JP2000172470A - Device and method for print control - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress increase in the network traffic in a tandem printing process. SOLUTION: A controller 102 connects an image data network 101 and a network 100. When a PC on the network 100 makes a request for tandem print, the controller 102 generates and sends image data to printers where the tandem printing is carried out. At this time, if the printers are different in output resolution from each other and do not have a resolution converting function, image data of resolution matching to the printers are generated and sent to all the printers at the same time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing control apparatus and method for controlling a printer connected to a network, for example.

[0002]

2. Description of the Related Art Recently, copiers have been multi-functionalized by digitization and systemization. In addition to the integration of the FAX function, the printer function is added to the network and the printer function is added. FIG. 2 shows an office network environment including a digital copying machine. Reference numeral 200 denotes a network such as Ethernet to which network devices such as a personal computer, a printer, and a digital copier in the office are connected. 2
Reference numeral 01 denotes a server personal computer (hereinafter, PC) to which a scanner of a digital copying machine is connected. 20
Reference numeral 2 denotes a digital copying machine; and 203, a controller for connecting the digital copying machine to a network. Reference numeral 204 denotes a color copying machine; and 205, a controller for connecting the color copying machine to a network. 206, 207 are network printers, 208, 209, 210, 211, 212,
213 is a PC client connected to the network 200. P in such a network environment
When printing out from the C client side,
The client selects one of the network printers 206 and 207, the digital copying machine 202 via the controller 203, or the color copying machine 204 via the controller 205, and sends printout data. Further, when a large number of copies are taken by the digital copying machine 203, it is necessary to output to the network printers 206 and 207 via the network when the processing speed of the digital copying machine is insufficient.

[0003]

Here, not only printout data but also a large amount of data are flowing on the network. Particularly when large image data is flowed, the throughput of the entire network is remarkably large. Will drop. In particular, the transfer of the same print data to a plurality of printers in order to obtain a large amount of print output greatly reduces the network throughput.

It is an object of the present invention to provide a printing control apparatus and a printing control method capable of performing printing from a plurality of printers in parallel while suppressing an increase in the amount of data flowing through a network. I do.

[0005]

In order to achieve the above object, the present invention has the following arrangement. That is, a printing control device that is connected to a plurality of printers and has a function of transmitting data to them at the same time, and a comparison unit that acquires and compares the output resolution of each printer. A determination unit that determines whether there is a printer having a conversion function; and if the determination unit determines that there is a printer that has a resolution conversion function, the image data has a resolution corresponding to one of the printers that does not have the resolution conversion function. And a transmission unit for simultaneously transmitting image data to a printer corresponding to the resolution and a printer having a resolution conversion function.

Preferably, the transmitting means further comprises:
When there is no printer having a resolution conversion function, image data corresponding to each printer is generated, and the image data is transmitted for each printer. Preferably, the transmission unit further includes a printer having a resolution conversion function. Out of the plurality of printers, generates image data adapted to the highest resolution and transmits the image data to the plurality of printers at the same time.Preferably, the transmission unit further includes the same unit when there is no printer having a resolution conversion function. Only for printers having a resolution, image data is generated at a resolution corresponding to those printers, and the image data is simultaneously transmitted to the printers.
The connection is made via a communication path conforming to the 394 standard.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [First Embodiment 1] Here,
According to the present invention, a digital I / F for connecting each device is defined as an IE.
Since the IEEE 1394 serial bus is used, the IEEE
The 94 serial bus will be described in advance.

<Overview of IEEE 1394 Technology> With the advent of home digital VTRs and DVDs, it is necessary to support real-time, high-information-volume data transfer of video data, audio data, and the like. In order to transfer such video and audio data in real time, and to transfer it to a personal computer (PC) or other digital devices, an interface capable of high-speed data transfer with the necessary transfer functions is required. The interface developed from such a viewpoint is IEEE1394-1995 (High P
1394 serial bus).

FIG. 16 shows an example of a network system constructed using a 1394 serial bus. This system is provided with devices A, B, C, D, E, F, G, and H, between AB, between AC, between BD, between DE, and between CF.
, C-G, and C-H are connected by a twisted pair cable of a 1394 serial bus.
The devices A to H are, for example, PC, digital VTR, DV
D, digital camera, hard disk, monitor and the like.

[0010] The connection method between the devices is such that the daisy chain method and the node branch method can be mixed.
A highly flexible connection is possible.

Also, each device has its own unique ID and recognizes each other to form a single network in a range connected by a 1394 serial bus. One 1394 connection between each digital device
Just by sequentially connecting with a serial bus cable, each device plays a role of relay, and constitutes one network as a whole. In addition, it has a function of automatically recognizing the device and recognizing the connection status when the cable is connected to the device by the Plug & Play function, which is a feature of the 1394 serial bus.

In the system shown in FIG. 16, when a device is deleted from the network or newly added, the bus is automatically reset to reset the network configuration up to that time. Then, rebuild a new network. With this function, the configuration of the network at that time can be constantly set and recognized.

The data transfer rate is 100/200 /
It has a transmission rate of 400 Mbps, and a device having a higher transfer rate supports a lower transfer rate and is compatible.

The data transfer mode includes asynchronous data such as control signals (hereinafter referred to as A).
Asynchronous transfer mode for transferring sync data)
There is an isochronous transfer mode for transferring synchronous data (Isochronous data: hereinafter, iso data) such as real-time video data and audio data. This Asyn
In each cycle (usually 125 μS per cycle), the c data and the Iso data follow the transfer of a cycle start packet (CSP) indicating the start of the cycle, followed by the Is data.
o Data is transferred together in a cycle while giving priority to data transfer.

FIG. 17 shows the components of the 1394 serial bus.

The 1394 serial bus has a layer (hierarchical) structure as a whole. As shown in FIG.
The most hardware type is a 1394 serial bus cable, which has a connector port to which a connector of the cable is connected.
There are layers and link layers.

The hardware part is a substantial part of an interface chip. The physical layer performs coding and control related to connectors, and the link layer performs packet transfer and cycle time control.

The transaction layer of the firmware section manages data to be transferred (transacted), and issues commands such as Read and Write.
The serial bus management is a part that manages the connection status and ID of each connected device and manages the configuration of the network.

[0019] The hardware and the firmware are the actual configuration of the 1394 serial bus.

The software application
The layer differs depending on the software used, and is a part that defines how data is placed on the interface.
It is specified by a protocol such as the V protocol.

The above is the configuration of the 1394 serial bus.

FIG. 18 shows an address space in the 1394 serial bus.

Each device (node) connected to the 1394 serial bus always has a 64-bit address unique to each node. By storing this address in the ROM, it is possible to always recognize the node address of oneself and the other party, and perform communication specifying the other party.

The addressing of the 1394 serial bus is based on the IEEE 1212 standard, and the first 10 bits are used for specifying the bus number.
The next 6 bits are used for specifying the node ID number. The remaining 48 bits become the address width given to the device,
Each can be used as a unique address space. The last 28 bits store information such as identification of each device and designation of use conditions as an area of unique data.

The above is the outline of the technology of the 1394 serial bus.

Next, the technical portion which can be said to be a feature of the 1394 serial bus will be described in more detail.

