JPH02225067A - Page printer - Google Patents

Abstract

PURPOSE:To switch over to another printing process quickly while a printing process which is already started is still underway without the necessity to undergo troublesome procedures for resumption of the suspended process by selecting a priority for data processing to any of interfaces. CONSTITUTION:If SW 18 is set to 'priority to interface 1', a control circuit 11 receives data 1 from the first host computer 17a through an I/F circuit 15a. The control circuit 11 performs printing of data 1 in units of page while storing the received data 1 sequentially in memory 13a. If SW 18 is set to 'priority to interface 2', the control circuit 11 stops receiving data 1 via the I/F circuit 15a. The control circuit 11 suspends printing data 1 for a while, and instead receives data 2 from the second host computer 17b through an I/F circuit 15b. Then the circuit 11 performs printing data 2 while sequentially storing it in memory 13b. After completion of printing the data 2, SW 18 is reset to 'priority to interface 1', and consequently, the control circuit 11 resumes reception of data 1 through the I/F circuit 15a. Simultaneously the circuit 11 reads data 1 from memory 13a, resuming the printing process.

Description

[Detailed Description of the Invention] [Objects and Targets of the Invention] (Industrial Application Field) The present invention relates to a page printer such as a laser printer that prints page by page, and particularly relates to a page printer that prints on a page-by-page basis, such as a laser printer. Regarding page printers (prior art) Conventionally, when a page printer such as a laser printer is printing a large amount of data or graphic printing with a large amount of data, the printer does not wait until all the printing is completed. If you want to perform other printing such as urgent printing or small amount printing, the following troublesome operations are required.

In other words, it is necessary to stop the current printing process, perform another printing process, and then restart the previous process from where it left off. In other words, if the current printing is stopped at the first page, for example, the host computer must be operated to start printing from the second page.

Further, in a printer that does not have such a means for restarting printing from the middle of printing, it is necessary to restart the previous process from the beginning, that is, from the first page.

(Problems to be Solved by the Invention) As described above, conventionally, there have been problems such as when printing another character in the middle of printing, a troublesome operation is required to resume the previous printing.

The present invention has been made in view of the above points, and it is an object of the present invention to provide a page printer that can quickly perform other printing in the middle of printing without requiring troublesome operations to resume previous printing. With the goal.

[Structure of the Invention] (Means for Solving the Problems) That is, the page printer according to the present invention is configured to individually receive print data from at least two or more host computers through a plurality of interfaces and store the data in a memory. The configuration is such that printing is executed by switching the data processing priority of each of the interfaces.

(Function) According to the above configuration, simply by switching the priority of the interface, it is possible to print data by interrupting one print process while printing data from another, or to print data from two or more host computers alternately. To quickly perform other printing in the middle of printing without requiring troublesome operations.

(Embodiment) Hereinafter, a page printer according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing the circuit configuration. A control circuit 11 that controls the entire device includes a system bus 1.
2, memory 13a, 13b, engine 14, interface circuit (hereinafter referred to as I/F circuit) 15a
, 15b, and I10 boats 16 are connected, respectively.

Memories 13a and 13b are both page memories.

Among these, the memory 13a stores data 1 of the first host computer (hereinafter referred to as the first host) 17a that is received through the I/F circuit 15a.

On the other hand, the memory 13b stores data 2 from the second host computer (hereinafter referred to as second host) 17b received through the I/F circuit 15b.

The engine 14 represents a printing mechanism section of a page printer.
The 1/F circuits 15a and 15b both transmit and receive data to and from an external device, and are connected to the first host 1, respectively.
7ax receives data 1.2 from the second host 17b. The I10 boat 1B has a changeover switch (hereinafter referred to as SW).
18 signal input controls are performed. This 5W1B is a switch for switching the priority of data processing of the I/F circuits 15a and 15b.

Next, the operation of this embodiment will be explained.

For example, if 5W18 is "interface 1 priority",
The control circuit 11 is an I/F circuit 15a and a first host 17a.
Receive data 1 from. Then, the control circuit 11 prints the data 1 page by page while sequentially storing the received data 1 in the memory 13a. Here, when 5WII+ is switched to [interface 2 priority] while printing data 1, the control circuit 11
5a stops receiving data 1. Then, the control circuit 11 temporarily suspends printing of data 1 and instead prints data 1/F.
The circuit 15b receives the data 2 from the second host 17b, and while sequentially storing it in the memory 13b, the data 2 is stored in the memory 13b.
Executes printing. After printing this data 2, 5wt
5 to "interface 1 priority", control circuit 1
1 starts receiving data 1 again by the 1/F circuit 15a, and at the same time reads data 1 from the memory 13a and resumes printing.

Further, if SWlg is "interface 1.2 alternate", the control circuit 11 prints data 1.2 for each page while switching the priorities of the two I/F circuits 15ax15b on a page-by-page basis. That is, for example, if the 1/F circuit 15a receives page break instruction data, the I/F circuit 15a receives the page break instruction data.
The /F circuit f5a stops receiving data 1, the I/F circuit 15b starts receiving data 2, and data 1.2 are printed alternately on each page.

In this way, the I/F circuit 15a115
By arbitrarily switching the priority of data 1.b, it is possible to interrupt print data of one data during the printing process of the other, and by alternately switching the priority of I/F circuits 15a and 15b, each data 1.b can be printed. 2 can also be printed alternately on a page-by-page basis.

Note that in this embodiment, there are two I/F circuits 15a.

When one side of the 15b is receiving data, data reception on the other side is stopped, but in this case, a busy signal is output from the I/F circuit on the side that stopped receiving data to the host computer. If this busy signal is output for a period exceeding a predetermined period, there is a problem in that the host side considers that an abnormality has occurred (this is called a timeout). If printing is to be performed on one side such that the data reception suspension period exceeds a predetermined period, the following method may be used.

That is, either the busy signal is output intermittently to prevent a timeout period, or both I/F circuits 15a and 15b are kept in a data receiving state. However, I/F circuits 15a, 15
When setting both b to data reception mode, either receive data little by little to prevent the memory from filling up, or
Alternatively, it is necessary to take measures such as forcibly releasing data and printing when the memory becomes full to a certain extent.

Furthermore, although this embodiment has a configuration in which print data from two host computers are printed, the present invention is not limited to this.
It is also possible to print print data from more than one host computer.

Further, the present invention is not limited to page printers, but can also be applied to serial printers as long as they use cut sheets and print a large amount of data. In this case,
A configuration may be adopted in which one memory is provided for a plurality of I/F circuits, and data from each host computer is received and printed in well-defined sections (eg, one page at a time).

[Effects of the Invention] As described above, according to the present invention, by switching the data processing priorities of a plurality of interfaces, printing can be performed in the middle of printing without requiring troublesome operations to restart previous printing. This allows other printing to be executed quickly.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a circuit configuration according to an embodiment of the present invention. 11... Control circuit, 12... System bus, 13a
and 13b... memory, 14... engine, 15
a and 15b...1/F circuit (interface circuit) 1B...I10 port, 17a...first host (first host computer) 17b...
Second host (second host computer) 1B・
...SW (selector switch). Applicant's agent Patent attorney Takehiko Suzue

Claims (1)

[Scope of Claims] A plurality of interfaces that individually receive print data from at least two or more host computers; a memory that stores print data received by each of the interfaces; and a memory that stores the print data received by each of the interfaces; A page printer comprising: switching means for switching priorities; and print control means for executing printing according to the priority of data processing switched by the switching means.