BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to an image forming apparatus, and a print system including an image forming apparatus, allowing for network connections simplified to set up. 
         [0003]    2. Description of Related Arts 
         [0004]    Japanese Patent Application Laid-Open Publication No. 2006-319644 has disclosed an image forming apparatus provided with a plurality of interfaces for communications with networked equipments. For network connections to be made of such an image forming apparatus, respective interfaces need to have their addresses individually set up. 
         [0005]    Some types of image forming apparatuses have no parts to function as an RIP (raster image processor) for rasterizing a page description language such as PostScript. For connection of such a type of image forming apparatus to a LAN to thereby print a data described in a page description language, there should be provision of an RIP unit for rasterizing the data, and connection of the RIP unit to the image forming apparatus. Further, there are needs of having the data in page description language input via the LAN to the RIP unit, having a bit map data developed at the RIP unit and output to the image forming apparatus, and having the image forming apparatus make a print in accordance with the bit map data. 
         [0006]    Accordingly, such a type of image forming apparatus needs to have an interface for direct printable data to be input thereto from a PC (personal computer) via a LAN, and another interface for raster data to be input thereto from the PC via an RIP unit. The RIP unit needs to have an interface for data in page description language to be input thereto from the PC via the LAN, and another interface for raster data to be output therefrom to the image forming apparatus. 
       SUMMARY OF THE INVENTION 
       [0007]    There is a protocol used for connection between the RIP unit and the image forming apparatus. For that protocol to be identical to a protocol for the LAN interconnecting the PC and the image forming apparatus, the interface for connection of this image forming apparatus with the RIP unit and the interface for connection of the RIP unit with the image forming apparatus should have their addresses each respectively different from address of interfaces the PC has for connection with the LAN. Further, each of those addresses should be different from an address of the interface for connection of the image forming apparatus with the LAN and an address of the interface for connection of the RIP unit with the LAN. In addition, for communications between the RIP unit and the image forming apparatus, the interfaces paired in between should each have an address of the opponent set therein. As a result, there has been a significant burden on a network manager serving to connect a combination of an image forming apparatus and an RIP unit to associated LANs. 
         [0008]    It is an object of the present invention to provide an image forming apparatus, and a print system including an image forming apparatus, having a plurality of interfaces for connections through networks to an image processor, allowing for network connections simplified to set up. 
         [0009]    To achieve the object described, according to a first aspect of the present invention, an image forming apparatus is connected to a plurality of networks including a network connected with an image processor and adapted for storage of a plurality of address sets each composed of a first kind address of the image processor and a first kind address of the image forming apparatus, the image forming apparatus comprising a storer configured to store in memory a plurality of address sets each composed of a first kind address of the image forming apparatus and a first kind address of the image processor, and a communication controller configured to employ the plurality of address sets stored in memory of the storer, for a sequence of trials of connection with the image processor to determine a connectable address set to use for communications with the image processor. 
         [0010]    To achieve the object described, according to a second aspect of the present invention, a print system includes a combination of an image processor and an image former connected therewith through a network, the image former connected to a plurality of networks including the network, wherein the image processor comprises a storer configured to store in memory a plurality of address sets each composed of a first kind address of the image processor and a first kind address of the image former, and a setup acceptor configured to accept a selection of any address set of the plurality of address sets, and the image former comprises a storer configured to store in memory a plurality of address sets each composed of a first kind address of the image former and a first kind address of the image processor, and a communication controller configured to employ the plurality of address sets stored in memory of the storer of the image former, for a sequence of trials of connection with the image processor to determine a connectable address set to use for communications with the image processor. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0011]      FIG. 1  is a block diagram showing configuration of a networked print system according to an embodiment of the present invention. 
           [0012]      FIG. 2  is a block diagram showing functional configuration of a combination of a printer and an RIP unit according to a first example of the embodiment. 
           [0013]      FIG. 3  is a table listing examples of address sets stored at the printer end, and address sets stored at the RIP unit end. 
           [0014]      FIG. 4  is an illustration of a setup acceptance frame provided by an IP setup acceptor of the printer. 