<Electrical Specifications of 1394 Serial Bus> FIG. 19 is a sectional view of a 1394 serial bus cable.

In the 1394 serial bus, a power supply line is provided in a connection cable in addition to two twisted pair signal lines. As a result, power can be supplied to a device having no power supply, a device whose voltage has dropped due to a failure, and the like.

The voltage of the power supply flowing in the power supply line is 8 to 40.
V and the current are specified as a maximum current DC of 1.5 A.

<DS-Link Coding> The data transfer format D used in the 1394 serial bus
FIG. 20 is a diagram illustrating the S-Link coding scheme.

In the 1394 serial bus, DS-Lin
The k (Data / Strobe Link) coding method is adopted.
This DS-Link coding scheme is suitable for high-speed serial data communication, and its configuration requires two signal lines. The main data is sent to one of the twisted pairs,
A strobe signal is sent to the other twisted pair.

On the receiving side, the clock can be reproduced by taking the exclusive OR of this communicated data and the strobe.

Advantages of using the DS-Link coding method include higher transfer efficiency as compared with other serial data transfer methods, and the circuit scale of the controller LSI can be reduced because a PLL circuit is not required.
Since there is no need to send information indicating the idle state when there is no data to be transferred, the power consumption can be reduced by setting the transceiver circuit of each device to the sleep state.

<Sequence of Bus Reset> In the 1394 serial bus, each connected device (node) is given a node ID and recognized as a network configuration.

When there is a change in the network configuration, for example, a change occurs due to an increase or decrease in the number of nodes due to insertion / removal of a node or power ON / OFF, etc., and it is necessary to recognize a new network configuration. Each detected node sends a bus reset signal on the bus,
Enter the mode to recognize the new network configuration. The method of detecting the change at this time is performed by detecting a change in the bias voltage on the 1394 port board.

When a bus reset signal is transmitted from a certain node, the physical layer of each node transmits the bus reset signal to the link layer at the same time as receiving the bus reset signal, and transmits the bus reset signal to another node. . After all the nodes finally detect the bus reset signal, the bus reset is activated.

The bus reset is also activated by the above-described activation by hardware insertion / removal due to cable disconnection or network abnormality or the like, and also by directly issuing a command to the physical layer by host control from a protocol.

Further, when the bus reset is activated, the data transfer is suspended, the data transfer during this period is waited, and after the end, the data transfer is resumed under a new network configuration.

The above is the bus reset sequence.

<Sequence of Node ID Determination> After the bus reset, each node starts an operation of giving an ID to each node in order to construct a new network configuration. The general sequence from the bus reset to the determination of the node ID at this time will be described with reference to the flowcharts of FIGS.

The flowchart of FIG. 21 shows a series of bus operations from the occurrence of a bus reset until the node ID is determined and data transfer can be performed.

First, in step S101, the occurrence of a bus reset in the network is constantly monitored, and if a bus reset occurs due to power ON / OFF of a node, the process proceeds to step S102.

In step S102, from the reset state of the network, a parent-child relationship is declared between the directly connected nodes in order to know the connection status of the new network. As step S103,
When the parent-child relationship is determined between all nodes, step S
One route is determined as 104. Until the parent-child relationship is determined between all nodes, the parent-child relationship is declared in step S102, and the route is not determined.

After the route is determined in step S104, the operation of setting a node ID for giving an ID to each node is performed in step S105. Node IDs are set in a predetermined node order, and I
The setting operation is repeatedly performed until D is given. When the IDs are finally set in all the nodes in step S106, the new network configuration is recognized in all the nodes. And data transfer is started.

In the state of step S107, a mode for monitoring the occurrence of a bus reset again is entered.
When the bus reset occurs, the setting operation from step S101 to step S106 is repeatedly performed.

The flow chart of FIG. 21 has been described above. The flow chart of FIG. 21 shows the part from the bus reset to the route determination and the procedure from the route determination to the end of the ID setting in a more detailed flow chart. Are shown in FIGS. 22 and 23, respectively.

First, the flowchart of FIG. 22 will be described.

When a bus reset occurs in step S201, the network configuration is reset once. The occurrence of a bus reset is constantly monitored in step S201.

Next, in step S202, as a first step of re-recognizing the reset network connection status, a flag indicating a leaf (node) is set for each device. Further, in step S203, each device checks how many ports it has are connected to other nodes.

In accordance with the result of the number of ports in step S204, the number of undefined (parent-child relationship is not determined) ports is checked in order to start the declaration of the parent-child relationship.
Immediately after the bus reset, the number of ports = the number of undefined ports. However, as the parent-child relationship is determined, the number of undefined ports detected in step S204 changes.

First, immediately after a bus reset, only a leaf can declare a parent-child relationship. A leaf can be known by checking the number of ports in step S203. In step S205, the leaf declares "I am a child and the other is a parent" to the node connected thereto, and ends the operation.

A node which has a plurality of ports in step S203 and is recognized as a branch has a number of undefined ports> 1 in step S204 immediately after the bus reset.
Moving to step S206, a flag of branch is first set, and in step S207, the process waits for reception of "parent" in the parent-child relationship declaration from the leaf.

The leaf declares the parent-child relationship, and the branch that has received the declaration in step S207 appropriately returns to step S20.
Confirm the number of undefined ports of 4 and find that the number of undefined ports is 1
If it becomes, it becomes possible to declare “I am a child” in step S205 for the node connected to the remaining port. After the second time, step S204
Even if the number of undefined ports is checked in step S207, for a branch having two or more ports, the process waits again in step S207 to accept a "parent" from a leaf or another branch.

Finally, if any one of the branches or exceptionally leaves (because it did not operate quickly enough to make a child declaration) becomes zero as a result of the number of undefined ports in step S204, In this case, the declaration of the parent-child relationship of the entire network has been completed, and the only node for which the number of undefined ports has become zero (all are determined as parent ports) is flagged as a root in step S208, and the root is set in step S209 Is recognized.

In this manner, the process from the bus reset shown in FIG. 22 to the declaration of the parent-child relationship between all the nodes in the network is completed.

Next, the flowchart of FIG. 23 will be described.

First, in the sequence up to FIG.
Since the information of the flag of each node such as branch and route is set, classification is performed in step S301 based on this.

As a task of assigning an ID to each node, the ID can be set first from the leaf. The IDs are set in ascending order of leaf → branch → route (node number = 0).

In step S302, the number N (N is a natural number) of leaves existing in the network is set. Thereafter, in step S303, each leaf requests the root to give an ID. If there are a plurality of such requests, the route performs arbitration (operation of arbitration into one) in step S304, and proceeds to step S3.
As 05, an ID number is given to one winning node, and a failure result is notified to the losing node. In step S306, the leaf whose ID acquisition has failed fails issues an ID request again, and repeats the same operation. In step S307, the ID information of the node is transferred to all the nodes by broadcasting from the leaf whose ID has been acquired. One node I
When the broadcasting of the D information is completed, step S30
As 8, the number of remaining leaves is reduced by one. here,
In step S309, when the number of the remaining leaves is one or more, the operation from the ID request in step S303 is repeatedly performed, and finally, when all the leaves broadcast the ID information, N = 0 in step S309, and the next Moves to the branch ID setting.

