JP4243831B2 - Printer and printer job data transfer method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a printer connected to a network. In particular, the present invention relates to a printer using TCP / IP which is a general-purpose network protocol.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, network-compatible printers that are connected to a LAN constructed by Ethernet (registered trademark) or the like and can be shared by a plurality of host computers are known. The host computer performs network communication with the printer according to a predetermined network protocol, and sends print job data output from the printer driver to the printer. Examples of the network protocol for the host computer to send print job data to the printer include an LPR protocol implemented on TCP / IP.
[0003]
In an environment where such a network printer is provided, a printer server is generally provided in order to efficiently use the network. The printer server performs network communication with the host computer, receives print job data from the printer server, spools the print job data once in a storage device such as a hard disk, and then sequentially sends out the print job data. As shown in FIG. 3, for example, the printer server is configured independently of the outside of the printer (hereinafter referred to as “printer server outside printer”) and the printer itself is configured (hereinafter “printer”). "Internal printer server").
[0004]
In the method using the printer server outside the printer ((a) in the figure), the print job data transmitted from the host computer by the LPR protocol is spooled to the printer server main body and then transmitted to the printer designated by the LPR protocol. Printing processing will be performed.
[0005]
On the other hand, in the method using the printer server in the printer ((b) in the figure), the print job data is spooled to the printer server body in the printer and then sent directly to the print processing circuit through the internal interface. The printing process is performed.
[0006]
[Problems to be solved by the invention]
Each time a new off-printer print server to be introduced into the network printer environment is developed, it is necessary to develop an interface between the print server main body and the LPR client.
[0007]
On the other hand, in the case of an in-printer print server, it is necessary to develop an interface between the printer server main body and the print processing circuit. For this reason, when a new high-performance engine is developed, the interface itself is accordingly developed. Also had to be developed.
[0008]
The print server is preferably realized by various protocols other than the LPR protocol on TCP / IP, but it is not realistic to be configured to support any protocol such as NetWare or AppleTalk.
[0009]
Therefore, an object of the present invention is to eliminate the trouble of developing interfaces depending on individual print servers.
[0010]
More specifically, an object of the present invention is to provide an in-printer print server that employs an LPR protocol, which is a standard network protocol, for communication between a print server main body and a print processing circuit.
[0011]
[Means for Solving the Problems]
The present invention for solving the above-mentioned problems is specified as follows.
[0012]
The gist of the present invention is a printer including a print server, wherein print job data spooled in the print server is transmitted to a print processing unit by designating a loopback address defined by IP. Printer.
[0013]
More specifically, a first receiving means for receiving print job data transmitted from a host computer according to a first protocol, a print server for spooling print job data received by the first receiving means, First transmission means for transmitting print job data spooled in the print server according to a second protocol, and second reception for receiving print job data transmitted by the first transmission means according to the second protocol Means, print processing means for generating image data based on the print job data received by the second receiving means, and printing on the print recording medium based on the image data generated by the print processing means And a printing execution means.
[0014]
Here, the first transmission means transmits the print job data using a loopback address defined by IP (Internet Protocol) known as a network protocol.
[0015]
Further, the first transmission means designates a predetermined port and transmits the print job data, and the second reception means receives at the designated predetermined port.
[0016]
Further, the predetermined port is different from a port received by the first receiving means when the first protocol and the second protocol are the same.
[0017]
Furthermore, it is preferable that the first protocol and / or the second protocol is an LPR protocol implemented on TCP / IP.
[0018]
The printer further includes conversion means for converting print job data according to the first protocol into print job data according to the second protocol.
[0019]
The invention of the apparatus is also established as a method invention. That is, the present invention relates to a method for transferring print job data in a printer having a print server, wherein the transmission means provided on the print server side for print job data spooled in the print server is defined by IP. The print job data transfer method is characterized in that a loopback address is designated and transmitted to a receiving means provided on the print processing means side.
[0020]
Furthermore, the present invention can also be realized as a recording medium that records a program that causes a printer to realize a predetermined function. More specifically, the present invention is a recording medium that records a program that causes a printer to realize a predetermined function, and the program includes a first reception function that receives print job data transmitted from a host computer. A spool function for spooling print job data received by the first reception function in a predetermined storage device; a first transmission function for transmitting print job data spooled in the storage device according to a predetermined protocol; A second reception function for receiving print job data transmitted by the first transmission function according to the predetermined protocol, and generation for generating image data based on the print job data received by the second reception function Function and the image data generated by the generation function A control function of controlling so as to perform printing on the recording medium to the print engine, which is a recording medium for recording a program characterized by comprising a.
[0021]
Here, the recording medium includes, for example, a memory such as a RAM and a ROM in addition to a hard disk (HD), a DVD-RAM, a flexible disk (FD), and a CD-ROM. The printer includes, for example, a so-called microcomputer in which a so-called central processing unit such as a CPU or MPU performs predetermined processing by interpreting a program.
[0022]
The program may be realized including a function for calling a function realized by a basic program such as an operating system.