           [0015]      FIG. 5  is an illustration of a setup acceptance frame provided by an IP setup acceptor of the RIP unit. 
           [0016]      FIG. 6  is a block diagram showing functional configuration of a combination of a printer and an RIP unit according to a second example of the embodiment. 
           [0017]      FIG. 7  is part of a flowchart of control actions in an automatic network setup process at the printer. 
           [0018]      FIG. 8  is the rest of the flowchart. 
       
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
       [0019]    There will be described modes of embodiment of the present invention, with reference to drawings.  FIG. 1  is a block diagram showing configuration of a networked print system according an embodiment of the present invention. As illustrated in the figure, there is a networked print system  100 , which is configured with a printer  10  working as an image former and an RIP unit  20  working as an image processor, each respectively connected with a plurality of PCs  30  (i.e. a PC  30   a , a PC  30   b , . . . ) through a first network  40 , while the RIP unit  20  is connected through a second network  41  to the printer  10 . In typical applications, the first and second networks  40  and  41  may well be LANs composed of IP networks. The network  40  as well as the network  41  may be a LAN, WAN, or Internet composed of a TCP/IP network. In this embodiment, they are each made up as a LAN of TCP/IP network. In the IP network, each interface connected to the LAN is identified by an IP address. Accordingly, interfaces of associated equipments need to have different IP addresses. 
         [0020]    The printer  10  is configured to make a print in accordance with a print data input thereto, the print data being formatted in a prescribed manner. In this respect, the printer  10  is not adapted to rasterize a page description language such as PostScript. The printer  10  has a LAN port C and a LAN port X as network interfaces. The LAN port C is a LAN port for connection to the first network  40 , and has an IP address preset by a network manager. The LAN port X is a LAN port for connection to the RIP unit  20  through the second network  41 , and will be given an IP address set up in a later-described manner. 
         [0021]    The RIP unit  20  is an image processor adapted to rasterize a page description language such as PostScript, and has a LAN port D and a LAN port Y as network interfaces. The LAN port D is a LAN port for connection to the first network  40 , and has an IP address preset by the network manager. The LAN port Y is a LAN port for connection to the printer  10  through the second network  41 , and will be given an IP address set up in a later-described manner. 
         [0022]    Each PC  30  has a LAN port as a network interface for connection to the first network  40 , with an IP addresses preset by the network manager. Any PC  30  may be connected to the first network  40 , with an IP address then determined dynamically. 
         [0023]    In the networked print system  100 , any PC, e.g., the PC  30   a , is adapted to provide a normal print data that the printer  10  can interpret to make a print. This print data is output through the first network  40  to the LAN port C of printer  10 . The printer  10  is adapted to make a print based on thus input data. 
         [0024]    Further, each PC  30  is adapted to provide a print data described in a page description language such as PostScript that the printer  10  is unable to interpret to make a print. This print data is output through the first network  40  to the LAN port D of RIP unit  20 . At the RIP unit  20 , the print data in page description language is rasterized for conversion into a bit map data, which is output from the LAN port Y of RIP unit  20  to the LAN port X of printer  10 . The printer  10  is adapted to make a print based on thus input data. 
         [0025]    There will be described how to set up an IP address of LAN port X of printer  10 , and an IP address of LAN port Y of RIP unit  20 . 
       First Embodiment Example 
       [0026]      FIG. 2  is a block diagram showing functional configuration of a combination of a printer  10  and an RIP unit  20  according to a first embodiment example. As illustrated in the figure, the printer  10  includes a print processor  110  and a network processor  120 . The print processor  110  is configured to implement a print process in accordance with a bit map data or a print data of a prescribed format. 
         [0027]    The network processor  120  is configured to implement a set of network processes for communications through a LAN port C that is an interface to a first network  40 , and a LAN port X that is an interface to a second network  41 . In this embodiment example, the process set includes a process of setting up an IP address of the LAN port X. Hence, the network processor  120  includes an IP setup acceptor  121 , and an address set storer  122 . The IP setup acceptor  121  is configured to accept from network manager, through an operation panel (not shown) of the printer  10 , a selection of an arbitrary one of address sets each composed of an IP address of the LAN port X and an IP address of a LAN port Y of the RIP unit  20  being a destination of communication. The address set storer  122  is configured to store a set of such the address sets in a nonvolatile memory. 