The setting of the branch ID is performed in the same manner as in the case of the leaf.

First, at step S310, the number M (M is a natural number) of branches existing in the network is set. Thereafter, in step S311, each branch requests the root to give an ID. On the other hand, for the route, arbitration is performed in step S312, and the branch is given in order from the winning branch to the next youngest number given to the leaf. In step S313, the root notifies the branch that issued the request of ID information or a failure result, and in step S314, the branch whose ID acquisition has failed fails issues an ID request again and repeats the same operation. In step S315, the ID information of the node is broadcast and transferred to all the nodes from the branch where the ID has been obtained. When the broadcast of the one node ID information ends, the number of remaining branches is reduced by one in step S316. Here, step S3
When the number of the remaining branches is 1 or more, the operation from the ID request in step S311 is repeated until all branches finally broadcast ID information. When all the branches have acquired the node IDs, M = 0 in step S317, and the branch ID acquisition mode ends.

At this point, since only the root node has not acquired the ID information at the end, step S
318 is set as the ID number of the hour and minute.
Broadcast D information.

Thus, as shown in FIG. 23, the procedure from the determination of the parent-child relationship to the setting of the IDs of all the nodes is completed.

Next, the operation in the actual network shown in FIG. 24 as an example will be described with reference to FIG.

Referring to FIG. 24, the (root) node B
Are directly connected to node A and node C,
Further, a node D is directly connected below the node C, and a node E and a node F are directly connected below the node D in a hierarchical structure. The procedure for determining the hierarchical structure, the root node, and the node ID will be described below.

After the bus reset, a parent-child relationship is declared between the directly connected ports of each node in order to recognize the connection status of each node. The parent and child can be said to be such that the parent is higher in the hierarchical structure and the child is lower.

In FIG. 24, the node A first declares the parent-child relationship after the bus reset. Basically, a node (called a leaf) having a connection to only one port of the node can declare a parent-child relationship. Since the user can first know that only one port is connected, it recognizes that this is the edge of the network, and the parent-child relationship is determined from the node that operates earlier in the network. In this manner, the port on the side that has declared the parent-child relationship (node A between AB) is set as a child, and the port on the other side (node B) is set as a parent. Thus, between node AB, child-parent, node E-
The child-parent is determined between D and the child-parent is determined between the nodes FD.

Further up in the hierarchy, among nodes having a plurality of connection ports (referred to as branches), a parent-child relationship is declared further higher in order from a node that has received a parent-child relationship declaration from another node. To go. In FIG. 24, first, after the parent-child relationship between the node D and DE and between DF is determined,
The parent-child relationship is declared for node C, and as a result, child-parent is determined between nodes D and C.

The node C receiving the parent-child relationship declaration from the node D becomes the node B connected to another port.
Declares a parent-child relationship. As a result, a child-parent is determined between the nodes C and B.

In this way, a hierarchical structure as shown in FIG. 24 is formed, and the node B which has become the parent in all finally connected ports is determined as the root node. There is only one route in one network configuration.

In FIG. 24, the node B is determined to be the root node. This is because the node B, which has received the parent-child relationship declaration from the node A, makes the parent-child relationship declaration to other nodes at an early timing. If so, the root node may have moved to another node. That is, any node may become a root node depending on the transmission timing, and the root node is not always constant even in the same network configuration.

When the root node is determined, the process enters a mode for determining each node ID. Here, all nodes notify their determined node IDs to all other nodes (broadcast function).

The self ID information includes its own node number, information on the connected position, the number of ports it has, the number of connected ports, and information on the parent-child relationship of each port.

As a procedure for assigning node ID numbers, first, nodes can be started from a node (leaf) having a connection to only one port, and node numbers = 0, 1, 2, and so on are assigned in this order. .

The node that has obtained the node ID broadcasts information including the node number to each node. As a result, it is recognized that the ID number is “assigned”.

When all the leaves have acquired their own node IDs, the next step is to move to a branch, and the node ID number following the leaf is assigned to each node. Similarly to the leaf, the node ID information is broadcast sequentially from the branch to which the node ID number is assigned, and finally, the root node broadcasts its own ID information. That is, the root always owns the maximum node ID number.

As described above, the assignment of the node IDs of the entire hierarchical structure is completed, the network configuration is reconstructed, and the bus initialization operation is completed.

<Arbitration> In the 1394 serial bus, arbitration (arbitration) of the right to use the bus is always performed prior to data transfer. Since the 1394 serial bus is a logical bus-type network in which each device connected individually relays the transferred signal to transmit the same signal to all devices in the network, packet collision occurs. Arbitration is necessary to prevent This allows only one node to transfer at a given time.

As a diagram for explaining arbitration, FIG. 25A shows a bus use request diagram, and FIG. 25B shows a bus use permission diagram.

When arbitration starts, one or more nodes issue a bus use request to the parent node. Nodes C and F in FIG. 25A are nodes that have issued a bus use right request. The parent node (node A in FIG. 25) that has received this further issues (relays) a request for the right to use the bus toward the parent node. This request is finally delivered to the arbitration route.

The root node receiving the bus use request determines which node uses the bus. This arbitration work can be performed only by the root node, and the node that has won the arbitration is given permission to use the bus. FIG.
In (b), use permission is given to the node C, and use of the node F is rejected. A DP (data prefix) packet is sent to the node that has lost the arbitration to notify that the node has been rejected. The rejected node use request waits until the next arbitration.

As described above, the node that has won the arbitration and obtained the bus use permission can start transferring data thereafter.

Here, a series of arbitration flows will be described with reference to a flowchart shown in FIG.

In order for a node to be able to start data transfer,
The bus must be idle. In order to recognize that the data transfer that has been performed earlier is completed and the bus is currently idle, a predetermined idle time gap (eg, a subaction gap) set individually in each transfer mode is required. Each node determines that its own transfer can be started by passing).

In step S401, it is determined whether a predetermined gap length corresponding to each data to be transferred, such as Async data and Iso data, has been obtained. Unless the predetermined gap length is obtained, the request for the right to use the bus required to start the transfer cannot be made, so the process waits until the predetermined gap length is obtained.

If a predetermined gap length is obtained in step S401, it is determined in step S402 whether there is data to be transferred. If so, a request for a bus use right is issued in step S403 to secure a bus for transfer. Emit to the route. At this time, the transmission of the signal indicating the request for the right to use the bus is finally delivered to the route while relaying each device in the network, as shown in FIG. If there is no data to be transferred in step S402,
Wait as it is.

Next, at step S404, when the route receives one or more bus use requests at step S403, the route checks at step S405 the number of nodes that have issued use requests. If the selection value in step S405 is the number of nodes = 1 (the number of nodes that issued the use right request is one), the immediately subsequent bus use permission is given to that node. The selection value in step S405 is the number of nodes> 1
If (the number of nodes requesting the use is plural), the root performs an arbitration operation of deciding one node to which use permission is given in step S406. This arbitration work is fair, and the same node does not always obtain permission each time, and the right is equally given.

