent to stop sending data to the printer of the host computer, and blank printing can be prevented.

Moreover, since the structure is simple, a device with high cost performance can be realized.

Furthermore, when the computer continuously sends the print data, it is possible to print up to near the lower end of the print paper without waste.

[Brief description of drawings]

FIG. 1 is a configuration block diagram showing an embodiment of the present invention, and FIG.
The figure is a paper end processing flowchart in the present invention,
FIG. 3 is a block diagram of a conventional printer having paper end information, FIG. 4 is a side view of a printing unit of the conventional printer, FIG. 5 is a flowchart of a conventional paper end process, and FIG. 6 is a case other than normal operation. In the timing chart for sending the paper end information,
(A) shows the case where the data receiving and printing operations are completed before the end of L, and (b) shows the case where the printer is stopped and the paper is pulled out before the start of L. 2 ... CPU, 9 ... Paper end sensor, 12 ... Line feed counter, 13 ... Data receiving flag memory, 14 ... Printing flag memory.

Claims (1)

[Claims] 1. A paper end detection sensor is arranged apart from the print head, and the last line position on which the paper can be printed after the paper end detection is detected by the paper end detection sensor is set by the number of line feed counters. In the printer, a data processing flag memory that stores information indicating that the printer is receiving data only while receiving data from a host device; and information that the printer is performing printing operation only during printing operation The timing for outputting the paper end information to the host device is connected to each of the printing operation flag memory, the paper end detection sensor, the line feed number counter, the data processing flag memory, and the printing operation flag memory. And a CPU for controlling, (a) the data processing flag before the paper end detection by the paper end detection sensor. When the paper end detection sensor detects the end of the paper when neither the information indicating that the memory is receiving data nor the information indicating that the print operation flag memory is performing the print operation is present. Means for immediately outputting the paper end information to the host device; and (b) information indicating that data is being received in the data processing flag memory and that printing is being performed in the printing operation flag memory. In the state where one of the information is present, after the paper end detection sensor detects the paper end, while the paper end reaches the final line position set by the line feed counter, it is stored in the data processing flag memory. When either the information indicating that the data is being received or the information indicating that the printing operation is in progress in the printing flag memory does not exist, the sheet is immediately printed. The end information is output to the higher-level device, and information indicating that data is being received in the data processing flag memory and the printing operation flag while the sheet end reaches the final line position set by the line feed counter. When either one of the information indicating that the printing operation is being performed remains in the memory, a unit for outputting the paper end information to the upper device after printing until reaching the last line position, A printer characterized by the above.