         [0028]    The RIP unit  20  includes an RIP  210  as software, and a network processor  220 . The RIP  210  is configured to implement a process of rasterizing a print data in page description language for conversion into a bit map data. 
         [0029]    The network processor  220  is configured to implement a set of network processes for communications through a LAN port D that is an interface to the first network  40 , and the LAN port Y that is an interface to the second network  41 . In this embodiment example, the process set includes a process of setting up an IP address of the LAN port Y. Hence, the network processor  220  includes an IP setup acceptor  221 , and an address set storer  222 . The IP setup acceptor  221  is configured to accept from network manager, through an operation panel (not shown) of the RIP unit  20  or any locally connected equipment else, a selection of an arbitrary one of address sets each composed of an IP address of the LAN port Y and an IP address of the LAN port X being a destination of communication. The address set storer  222  is configured to store a set of such the address sets in a nonvolatile memory. This set of address sets is paired to that set of address sets stored in memory by the address set storer  122  at the network processor  120  of printer  10 . 
         [0030]      FIG. 3  illustrates an exemplary listing of address sets stored at the end of the printer  10 , and address sets stored at the end of the RIP unit  20 . In this table, there are three groups of address sets referred to as “setup  1 ”, “setup  2 ”, and “setup  3 ”. 
         [0031]    The group “setup  1 ” has set up, at the printer  10  end, an address set consisting of: an IP address P 1  (of the LAN port X) of its own; and an IP address R 1  of the LAN port Y of RIP unit  20  being a destination of communication. On the other hand, at the RIP unit  20  end, it has set up an address set consisting of: the IP address R 1  (of the LAN port Y) of its own; and the IP address P 1  of the LAN port X of printer  10  being a destination of communication. That is, both printer  10  and RIP unit  20  have a set of address sets “setup  1 ” employed for mutual recognition in between, allowing for an established interconnection to make communications as necessary It is then assumed that all LAN ports connected to the LAN  40  have IP addresses set up to be different from P 1  and R 1 . 
         [0032]    The group “setup  2 ” has set up, at the printer  10  end, an address set consisting of: an IP address P 2  (of the LAN port X) of its own; and an IP address R 2  of the LAN port Y of RIP unit  20  being a destination of communication. On the other hand, at the RIP unit  20  end, it has set up an address set consisting of: the IP address R 2  (of the LAN port Y) of its own; and the IP address P 2  of the LAN port X of printer  10  being a destination of communication. That is, both printer  10  and RIP unit  20  have a set of address sets “setup  2 ” employed for mutual recognition in between, allowing for an established interconnection to make communications as necessary. It is then assumed that all LAN ports connected to the LAN  40  have IF addresses set up to be different from P 2  and R 2 . 
         [0033]    The group “setup  3 ” has set up, at the printer  10  end, an address set consisting of: an IP address P 3  (of the LAN port X) of its own; and an IP address R 3  of the LAN port Y of RIP unit  20  being a destination of communication. On the other hand, at the RIP unit  20  end, it has set up an address set consisting of: the IP address R 3  (of the LAN port Y) of its own; and the IP address P 3  of the LAN port X of printer  10  being a destination of communication. That is, both printer  10  and RIP unit  20  have a set of address sets “setup  3 ” employed for mutual recognition in between, allowing for an established interconnection to make communications as necessary. It is then assumed that all the other LAN ports connected to the LAN  40  have IP addresses set up to be different from P 3  and R 3 . 
         [0034]    It therefore is possible for a network manager to have an address set corresponding to an address set having been set up at the printer  10 , set up at the RIP unit  20 , allowing for an established interconnection between the printer  10  and the RIP unit  20 . More specifically, it is possible to make a combination of a first selection to select e.g. “setup  1 ” on a setup acceptance frame illustrated in  FIG. 4  as a frame provided by the IP setup acceptor  121  of the printer  10 , and a second selection to select “setup  1 ” on a setup acceptance frame illustrated in  FIG. 5  as a frame provided by the IP setup acceptor  221  of the RIP unit  20 . 