As step S407, step S40
In step 6, a selection is made to divide the route into one node whose route has been arbitrated and the use of which has been granted, and another node which has lost the route. Here, for one node that has been arbitrated and has obtained use permission, or a node that has obtained use permission without arbitration with the number of use request nodes = 1 from the selection value in step S405, the route is set to that node as step S408. A permission signal is sent to it. The node that has received the permission signal starts transferring data (packets) to be transferred immediately after receiving the permission signal. Further, the nodes that have been defeated in the arbitration in step S406 and have not been permitted to use the bus are given step S406.
At step 409, a DP (data prefix) packet indicating an arbitration failure is sent from the root, and the node that has received the packet returns to step S401 to issue a bus use request for performing the transfer again, until the predetermined gap length is obtained. stand by.

The flow of the arbitration has been described above with reference to the flowchart of FIG.

<Asynchronous Transfer> The asynchronous transfer is an asynchronous transfer. FIG. 27 shows a temporal transition state in the asynchronous transfer. The first sub-action gap in FIG. 27 indicates the idle state of the bus. When the idle time reaches a certain value, the node desiring transfer determines that the bus can be used and executes arbitration for acquiring the bus.

When the bus use permission is obtained by arbitration, the data transfer is executed in the form of a packet.
After the data transfer, the receiving node sets ack (reception confirmation return code) of the reception result for the transferred data to a.
After a short gap of ck gap, transfer A is completed by returning and responding or sending a response packet. The ack is composed of 4-bit information and a 4-bit checksum, and includes information such as success, busy status, and pending status, and is immediately returned to the source node.

Next, FIG. 28 shows an example of the packet format of the asynchronous transfer.

The packet has a header part in addition to the data part and the data CRC for error correction. The header part has the destination node ID, the source node ID, the transfer data length and the like as shown in FIG. Various codes are written,
The transfer is performed.

Asynchronous transfer is one-to-one communication from a self-node to a partner node. The packet transferred from the transfer source node is distributed to each node in the network, but the address other than its own address is ignored, so that only one destination node reads the packet.

The above is the description of the asynchronous transfer.

<Isochronous (Synchronous) Transfer> Isochronous transfer is synchronous transfer. This isochronous transfer, which can be said to be the greatest feature of the 1394 serial bus,
In particular, this transfer mode is suitable for transferring data that requires real-time transfer, such as multimedia data such as VIDEO video data and audio data.

Also, if the asynchronous transfer (asynchronous) is 1
Unlike the one-to-one transfer, the isochronous transfer is uniformly transferred from one transfer source node to all other nodes by the broadcast function.

FIG. 29 is a diagram showing a temporal transition state in isochronous transfer.

The isochronous transfer is executed on the bus at regular intervals. This time interval is called an isochronous cycle. The isochronous cycle time is 125 μS. A cycle start packet indicates the start time of each cycle, and plays a role of adjusting the time of each node. A node called a cycle master transmits a cycle start packet, and after a transfer in a previous cycle is completed, a predetermined idle period (subaction gap) is passed, and then the start of this cycle is announced. Send a cycle start packet. The time interval at which this cycle start packet is transmitted is 125 μS.

FIG. 29 shows channel A, channel B,
As indicated by the channel C, a plurality of types of packets can be separately transferred by being given channel IDs in one cycle. This allows real-time transfer between a plurality of nodes at the same time, and the receiving node fetches only the data of the channel ID desired by itself. The channel ID does not represent the address of the transmission destination, but merely gives a logical number for the data. Therefore, the transmission of a certain packet is 1
From one source node to all other nodes,
It will be transferred by broadcast.

Prior to packet transmission in isochronous transfer, arbitration is performed as in asynchronous transfer. However, since the communication is not one-to-one communication as in the asynchronous transfer, there is no ack (reception confirmation reply code) in the isochronous transfer.

The iso gap (isochronous gap) shown in FIG. 29 indicates an idle period necessary for recognizing that the bus is empty before performing the isochronous transfer. After the predetermined idle period has elapsed, a node that wishes to perform isochronous transfer determines that the bus is free, and can perform arbitration before transfer.

Next, an example of a packet format for isochronous transfer will be described with reference to FIG.

Each packet divided into each channel has a header portion in addition to a data portion and data CRC for error correction. The header portion has a transfer data length and a channel length as shown in FIG. NO and other various codes and a header CRC for error correction are written and transferred.

The above is the description of the isochronous transfer.

<Bus Cycle> In an actual transfer on the 1394 serial bus, isochronous transfer and asynchronous transfer can coexist. FIG. 31 shows a state of a temporal transition of the transfer state on the bus in which the isochronous transfer and the asynchronous transfer are mixed at that time.

The isochronous transfer is executed prior to the asynchronous transfer. The reason is that after the cycle start packet, the isochronous transfer can be started with a gap length (isochronous gap) shorter than the gap length (subaction gap) of the idle period required to start the asynchronous transfer. . Therefore, the isochronous transfer is executed with priority over the asynchronous transfer.

In the general bus cycle shown in FIG. 31, a cycle start packet is transferred from the cycle master to each node at the start of cycle #m. As a result, each node adjusts the time, and after a predetermined idle period (isochronous gap), the node that should perform isochronous transfer performs arbitration and starts packet transfer. In FIG. 31, the channel e, the channel s, and the channel k are sequentially and isochronously transferred.

After the operations from the arbitration to the packet transfer are repeated for the given channels, when all the isochronous transfers in the cycle #m are completed, the asynchronous transfer can be performed.

When the idle time reaches the sub-action gap where asynchronous transfer is possible, the node that wishes to perform asynchronous transfer determines that arbitration can be executed.

However, the period during which the asynchronous transfer can be performed is a time (cycle sy) for transferring the next cycle start packet after the completion of the isochronous transfer.
nch) only when a subaction gap for activating the asynchronous transfer is obtained.

In cycle #m of FIG. 31, two packets (packet 1 and packet 2) of isochronous transfer for three channels and then asynchronous transfer (including ack) are transferred. After this asynchronous packet 2, a time (cycle) to start cycle m + 1
e sync), the transfer in cycle #m ends here.

However, the time (c) at which the next cycle start packet should be transmitted during the asynchronous or synchronous transfer operation
If (cycle synch) is reached, a cycle start packet of the next cycle is transmitted after waiting for an idle period after the transfer is completed without forcibly interrupting the transfer. That is, when one cycle continues for 125 μS or more, it is assumed that the next cycle is shortened by that much from the reference 125 μS. As described above, the isochronous cycle can be exceeded or shortened on the basis of 125 μS.

However, the isochronous transfer is always executed if necessary every cycle to maintain the real-time transfer, and the asynchronous transfer may be transferred to the next and subsequent cycles due to the shortened cycle time.

A cycle including such delay information
Controlled by the master.

The above is the description of the IEEE 1394 serial bus.

<Structure of Print System> Next, the present print system will be described focusing on the digital copying machine controller. FIG. 1 shows the print system. A personal computer and a printer are connected to the network 100. Network 1
Reference numeral 01 denotes a network provided for image transfer.
It is based on EEE1394. Controller 1
02 is the network 100 and the image network 101
, And controls input and output of image data. The color copier 103, the printers 104 and 105, and the black and white digital copier 106 are connected to the image network 101. Personal computers 107, 108, 1
09, 110, 111, and 112 are personal computers (hereinafter, PCs) connected to the network 100. When printing out from the PC, data is sent to a desired printer or copier via the network 100, the controller 102, and the image data network 101.