[0023]
Furthermore, the present invention may be configured as a print system including the printer and a computer.
[0024]
In this specification, the term “means” does not simply mean a physical means, but also includes a case where the functions of the means are realized by software. Further, the function of one means may be realized by two or more physical means, or the functions of two or more means may be realized by one physical means.
[0025]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the present invention will be described with reference to the drawings.
[0026]
FIG. 1 is a diagram for explaining an overview of a print system according to the present embodiment. As shown in the figure, the host computer 1 and the printer 2 are connected via a predetermined network N to constitute a printing system. In the figure, a representative one of a plurality of host computers 1 and printers 2 connected to the network N is shown. The network N is realized, for example, according to the Ethernet standard. The host computer 1 and the printer 2 are equipped with a communication interface 11 for realizing a network service according to TCP / IP which is a general-purpose network communication protocol. That is, the communication interface 11 of the present embodiment realizes a communication service positioned as a lower layer protocol in the network protocol layer model. An IP address, which is a unique network address, is assigned to each of the host computer 1 and the printer 2 that are grasped as nodes on the network N. The communication interface 11 includes various hardware and various software for realizing a TCP / IP service. The communication interface 11 has an I / O port (hereinafter referred to as “port”) to which a unique number (for example, 0 to 65535) is assigned, and provides a communication service via a port specified in packet data.
[0027]
The application program 12 is, for example, a word processor for creating / editing a document, a graphic editor for creating / editing a figure, and the like. Now, when a print command is given from the user via the user interface, the application program 12 calls a printer driver (not shown). The printer driver receives the application data to be printed from the application program 12, converts the application data into print job data to be interpreted by the printer 2, and outputs the print job data to the LPR client 13A. The LPR client 13A transmits the print job data sent from the printer driver to the printer 2 designated as the print output destination according to a predetermined network communication protocol. That is, when the host computer 1 tries to cause a specific printer 2 to perform printing, the IP address assigned to the printer 2 is designated and transmitted. In this case, the LPR client 13A also specifies a specific port of the other party. When communicating with the LPR server 14A, the number 515 is designated as the destination port. The LPR server 14A receives print job data from the LPR client 13A and outputs it to the print server main body 15.
[0028]
The print server body 15 typically includes a storage device such as a hard disk device for spooling input print job data. The print server main body 15 has a function of managing job requests based on input of one or more print job data and sequentially sending them to the print processing circuit 16 one by one. The print server body 15 can receive a plurality of print job data (print requests) from the host computer 1 and process the print requests sequentially regardless of the print processing status. The print job data is sent from the print server main body 15 to the print processing circuit 16 via the LPR client 13B and the LPR server 14B. The LPR client 13B and the LPR server 14B are also mounted on TCP / IP. Therefore, the LPR client 13B performs communication by designating a specific port and a specific IP address. Here, the IP address designated as the transmission destination by the LPR client 13B is a loopback address. The specific port is, for example, 8515.
[0029]
The print processing circuit 16 interprets the print job data received from the LPR server 13B, generates image data, and supplies it to the print engine 17. The print processing circuit 16 typically includes an interpretation program for interpreting print job data, a ROM that records font data, a processor that executes the interpretation program and expands the print job data into image data, and a processor work It is composed of a RAM that stores image data used as an area and developed. When the image processing with a predetermined bandwidth is developed, the print processing circuit 16 outputs a print request signal to the print engine 17, and outputs the image data to the print engine 17 in accordance with a synchronization signal sent from the print engine 17.
[0030]
The print engine 17 includes, for example, a paper feed mechanism, a print head, and the like, and performs printing on a print recording medium such as paper. As the print engine 38, a printer corresponding to the type of printer such as a laser printer or a serial printer can be used.
[0031]
The LPR clients 13A and 13B and the LPR servers 14A and 14B described above are programs for realizing a communication service positioned as an upper layer protocol in the network layer model. The LPR clients 13A and 13B and the LPR servers 14A and 14B are executed as so-called daemon programs, and upon receiving a predetermined event, perform communication processing according to a predetermined network communication protocol.
[0032]
The LPR client 13 designates the IP address and port of the transmission destination, converts the data to be transmitted physically and logically, and transmits the lower level communication service means (communication interface 11 in this embodiment). Send to network N. When the communication interface 11 receives the packet data addressed to itself flowing on the network N, the communication interface 11 physically and logically converts the data to the port specified by the received data, so that the upper communication service Give it to the means. The LPR server 14 is set to perform communication through a designated port. In the LPR server 14A in the present embodiment, for example, a port 515 is designated. Accordingly, the communication interface 11 delivers the data to the LPR server 14A when the data No. 515 is designated.
[0033]
As described above, the LPR client 13B designates a loopback address as an IP address and sends out print job data. The loopback address is an address used for transmission to itself. In IPv4, the loopback address is expressed as “127.0.0.1”, and in the IPv4 IPv4 compatible format, it is expressed as “0: 0: 0: 0: 0: 0: 127.0.0.1”. The Further, the LPR client 13B is set to designate, for example, 8515 as the counterpart port. The LPR server 14B is set to perform communication via a port designated by the LPR client 13B (that is, number 8515 in this example). Accordingly, when the communication interface 11 receives data in which the number 8515 is designated, the communication interface 11 passes the data to the LPR server 14B.
