JPH06297815A - Multi-port printer - Google Patents

Abstract

PURPOSE:To efficiently use a printer without the exclusive use of the printer by a specific host device. CONSTITUTION:A title multi-port printer comprises an interface 3 receiving printing data and the number of printing pages that are respectively transmitted from a plurality of host devices 1, 2; a memory 4 storing the printing data; a printing part 5 printing the printing data; and registers 10, 11 respectively corresponding to the two or more host devices 1, 2 and subtracting the number of pages printed by the printing part 5 from the number of printing pages. Furthermore, it comprises a comparison part 12 discriminating a relation of magnitude between the values of the registers 10, 11; a control part 6 controlling the printing part 5 so as to print printing data from a specific host device selected out of the two or more host devices 1, 2 based on the discriminated result of the comparison part 12; and a time allocation part 13 allowing a host device corresponding to a register of a specific value compared with the value of the register corresponding to the specific host device to transmit printing data with the priority under control after the printing part 5 is occupied by the specific host device for a predetermined time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-port printer, and more particularly to a multi-port printer that receives print data from a plurality of host devices and prints it.

[0002]

2. Description of the Related Art FIG. 4 is a block diagram showing an example of a conventional multi-port printer. Referring to FIG. 4, the conventional multi-port printer 14 includes a host device 1 and 2 for transmitting print data, an interface 3 for receiving the print data, a memory 4 for temporarily storing the print data, and a printout for the print data. Printing unit 5 that prints out data
And a control unit 6 for controlling each part.

Now, it is assumed that the host device 1 is transmitting print data. At that time, the higher-level device 2 tries to transmit the print data, but since the busy signal is raised on the signal line 9, the higher-level device 2 cannot transmit the print data, and must wait until the high-level device 1 finishes transmitting the print data.

[0004]

In this conventional multi-port printer, when print data is being transmitted from a certain higher-level device, other higher-level devices cannot transmit until the print data transmission of this higher-level device is completed. It interferes with the processing of the host device.

[0005]

A multi-port printer of the present invention comprises a receiving means for receiving print data and the number of print pages respectively transmitted from a plurality of host devices, a storage means for storing the print data, A printing unit that prints the print data, a register group that temporarily stores the number of printed pages and that subtracts the number of pages that the printing unit has finished printing from the number of printed pages, and a register group that corresponds to each of the plurality of upper devices, and these Comparing means for discriminating the magnitude relationship of the values of the register group, and control for controlling the printing means to print the print data from a specific upper device among the plurality of upper devices based on the discrimination of the comparing device. And means.

Further, the multi-port printer of the present invention corresponds to a register having a specific value which is compared with a value of a register corresponding to the specific upper device when the printing means is occupied by the specific upper device for a predetermined time. A time allocation means is provided for controlling the higher-level device to preferentially transmit print data.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings. Referring to FIG. 1 which is a block diagram of a first embodiment of the present invention, in a multi-port printer 15 of this embodiment, an interface 3 is a printing device which transmits signals from host devices 1 and 2 via signal lines 8 and 9, respectively. Receives data and the number of pages to print. The memory 4 stores this print data. The printing unit 5 prints print data. The first register 10 and the second register 11 respectively corresponding to the higher-level devices 1 and 2 temporarily store the number of printed pages, and subtract the number of pages printed by the printing unit 5 from the number of printed pages. The comparison unit 12 determines the magnitude relationship between the values of the first register 10 and the second register 11. The control unit 6 controls the printing unit 5 to print the print data from a specific upper device of the upper devices 1 and 2 based on the determination of the comparison unit 12.

FIG. 2 is a flow chart for explaining the operation of this embodiment. The operation of this embodiment will be described with reference to FIG. 2 together with FIG. It is assumed that a numerical value 5 is transmitted from the upper level device 1 as the number of print pages of the print request. The transmitted number 5, which is the number of print pages, is stored in the first register 10 via the interface 3 (S2). At this time, it is assumed that the host device 2 is not operating. If the initial values of the registers 10 and 11 are set to infinity (S1), the first register 10
Is 5, and the content of the second register 11 is infinite, the comparison unit 12 uses the registers 10 and 11
Are compared (S3), and since the content of the first register 10 is small, the printing unit 5 sets the print data from the host device 1 to 1
The page is printed (S4). Each time the printing unit 5 finishes printing one page, the control unit 6 sends a signal via the signal line 7 so as to subtract the numerical value 1 from the register 10 (S5). In this way, when the content of the first register 10 becomes the value 3, it is assumed that the numerical value 2 is stored in the second register 11 as the number of print pages of the print request from the upper level device 2 (S2). The comparing unit 12 compares the contents of the registers 10 and 11 (S3) and the contents of the second register 11 are small, so the printing unit 5 prints the print data from the higher-level device 2 (S3).
4). If the number of pages to be printed in the print request from the higher-level device 2 is 3 or more, the printing unit 5 subsequently prints the print data from the higher-level device 1. In this way, the print data of the higher-level device having a smaller number of print pages is printed with priority, and after the printing is completed, the content of the register is set to infinity (S7), so that the print data of the other higher-level device is printed again. To be executed.