Next, the image data controller 102 will be described. FIG. 3 shows a block diagram of the image data controller. The CPU 301 is a CPU on the image data controller, and controls the exchange of data with a PC or a printer on a network. CPU data bus 30
2 includes a card bus controller 304 and a ROM
305, RAM 306, hard disk controller 3
07 is connected. The card bus controller 304 controls the card bus 303 for mounting a function board for adding a function to the image data controller. The ROM 305 is a program memory in which control software for the image data controller is stored. Part of the program area is composed of flash ROM,
The program memory can be rewritten from a facsimile data modem 311 described later or an interface terminal (not shown) via a telephone line. RAM 306 is DRA
It is composed of M or SRAM, and can be used as a work area for a normal program or as an image data memory. The hard disk controller 307 controls reading and writing of the hard disk 312. The hard disk 312 is used for storing image data and for storing program software. The hard disk controller 307 performs data compression when reading image data and data expansion when reading image data.

Next, each functional board connected to the card bus 303 will be described. The network interface card 308 performs an interface for a network to which the PC and the image data controller in FIG. 1 are connected. In this configuration, a corresponding card can be installed on a physical interface that constructs a network such as Ethernet or token ring.

Image Network Interface Card 3
Reference numeral 09 denotes a network interface for transferring image data between the color copier, the printer, the black and white digital copier and the image data controller shown in FIG. This image network needs to be configured with a high-speed bus that can transfer a large amount of image data. Accordingly, in the present embodiment, the description will be made assuming that the IEEE 1394, which is a high performance serial bus, which has attracted attention in recent years, is used as this image data network, but the present invention is not necessarily limited to this.

The raster image expansion card 310 expands the printer description language into bitmap data. This is not used when the printer on the image network individually supports the page description language. However, even when a dumb printer that simply prints bitmap data is connected on the image network, the PC on the network side can use the printer as a page description language compatible printer without being aware of the fact. . Also, support for many page description languages can be handled by replacing a function board with a card bus. Further, the program memory area of the raster image development card is configured to be loadable like a flash ROM or a RAM, and a plurality of page description language raster image development programs are stored in the hard disk 312 in advance. Therefore, it is possible to load the page description language desired by the user from the hard disk 312 into the program memory of the raster image development card 310. The FAX / data modem card 311 is connected to a telephone line to perform FAX transmission / reception, and can be connected to a remote PC or workstation as a data modem.

Next, the operation of the image data controller and the flow of data on the network will be described.

<In the case where page description language (PDL) data is sent from a PC on the network and printout is performed> The printer 105 is selected from the PC 107 in FIG. 1 and PDL printing is designated. At that time, the PDL data is transferred to the image data controller 1 via the network 100.
02 is input.

In the image data controller shown in FIG.
The L data is input to the raster image development 310 card.

FIG. 7 is a block diagram of the network interface card 308. Reference numeral 701 denotes a card bus interface, 702 denotes an Ethernet protocol controller which is currently widely used, 704 denotes a data transmission / reception buffer, and 704 denotes 110base2 and 10baseT.
An Ethernet transceiver including an interface with a network-connected medium. 70
Reference numeral 5 denotes a connector corresponding to the network medium.

CPU 301 of image data controller
When the data transmitted via the network interface card is determined to be PDL data, the data is transmitted to the raster image development card.

FIG. 6 is a block diagram of the raster image development card 310. 601 is a card bus interface, 602 is a raster image processor that expands PDL data to generate bitmap data, and 603 is R as a program area for the raster image processor.
OM and 604 are a bitmap memory for storing bitmap data, and 605 is a bitmap memory controller for controlling reading and writing of the bitmap memory. The PDL data input to the raster image development card is sent to a raster image processor 602 via a card bus interface 601, where bitmap data is generated and sent to a bitmap memory 604 via a bitmap memory controller 605. Is stored. Then, the bitmap data is transferred to the image network interface card 309.

FIG. 8 is a block diagram of the image network interface card 309. 801 is a card bus interface, 802 is a fast bus for transferring image data.
This is an in-fast-out memory (hereinafter, FIFO). Reference numeral 803 denotes an IEEE 1394 link controller chip which is a high-speed serial interface employed in this embodiment. Reference numeral 804 denotes an IEEE 1394 physical interface, and reference numeral 805 denotes a connector to which an image network interface cable is connected. Up to three connectors can be connected to one physical interface. CPU 301 of the image data controller 102
Then, in order to transfer the bitmap data from the PC to the printer 105 specified, the data is transferred through the image network interface card 309 in the following procedure.・ Image data controller → Printer: Transfer data transmission request command ・ Printer → Image data controller: Transfer data reception confirmation command ・ Image data controller → Printer: Print data start command transfer ・ Image data controller → Printer: Bitmap data transfer ・Image data controller → Printer: Print data end command transfer ・ Printer → Image data controller: Print data reception confirmation command In the data transfer mode of IEEE1394, data is transferred to a predetermined transfer destination, and the receiving side confirms data reception. And an isochronous transfer mode in which data is transferred to an unspecified transfer destination and no confirmation is sent from the receiving side. Here, the command is transferred in the asynchronous transfer mode, and the bitmap data is transferred in the isochronous transfer mode.
8, command data is input to a link chip controller 803 via a card bus interface 801 and transferred as asynchronous data. On the other hand, the bitmap data is stored in the card bus interface 80.
1 is written to the FIFO 802 once. The link chip controller 803 uses the FIFO 802 to transfer bitmap data in the isochronous transfer mode.
, And data transfer is performed.

FIG. 9 is a block diagram of the printers 103 to 106. Reference numeral 901 denotes a CPU that performs all controls in the printer, such as mechatronic control of the printer and reception of bitmap data; 902, a memory in which a program of the CPU 901 is stored; 903, a RAM of the CPU 901;
The CPU address of the PU 901, the data bus, and 905 are IEEEs that interface with the image network 101.
E1394 link controller, 906 is IEEE13
Reference numeral 907 denotes an IEEE 1394 connector; 908, a fast-in, fast-out memory (hereinafter, FIFO) for temporarily storing bitmap data transferred by isochronous transfer;
9 corresponds to the FI in accordance with the operation timing of the printer engine.
A video data controller for controlling reading of bitmap data from the FO 908, a laser driver 910 for printing, an engine controller 911 for controlling a motor of a printer engine and a mechatronic control such as a sheet feeding control, and a reference numeral 912 is a printer engine. .