         [0035]    Preferably, as in  FIG. 3 , the addresses P 1  and R 1  to be designated by selection of “setup  1 ” should each be an IP address within a range of private IP addresses (192.168.0.0 to 192.168.255.255) in the Class C (192.0.0.0 to 223.255.255.255). For selection of “setup  2 ”, the addresses P 2  and R 2  to be designated should each be an IP address within a range of private IP addresses (172.16.0.0 to 172.31.255.255) in the Class B (128.0.0.0 to 191.255.255.255). Further, for selection of “setup  3 ”, the addresses P 3  and R 3  to be designated should each be an IP address within a range of private IP addresses (10.0.0.0˜10.255.255.255) in the Class A (0.0.0.0˜127.255.255.255). It is noted that network managers may designate addresses of any address set not simply by use of IP addresses of a Class as described, but also by addresses (e.g. subnet addresses, default gateway addresses, or such) taking a subnet mask, default gateway, or such into account, as necessary. 
         [0036]    For setup of any address set, selecting a pair of addresses of a Class provides an ensured reduction of address duplication. For instance, for a network manager who has the first network  40  as a Class C under own management, it is possible to select one of “setup  2 ” and “setup  3 ” for interconnection between the printer  10  and the RIP unit  20  in the second network  41 , with a reduced probability of duplication of an IP address set up at any LAN port else in the first network  40  in which PCs and the like have IP addresses of the Class C assigned thereto. Likewise, for a network manager who has the first network  40  as a Class B under own management, it is possible to select one of “setup  1 ” and “setup  3 ” for interconnection between the printer  10  and the RIP unit  20  in the second network  41 , with a reduced probability of duplication of an IP address set up at any LAN port else in the first network  40  in which PCs and the like have IP addresses of the Class B assigned thereto. 
         [0037]    Therefore, according to the first embodiment example, it is possible for a network manager to make up easily a network connection between printer  10 , connected to a plurality of networks (first and second networks  40  and  41 ), and RIP unit  20  by simple selection of paired address sets as set up at the printer  10  and the RIP unit  20 . 
       Second Embodiment Example 
       [0038]      FIG. 6  is a block diagram showing functional configuration of a combination of a printer  10  and an RIP unit  20  according to a second embodiment example. Description of overlapping elements between the first and second embodiment examples will be simplified. 
         [0039]    As illustrated in the figure, the printer  10  includes a print processor  110  and a network processor  130 . The print processor  110  is configured to implement a print process in accordance with a bit map data or a print data of a prescribed format. 
         [0040]    The network processor  130  is configured to implement a set of network processes for communications through a LAN port C that is an interface to a first network  40 , and a LAN port X that is an interface to a second network  41 . In this embodiment example, the process set includes a process of automatically setting up an IP address of the LAN port X. Hence, the network processor  130  includes an automatic IP setter  131 . 
         [0041]    The automatic IP setter  131  is configured to automatically set up an address set employable at the printer  10 , in correspondence to an address set as set up at the RIP unit  20 . Further, the automatic IP setter  131  is adapted, when the printer  10  is powered on after a connection once made with the RIP unit  20 , to automatically start up the RIP unit  20  in concert therewith. For the automatic startup of RIP unit  20  in concert with a startup of printer  10 , there is employed an existing technique WOL (Wake On LAN). The WOL outputs a WOL signal containing a MAC (media access control) address of networked target equipment, to thereby make an automatic startup of the target equipment. 
         [0042]    Hence, the automatic IP setter  131  includes a connection setup storer  132 , an IP setup storer  133 , a MAC address storer  134 , and an address set storer  135 . Each storer may be provided with a nonvolatile memory. 