[0034]
Next, an operation example of the print system configured as described above will be described. Here, it is assumed that the host computer 1 is assigned an IP address “161.141.22.5” and the printer 2 is assigned “163.141.22.5”. Further, it is assumed that the port number 515 is assigned to the LPR server 14A and the port number 8515 is assigned to the LPR server 14B.
[0035]
Assume that the host computer 1 transmits a print request (print job data) to the printer 2. The host computer 1 designates the destination port number 515 of the TCP header of the data to be transmitted and designates the destination IP address “163.141.22.5” of the IP header and sends it out. Note that, as the transmission source port number, an arbitrary value other than the reserved port number (1024 or more) is typically dynamically assigned. FIG. 2A shows the structure of data transmitted from the host computer 1 to the printer 2. When the printer 2 receives a print request from the host computer 1 via the network environment, the printer 2 once spools the request to the print server main body 15 and sequentially sends it to the print processing circuit 16 according to the print processing status. At this time, a loopback address “127.0.0.1” is designated as the destination IP address of the IP header, and 8515 is designated as the destination port number. FIG. 2B is a diagram illustrating a structure of data transmitted from the print server main body 15 to the print processing circuit 16. As a result, data transmitted from the print server main body 15 to the print processing circuit 16 is looped back in the IP layer and transferred from the port number 8515 to the print processing circuit 16 via the LPR server 14B.
[0036]
As described above, according to the present embodiment, data is transmitted and received according to the LPR client / server based on the standard network technology TCP / IP, so that the print server main body reaches the print processing circuit. It is no longer necessary to develop the interface part until now, and the development cost can be kept low. For example, even when a LAN is constructed with a network protocol other than TCP / IP, it is sufficient to adopt a standard LPR service program for the interface from the print server main body to the print processing circuit. In this case, conversion from various network protocols to the LPR protocol may be executed by a module in the print server. In other words, it is not necessary to newly develop an interface corresponding to various network protocols, and an n-to-LPR conversion program may be provided for n protocols.
[0037]
In the above embodiment, a protocol (first protocol) for transmitting print job data from the host computer 1 to the print server body 15 and a protocol (second protocol) for transmitting print job data from the print server body 15 to the print processing circuit 16 are described. However, it is not necessary to be particularly concerned with this.
[0038]
For example, as shown in FIG. 3, the second client 13A (corresponding to the LPR client in FIG. 1) of the host computer 1 is connected to the second server 14B (on the LPR server in FIG. 1) provided on the print processing circuit 16 side. The print job data may be transmitted directly.
[0039]
The said embodiment is an illustration for demonstrating this invention, and is not the meaning which limits this invention only to this embodiment. The present invention can be implemented in various forms without departing from the gist thereof. For example, although the operation of the function realizing unit has been described sequentially, it is not particularly limited to this. Therefore, as long as no contradiction occurs in the operation, the processing order may be changed or the operations may be performed in parallel. In the present embodiment, the description is based on IPv4. However, IPv6 may be used.
[0040]
【The invention's effect】
According to the present invention, it is not necessary to develop an interface for each printer model, and the development cost can be kept extremely low.
[Brief description of the drawings]
FIG. 1 is a diagram for explaining a configuration of a print system according to the present invention.
FIG. 2 is a diagram showing a structure of transmission data.
FIG. 3 is a diagram for explaining the configuration of another print system according to the present invention.
FIG. 4 is a diagram illustrating a configuration of a conventional print system.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 11 ... Communication interface 12 ... Application program 13 ... LPR client 14 ... LPR server 15 ... Print server main body 16 ... Print processing circuit 17 ... Print engine

Claims (2)

First receiving means for receiving print job data transmitted from a host computer according to the LPR protocol on TCP / IP;
A print server for spooling print job data received by the first receiving means, and a print job data spooled in the print server using a loopback address on TCP / IP and specifying a predetermined port number And a first transmission means for transmitting
Second receiving means for receiving print job data transmitted by the first transmitting means;
Print processing means for generating image data based on print job data received by the second receiving means;
Print execution means for executing printing on a print recording medium based on the image data generated by the print processing means;
A printer comprising: A recording medium on which a program for causing a printer to realize a predetermined function is recorded ,
The program is
A first reception function for receiving print job data transmitted from a host computer;
A spool function for spooling print job data received by the first reception function in a predetermined storage device;
A first transmission function for transmitting print job data spooled in the storage device according to a predetermined protocol;
A second reception function for receiving the print job data transmitted by the first transmission function according to the predetermined protocol;
A generation function for generating image data based on the print job data received by the second reception function;
A control function for controlling the print engine to perform printing on the print recording medium based on the image data generated by the generation function;
The recording medium which recorded the program characterized by having provided.

Images