Next, command and data transfer between the image network interface card 309 and the printer will be described with reference to FIG. # 1001 A data transmission request command is transferred from the image data controller 102 to a desired printer in the asynchronous transfer mode. # 1002 The printer receives the data in the asynchronous transfer mode and confirms it (hereinafter ACK) by the IE in FIG.
Sent from the EE1394 link controller 905. # 1003 In the printer, the CPU 901 receives a data transmission request command. # 1004 The CPU 901 checks the current status of the printer, and if a printout operation is possible, transfers a data transmission request permission command (data reception confirmation command) to the image data controller. This command is transferred in the asynchronous transfer mode by the IEEE 1394 link controller 905. # 1005 In the image data controller, the ACK of the data transmission request permission command data is transmitted from the IEEE 1394 link controller 804. # 1006 In the image data controller 102, the CPU 301 receives a data transmission request permission command. # 1007 Image data is transferred from the image data controller 102 to the printer in the isochronous transfer mode. This data transfer will be described later. # 1008 The image data controller 102 transfers a print data end command to the printer after the image data transfer ends. # 1009 In the printer, the ACK of the print data end command is returned from the IEEE 1394 link controller 905 in FIG. # 1010 In the printer, the CPU 901 receives a print data end command. # 1011 From printer to image data controller 1
02, a lint data reception confirmation command is sent. In the # 1012 image data controller, the ACK of the print data reception confirmation command is 804 IEEE 139
Returned from 4-link controller. -The # 1013 image data controller receives a print data reception confirmation command.

As described above, the command transfer by the asynchronous transfer and the image data transfer by the isochronous transfer are performed.

Next, how the image data transfer by the isochronous transfer is performed will be described.

125 μS for isochronous data transfer
Each time, packet transfer is performed, and by securing a channel in advance, time guarantee of data transfer can be obtained.

Therefore, it is necessary for the image data controller 102 to check the printer speed for the printer to be transferred in advance and secure a channel according to the performance. This image data controller 1
Operation 02 will be described with reference to the flowchart of FIG. # 1101 The image data controller checks the printer performance with the printer. Here, printer B
The time of the D cycle (hereinafter, 1H time) and the number of 1H pixels are confirmed. The BD cycle is a main scanning cycle of a laser beam that scans a photosensitive drum to form an image when a printer uses a laser beam method. The laser beam is scanned by a sensor disposed on a scanning line of the laser beam. It is detected as a time interval to be detected. # 1102 Next, the required channel width is calculated based on the confirmed printer performance. For example, 1H time = 375μ
S, 1H pixel count = 7200 pixels, 125 μS
7200 / (375/125) = 2 per packet at intervals
It is necessary to temporally guarantee data transfer for 400 pixels. For a binary printer, 2 per packet
What is necessary is to secure a data transfer channel for 400 bits. # 1103 The image data controller uses IEEE1
A necessary transfer channel is secured via the 394 link controller. # 1104 When a channel necessary for the printer is secured, the image data controller attaches a start and end header of one page of image data to the image data, or attaches a start and end header of 1H of image data to the image data. Generate transfer data. Here, how to generate transfer data will be described with reference to FIG.

In the upper part of FIG. 12, one packet is 125 μsec.
c indicates a channel formed for each c and in which a shaded portion in the packet is secured. The shaded channel is composed of a header + image data. The header includes codes of page start, between pages, page end, within 1H period, and 1H end so that the printer which has received the transferred data can recognize the position of the image data in the channel. Things. For example, 1H
Data of 2400 pixels out of 7200 pixels is 1
When transferring packets for each channel, data transfer of 7,200 pixels for 1H is performed for three packets and three channels. The image data generated at this time is as shown in FIG. In the case of image data transfer for n lines (n is a positive number), 3n channel data are transferred, and the header of the header is the page start (A0h), 1H start (A8h) + image data, the second packet Packets are between pages (A
2h) 1H period (AAh) + image data, the third packet is between pages (A2h), 1H end (ADh) + image data. In the same manner as described below, the header is added to the image data and the data is transmitted. In the 3nth packet, page end (A5h), 1H end (ADh) + image data are transferred, and image data transfer for one page ends.

Now, returning to the flowchart of FIG.
In # 1105, the transfer data generated by the image data controller 102 is transferred to the FIFO 802 in FIG.
The size of the FIFO 802 must be at least as large as the data size to be transferred in one packet. After the transfer data is stored in the # 1106 FIFO 802, the data is transferred to the IEEE 1394 link controller 803. # 1107 As shown in FIG. 12, the transfer data is created and the data transfer is repeatedly performed while the header is attached to the image data. The print data transfer is completed when the data transfer for one page is completed.

Next, the timing at which the printer outputs print data after receiving the transfer data will be described with reference to the timing chart of FIG.

# 1301 represents a packet cycle. The hatched portion therein is the image data in the isochronous transfer mode.

# 1302 represents the timing of writing data to the FIFO 908 in FIG. The transferred data is an IEEE 1394 link controller 905
Is written to the FIFO. # 1303 represents the BD timing of the printer. In this example, the timing is such that a BD occurs once in three packets.
# 1304 indicates the read timing of the FIFO 908. After three packets of data have been written to the FIFO, the FIFO is read out in synchronization with the next BD. # 1305 indicates that the printing operation is being performed, and the printing operation is performed while the FIFO is being read.

As described above, the PDL output from the PC
The data is developed into image data by the image data controller and then transferred to the selected printer via the image data network.

<Tandem print processing> Next, a case where page description language (PDL) data is sent from a PC on a network and print output is performed by a plurality of printers will be described.

When printing a plurality of copies in a short time, the same print data can be transferred to a plurality of printers to realize a plurality of copies. This will be described with reference to the flowchart of FIG. FIG.
Is a system flow according to data transmitted from the PC to the image data controller 102 and the printer.

In step # 401, "tandem print" is selected from the printer name output by the PC application. This selection is made by designating “tandem print” as the printer name on the screen in FIG. The screen of FIG. 5 is displayed when the printer driver of the PC connected to the network is started.

In # 402, the image data controller 1
02 checks whether a desired printer is connected to the image network 101. The desired printer here is, for example, a printer specified in advance for tandem printing.

In step # 403, the image data controller 1
02, the user is informed that a tandem print is to be performed to a desired printer.

In # 404, the PC transfers the PDL data to the raster image development card 301 of the image data controller 102.

In step # 405, the bitmap data is developed by the raster image development card 301.

At step # 406, the image data controller 1
02 to the desired printer.

In step # 407, printout is performed by each printer that has received the bitmap data.

Next, a method of transferring commands and data between the image data controller 102 and a printer that performs tandem printing will be described with reference to FIG. In the figure, a thin solid line indicates asynchronous transfer, a thin dotted line indicates asynchronous transfer ACK, and a thick solid line indicates isochronous transfer. FIG. 14 shows a sequence from the time when the transfer of the PDL data from the PC to the image data controller 102 and the rasterization are completed.

# 1401 The tandem print request command is transferred from the image data controller to the printer 1 on the image data network in the asynchronous transfer mode. With this command, the image data controller grasps the performance of the printer for performing tandem printing.

# 1402 ACK of asynchronous transfer
Is returned to the image data controller.

# 1403 The printer 1 transfers a tandem print permission command to return the printer performance required for performing tandem printing.

# 1404 ACK for asynchronous transfer
Is returned to the printer 2.

# 1405 Similarly, a tandem print request command is transferred to the printer 2.

# 1406 ACK for asynchronous transfer
Is returned to the image data controller.

# 1407 Similarly, a tandem print permission command is sent from the printer 2 to the image data controller.

# 1408 ACK for asynchronous transfer
Is returned to the printer 2.

# 1409 The image controller uses the isochronous transfer mode to notify the printer 1 of the channel number of the isochronous transfer data to be received by the printer 1 and the printer 2.