         [0043]    The address set storer  135  is similar to the address set storer  122  in the first embodiment example. The connection setup storer  132  is configured to store in memory a piece of information on whether the RIP unit  20  is connected, that has an initial value “unconnected”. This connection setup will be updated to “connected” by the automatic IP setter  131 , to be kept as it is, when and even once the connection with the RIP unit  20  is established in a later-described manner. 
         [0044]    The IP setup storer  133  is configured to store in memory an address set employed in a previous connection with the RIP unit  20 . The MAC address storer  134  is configured to store in memory a MAC address acquired from the RIP unit  20  upon an established connection therewith. 
         [0045]    The RIP unit  20  includes an RIP  210  as software, a network processor  220 , and a WOL processor  230 . The network processor  220  as well as the RIP  210  is similar to that of the first embodiment example. That is, the network processor  220  includes an IP setup acceptor  221  and an address set storer  222 . 
         [0046]    The WOL processor  230  is adapted to implement, while the RIP unit  20  is powered off, a process of receiving a WOL signal containing own MAC address, responding thereto by making an automatic startup of the RIP unit  20 . The WOL processor  230  has a known configuration. 
         [0047]    Description is now made of an automatic network setup process at the printer  10  in the second embodiment example, with reference to a flowchart shown in  FIG. 7  and  FIG. 8 . It is assumed that, at the RIP unit  20 , there has been any setup selected by network manager through the setup frame shown in  FIG. 5  or such, so there is an established address set. The selection by network manager is assumed to have been one of “setup  1 ”, “setup  2 ”, and “setup  3 ” in conformity with criteria referred to in the first embodiment example. It is noted that the RIP unit  20  should have manually powered on for an initial connection thereof. 
         [0048]    After a startup of the printer  10 , the control flow goes to a step S 101 , where the automatic IP setter  131  refers to the connection setup storer  132 , checking for a setup of connection with the RIP unit  20  to be “connected”. 
         [0049]    Unless the connection setup is “connected” (No at the step S 101 ), that is, if the RIP unit  20  has never been connected, the control flow goes to a step S 102 , to make a trial of connection with the RIP unit  20  using an address set of “setup  1 ” as a first IP address setup. 
         [0050]    As a result, if the connection is failed (No at a step S 103 ), the flow goes to a step S 108  to determine whether or not a preset time interval has elapsed. Unless the time interval has elapsed (No at the step S 108 ), the flow goes to a step S 110 , to make a trial of connection with the RIP unit  20  using an address set of “setup  2 ” as a second IP address setup. 
         [0051]    Such trials of connection are sequentially repeated, in order of address sets stored by the address set storer  135 . If the preset time interval has elapsed (Yes at the step S 108 ), the flow goes to a step S 109 , where the printer  10  works, assuming an unconnected state of the RIP unit  20 . It is noted that the connection trials are made in order of “setup  1 ”, “setup  2 ”, “setup  3 ”, “setup  1 ”, “setup  2 ”, . . . . 
         [0052]    On the other hand, in success of connection with the RIP unit  20  using some address set (Yes at the step S 103 ), the flow goes to a step S 104  for acquisition of a setup of MAC address from the RIP unit  20 . This MAC address is to be used every subsequent startup of printer  10 , to start up the RIP unit  20  in conceit. Then, at a step S 105 , the address set used in successful connection is stored in memory by the IP setup storer  133 , and the acquired setup of MAC address is stored in memory by the MAC address storer  134 . 
         [0053]    Next, at a step S 106 , the connection setup storer  132  is operated to update a record of “unconnected” to “connected”. This is because of the “unconnected” record in memory of the connection setup storer  132 , with which any success in connection with the RIP unit  20  corresponds to an initial connection therewith. Then, at a step S 107 , the printer  10  works in a state connected with the RIP unit  20 . While working, preferably, the printer  10  should be periodically monitored for a connected state with the RIP unit  20 . 