Next, referring to FIG. 3 which is a block diagram showing a second embodiment of the present invention, in the multi-port printer 16 of this embodiment, the interface 3, the memory 4, the printing section 5, the upper devices 1 and 2 are provided. The functions of the corresponding first register 10 and second register 11, the comparison unit 12, and the control unit 6 are the same as those in the above-described first embodiment. When the printing unit 5 is occupied by a specific upper device for a predetermined time, the time allocation unit 13 preferentially prints the print data by the upper device corresponding to the register of the specific value compared with the value of the register corresponding to the specific upper device. Control to send.

FIG. 4 is a flow chart for explaining the operation of this embodiment. The operation of this embodiment will be described with reference to FIG. 4 together with FIG. Similar to the first embodiment described above, first, the printing unit 5 prints the print data from the higher-level device 1 (S1 to S
7). When the printing of the print data from the higher-level device 1 is not completed after the lapse of the specific time (S8), the time allocating unit 13 operates to invalidate the control of the comparing unit 12 (S9), and the higher-level device currently transmitting the print data. 1st register 10 corresponding to 1
The priority is given to the higher-level device 2 corresponding to the second register 11 having the next largest value (S10), one page of print data from the higher-level device 2 is printed, and the value of the second register 11 is set to one. Subtract (S11). In this case, if the register having the above value does not exist (S10), the print data of the host device corresponding to the register having the minimum value is printed (S12). When printing is completed within the specified time (S1
Only in 3), the control of the comparison unit 12 is enabled (S15),
Infinity is set in the register corresponding to the completed upper device (S16), and the register values are compared (S3).

In the first and second embodiments described above,
The number of host devices and registers is two, respectively,
A higher number is also acceptable. Further, although the comparison unit 12 selects a register having a small value, it may also select a value according to a predetermined rule.

[0012]

As described above, according to the present invention,
The print data and the number of print pages transmitted from each of the plurality of host devices are received, the number of print pages is temporarily stored, and the magnitude relationship of the value obtained by subtracting the number of pages that have been printed from this number of print pages is determined. By printing the print data from a specific higher-level device among a plurality of higher-level devices based on the determination, the print data with a smaller number of print pages when a print request is made is printed with priority, and thus the number of print pages is larger. The printer can be efficiently used without being monopolized by the upper device.

Further, when a specific upper-level device is occupied for a predetermined time, the upper-level device corresponding to the register having the specific value compared with the value of the register corresponding to the specific higher-level device can preferentially transmit the print data. By controlling the print data, which takes time even if the number of print pages is small, the printer can be used efficiently by postponing the print data.

[Brief description of drawings]

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

FIG. 2 is a flow chart showing an example of an operation in the same embodiment.

FIG. 3 is a block diagram showing a configuration of a second exemplary embodiment of the present invention.

FIG. 4 is a flowchart showing an example of an operation in the embodiment.

FIG. 5 is a block diagram showing a configuration of a conventional example.

[Explanation of symbols]

 1, 2 Host device 3 Interface 4 Memory 5 Printing unit 6 Control unit 7, 8, 9 Signal line 10 First register 11 Second register 12 Comparison unit 13 Time allocation unit 14, 15, 16 Printer

Claims (2)

[Claims] 1. A receiving unit for receiving print data and the number of pages to be printed, which are respectively transmitted from a plurality of upper devices, a storage unit for storing the print data, a printing unit for printing the print data, and the printing. A register group for temporarily storing the number of pages and subtracting the number of pages printed by the printing unit from the number of printed pages and a register unit corresponding to each of the plurality of higher-level devices and a comparing unit for discriminating the magnitude relationship between the values of these register groups. And a control unit that controls the printing unit to print the print data from a specific upper-level device among the plurality of higher-level devices based on the determination of the comparison unit. . 2. When the printing unit is occupied by the specific upper device for a predetermined time, the upper device corresponding to the register having a specific value compared with the value of the register corresponding to the specific upper device is given priority to print data. 2. The multi-port printer according to claim 1, further comprising a time allocating means for controlling so that the printer can be transmitted.