# 1410 ACK is returned to the image controller.

# 1411 Similarly, the isochronous channel number is transferred to the printer 2.

# 1412 ACK is returned to the image controller.

# 1413 The image data is transferred using the isochronous transfer mode. Since the isochronous transfer is a broadcast transfer, the printers 1 and 2 whose channel numbers have been notified in advance can receive data in one transfer. The image data transfer is repeatedly performed in this manner.

# 1414 The image data controller transmits the tandem print end to the printer 1. # 1415 Acknowledgment of asynchronous transfer is returned to the image controller. # 1416 Similarly, a tandem print end command is transferred to the printer 2. # 1417 ACK of asynchronous transfer is returned to the image controller.

As described above, when a plurality of copies are to be printed, data can be simultaneously transferred to a plurality of printers by isochronous transfer broadcasting.

In the above procedure, the performance of each printer is checked by the image controller 102 before the transfer of the print data. However, the configuration may be such that the performance of the printer is grasped in advance.

<Network Construction> IEEE 1394
After the power is turned on by the link controller, a topology map is created, and all nodes connected on the network are recognized. At that time, node numbers are assigned to all nodes according to the physical connection state and initial settings, and one root node (parent) is assigned from that node.
Is selected.

When a topology map is created in the image data network, it is necessary to initialize the image data controller 102 so that it is always selected as the root node. As a result, the subsequent image data network management can be smoothly performed. The image network initialization control of the image data controller will be described with reference to the flowchart of FIG.

# 1501 When power is turned on to any device on the image data network or the like, the
A bus reset specified by 94 occurs. Then, all I connected to the image data network
The EEE1394 physical interface detects a bus reset and performs a reset release sequence.

# 1502 Each node on the image network performs a predetermined control on the port connected after a predetermined wait time, and waits for a node number allocation to create a topology map.

In step # 1503, if it is determined that the image data controller is not the root node, the image data controller is set as a waiting time before declaring a parent-child relationship with another connected node. Increase wait time and reset (# 1504), # 1
At 501, the bus reset sequence is run again to recreate the topology map. In IEEE 1394, since a child node declares a child node to a parent node, if the waiting time is long, the possibility of becoming a root node that is not after any node increases. Generally, a wait time sufficiently longer than a wait time for a bus reset of a printer, a color copier, a black-and-white digital copier, a scanner, or the like that is recognized in advance by the image controller is given to the IEEE1394 link controller of the image data controller. Must be set. This # 1
The determination as to whether the node is the root node 503 is repeatedly performed while increasing the wait time to some extent until the image controller becomes the root for the subsequent image data network management.

# 1505 When the image data controller is selected as the root node, each node on the network is asked for its attribute information.

# 1506 Then, a node attribute table is created from the attribute information returned from each node. This table describes whether to exchange image data with the image controller and, if data transfer is possible, the performance of the device. In the case of a printer, the presence / absence of one page memory, the resolution, the 1H time, the number of 1H pixels, the number of prints, and the like are included.

# 1507 Inquire the attribute information of each node to all nodes.

As described above, the attributes of all devices on the network are grasped after the topology map is created by the image controller, so that the overhead of command transfer at the time of data transfer is reduced.

<Tandem printing using printers having different resolutions> Next, regarding the transfer speed of IEEE 1394 in the items of the node attribute table, data transfer when the resolution of a plurality of transfer destination printers is different during tandem printing will be described. I do.

FIG. 32 is an attribute table created in step # 1506 of the flowchart in FIG. The image data controller 102 manages the devices connected to the image network based on the table. Each item of the table will be described. The node number is assigned to each node when the topology map is created. The transfer speed is a transfer speed supported by the IEEE 1394 physical interface, and is 400 Mbp.
s, 200 Mbps, and 100 Mbps. The power supply capability indicates whether the node can supply power via an IEEE 1394 cable. Also shown here is receiving power supply.

The device name indicates how the node transmits and receives image data to and from the image controller, or whether the node does not transmit and receive image data at all. If the device name is a scanner, it is an image data transmission device, and it is black and white / color, or the number of bits per pixel (bit / pixel), and the resolution (dp
Information such as i) is managed in a table. If the device name is a printer, it is an image data receiving device,
B / W / color, print output speed (ppm), bit /
There is information of pixel and dpi. If the device is a copier, it has both the functions of a scanner and a printer, so that information is managed as an image data transmitting / receiving device.

FIG. 33 shows each node on the image network shown in FIG.
05 is an attribute table of the monochrome digital copying machine 106.

Here, the tandem print is selected by the image data controller, and the monochrome printers 104 and 105 are selected.
Will be described with reference to the flowchart of FIG. # 3401 In the image data controller 102, tandem printing is selected, and a plurality of printers on the image network are selected. # 3402 In the image data controller 102, FIG.
Printers 104 and 105 are selected for tandem printing, and the information in their attribute tables is confirmed. # 3403 It is determined whether the resolutions of the printers used for tandem printing are all the same. In this example, the printer 104 has 600 dpi and the printer 105 has 400 dpi from the resolution of the attribute table information.
Proceed to 4. # 3404 It is determined whether or not a print used for tandem printing has a resolution conversion circuit. here,
The image data controller confirms whether or not a resolution conversion circuit exists in the printers 105 and 104 by asynchronous transfer. If both printers have no resolution conversion circuit as a result of the check, the process proceeds to step # 3409. If any of the printers has a resolution conversion circuit, the process proceeds to step # 3405. # 3405 # 340 if all printers used for tandem printing have a resolution conversion circuit
Proceed to 7. On the other hand, if the resolution conversion circuit does not exist in any of the printers, the flow advances to step # 3406 to create image data of the resolution of the printer. If there are a plurality of printers that do not have a resolution conversion circuit, one of them is selected based on the resolution, printing speed, and the like, and image data is created at the resolution of the printer. Printer 10
In the case of 4, 105, since the printer 105 does not have a resolution conversion circuit, image data of 400 dpi is created accordingly. # 3407 The image data controller 102 notifies the printer of the resolution of the image data by asynchronous transfer. The printer 104 having the resolution conversion circuit that has received this command prepares for resolution conversion from 400 to 600 dpi. Printer 10 without resolution conversion circuit
In step 5, the transmitted image data is printed as it is. # 3408 Tandem print data transfer is performed according to the data transfer flow of FIG.

If all the printers have a resolution conversion circuit in # 3405, the data is transferred using predetermined expanded data. Similarly, at step # 3407, the resolution information of the image data is sent to the printer, and based on the information, if the resolution conversion processing is required on the printer side, preparation is made.

# 3409 If no resolution conversion circuit exists in any printer, it is necessary to have image data in accordance with the resolution of the printer. For example, when the developed image data is 600 dpi, the image data controller performs a resolution conversion process in addition to the data, and
00 dpi image data is also created. 3410 Sends the resolution of image data to be transferred to each printer and the channel number in isochronous transfer of image data. In the # 3411 image data controller, a channel is secured and image data transfer is performed to perform individual isochronous transfer for each resolution.

If it is determined in step # 3403 that tandem printing is to be performed by a printer having the same resolution, the flow advances to step # 3407 to perform tandem printing in the same manner.

As described above, when performing tandem printing on printers having different resolutions, the image data controller determines the resolution of image data to be transferred during tandem printing based on the presence or absence of a resolution conversion circuit of each printer.