         [0054]    As a result of determination (at the step S 101 ) as to whether the setup of connection with the RIP unit  20  is “connected” or not by collation to the connection setup storer  132  after the startup of printer  10 , if the connection setup is “connected” (Yes), the flow goes to a step S 201  shown in  FIG. 8 , where the printer  10  is operated to output from the LAN port X a WOL signal containing a MAC address stored in memory of the MAC address storer  134 . The WOL processor  230  at the RIP unit  20  receives the WOL signal, responding thereto by making an automatic startup of RIP unit  20 . The RIP unit  20  is thereby started in concert with the printer 
         [0055]    There may be a mismatch of MAC address due to a replacement of the RIP unit  20  with another equipment. This will result in a failed automatic start. Therefore, after replacement of RIP unit  20 , the network manager should manually power on the new RIP unit  20  to make up an initial connection. 
         [0056]    Then, at a step S 202 , there is made a first trial of connection with the RIP unit  20  using an address set stored in memory of the IP setup storer  133 , as an IP address setup. The address set stored in memory of the IP setup storer  133  is an address set employed in a previous success of connection, and will lead to a successful connection subject to an unchanged address set at the RIP unit  20 . 
         [0057]    If the connection is failed (No at a step S 203 ), the flow goes to a step S 208  to determine whether or not the preset time interval has elapsed. Unless the time interval has elapsed (No at the step S 208 ), the flow goes to a step S 210 , to make a trial of connection with the RIP unit  20  using the next address set, as an IP address setup. It is noted that the connection trials are made in order of “setup  1 ”, “setup  2 ”, “setup  3 ”, “setup  1 ”, “setup  2 ”, . . . . 
         [0058]    Such trials of connection are repeated by changing the address set in order. As a result, if the preset time interval has elapsed (Yes at the step S 208 ), the flow goes to a step S 209 , where the printer  10  works, assuming a cancelled connection with the RIP unit  20  followed by a currently unconnected state, while the connection setup storer  132  is left as it has recorded “connected”. 
         [0059]    On the other hand, in success of connection with the RIP unit  20  using some address set (Yes at the step S 203 ), the flow goes to a step S 204  for acquisition of a setup of MAC address from the RIP unit  20 . Then, if the address set in success of connection is different from an address set stored in memory of the IP setup storer  133 , or if the acquired MAC address is different from a MAC address stored in memory of the MAC address storer  134  (Yes at a step S 205 ), the flow goes to a step S 206  to update the content by a latest content. If the address set in success of connection is different from an address set stored in memory of the IP setup storer  133 , this case corresponds to a changed address set at the RIP unit  20 . If the acquired MAC address is different from a MAC address stored in memory of the MAC address storer  134 , it corresponds to a replacement of RIP unit  20 . 
         [0060]    Then, at a step S 207 , the printer  10  works in a state connected with the RIP unit  20 . While working, preferably, the printer  10  should be periodically monitored for a connected state with the RIP unit  20 . 
         [0061]    As will be seen from the foregoing description, according to the second embodiment example, the network manager can make up an interconnection between printer  10  and RIP unit  20  by simply selecting a setup of address set at the RIP unit  20 . Accordingly, it is permitted in an image forming apparatus having a plurality of interfaces connected to a plurality of networks including a network connected with an image processor, to facilitate setting up connections of networks with the image processor. It also is permitted to start the RIP unit  20  in concert with the printer  10 . 
         [0062]    While the preferred embodiments of the present invention have been described using specified terms, such description is for illustrative purposes, and it is to be understood that changes and variations may be made without departing from the spirit or scope of the following claims. For instance, in the present invention, we can suppose animation data as image data to be formed. 
         [0063]    This application is based upon the Japanese Patent Application No. 2008-277173, filed on Oct. 28, 2008, and the entire content of which is incorporated by reference herein.
An image forming apparatus is connected to a plurality of networks including a network connected with an image processor and includes a storer for storing in memory a plurality of address sets each composed of a first kind address of the image forming apparatus and a first kind address of the image processor, and a communication controller to employ the plurality of address sets stored in memory of the storer, for a sequence of trials of connection with the image processor to determine a connectable address set to use for communications with the image processor, as the image processor is adapted for storage of a plurality of address sets each composed of a first kind address of the image processor and a first kind address of the image forming apparatus.