As described above, if all the printers used for tandem printing have the ability to print at the same resolution, or if at most one printer does not have a resolution conversion circuit, a printer without resolution By creating data with the matched resolution, the same image data can be efficiently transferred to all printers using isochronous transfer. In addition, if there are two or more printers having different resolutions from each other and having no resolution conversion circuit, image data having a resolution adapted to each printer is generated and transmitted individually, so that printing can be reliably performed by each printer. Can be made.

[Second Embodiment] In the first embodiment, in tandem printing, when the resolutions of a plurality of printers are different, the resolution of the image data to be transferred is determined by the presence or absence of a resolution conversion circuit. Explanation was given. However, the printer does not always have the resolution conversion circuit. Transferring image data at two different resolutions in accordance with the printer increases the traffic on the image network, and thus poses a problem if the data transfer requirements are not small. Therefore,
A case where tandem printing is realized by transferring image data having a higher resolution to two printers will be described.
When performing tandem printing on the printers 104 and 105 in FIG. 1, the resolution is 600 dpi for the printer 104 and 40 for the printer 105 as shown in FIG.
0 dpi. In the present embodiment, # 3409 in FIG.
To # 3408, that is, the processing when no resolution conversion circuit is provided in any of the printers.
3 is executed.

In step # 3501, the image data controller determines the resolution of the image data to be transferred to perform the tandem print from the information shown in FIG.

# 3502 The transmission of image data of 600 dpi to the printers 104 and 105 is transferred in the asynchronous transfer mode.

# 3503 Transfers 600 dpi image data in the isochronous transfer mode. At this time, the printer 104 receives the image data and performs the printing operation as it is. On the other hand, in the printer 105, the image data of 600 dpi is sent from the image data controller. Therefore, the received data is not printed as it is, but needs to be printed while thinning it. This operation is performed at the timing as shown in FIG.

In FIG. 36, image data WriteD
“ata” is data received by the 1394 interface of the printer 105. When this data is once written to the FIFO, the write enable signal is negated at a ratio of one pixel to three pixels with / WEN (write enable signal) as shown in the figure, whereby one pixel is thinned out of three pixels. Is done. Then, reading is controlled by / REN (read enable signal) and is continuously output, so that data equivalent to 400 dpi is printed.

In this embodiment, tandem printing is performed with high-resolution data. However, by transferring low-resolution data and repeatedly printing the same data on the high-resolution printer, the data is simply increased. Is also good. [Third Embodiment] In the first and second embodiments, the case where tandem printing is performed in printers having different resolutions has been described. However, in either case, the traffic increases when compared with the ideal data transfer time. Is inevitable. Therefore, tandem printing with printers having different resolutions may be prohibited. That is, among the printers connected to the image network managed by the image data controller, tandem printing is prohibited when at least two printers having the same resolution do not exist. If there are two or more, tandem printing is performed using those printers.

[0192]

[Other Embodiments] Even if the present invention is applied to a system including a plurality of devices (for example, a host computer, an interface device, a reader, a printer, etc.), an apparatus (for example, a copying machine) Machine, facsimile machine, etc.).

An object of the present invention is to provide a storage medium storing a program code of software for realizing the functions of the above-described embodiments to a system or apparatus, and to provide a computer (or CPU) of the system or apparatus.
Or MPU) reads and executes the program code stored in the storage medium.

In this case, the program code itself read from the storage medium realizes the functions of the above-described embodiment, and the storage medium storing the program code constitutes the present invention.

As a storage medium for supplying the program code, for example, a floppy disk, hard disk, optical disk, magneto-optical disk, CD-ROM, CD
-R, a magnetic tape, a nonvolatile memory card, a ROM, or the like can be used.

When the computer executes the readout program code, not only the functions of the above-described embodiment are realized, but also the OS (Operating System) running on the computer based on the instruction of the program code. ) Performs part or all of the actual processing, and the processing realizes the functions of the above-described embodiments.

Further, after the program code read from the storage medium is written into a memory provided in a function expansion board inserted into the computer or a function expansion unit connected to the computer, based on the instructions of the program code, The case where the CPU of the function expansion board or the function expansion unit performs part or all of the actual processing, and the function of the above-described embodiment is realized by the processing.

[0198]

As described above, the IEEE 13
When transferring a large amount of image data to a plurality of printers in the isochronous transfer mode of H.94, if the resolution of the transfer destination printer is different, if only one printer without a resolution conversion circuit is used, the resolution of the printer By transmitting image data, simultaneous data transfer becomes possible. Therefore, image data can be output from a plurality of printers without increasing network traffic.

If sufficient channels can be secured, tandem printing can be realized by securing channels for each resolution.

As described above, a large amount of data can be transferred without tightening the traffic of the network, and tandem printing is realized.

[Brief description of the drawings]

FIG. 1 is a diagram of an image network print system of the present invention.

FIG. 2 is a diagram showing a conventional office network.

FIG. 3 is a block diagram of an image data controller.

FIG. 4 is a flowchart of tandem printing.

FIG. 5 is a diagram of a printer designation screen from a PC.

FIG. 6 is a block diagram of a raster image development card.

FIG. 7 is a block diagram of a network interface card.

FIG. 8 is a block diagram of an image network interface card.

FIG. 9 is a block diagram of a printer.

FIG. 10 is a data transfer flowchart of commands and image data between an image data controller and a printer.

FIG. 11 is a flowchart of the image data controller when transferring image data.

FIG. 12 is a diagram showing a configuration of transfer data.

FIG. 13 is an operation timing chart on the printer side.

FIG. 14 is a flowchart of command and image data transfer between the image data controller and the printer during tandem printing.

FIG. 15 shows an IEEE1394 image data controller.
It is a flowchart of a bus initialization.

FIG. 16 is a diagram illustrating an example of a network configuration connected using a 1394 serial bus.

FIG. 17 is a diagram illustrating components of a 1394 serial bus.

FIG. 18 is a diagram showing an address map of a 1394 serial bus.

FIG. 19 is a sectional view of a 1394 serial bus cable.

FIG. 20 is a diagram for describing a DS-Link coding scheme.

FIG. 21 is a flowchart showing a flow from a bus reset to a determination of a node ID.

FIG. 22 is a flowchart showing the flow of parent-child relationship determination in a bus reset.

FIG. 23: after the parent-child relationship is determined in the bus reset,
It is a flowchart figure which shows the flow until a node ID is determined.

FIG. 24 is a diagram for explaining a topology setting for determining an ID of each node on a 1394 serial bus.

FIG. 25 is a diagram for explaining arbitration on a 1394 serial bus.

FIG. 26 is a flowchart for explaining arbitration.

FIG. 27 is a basic configuration diagram illustrating temporal state transition of asynchronous transfer.

FIG. 28 is a diagram illustrating an example of the format of an asynchronous transfer packet.

FIG. 29 is a basic configuration diagram showing a temporal state transition of isochronous transfer.

FIG. 30 is a diagram illustrating an example of a format of an isochronous transfer packet.

FIG. 31 is a diagram of an example of a bus cycle showing a state of a packet transferred on an actual bus in a 1394 serial bus.

FIG. 32 is a diagram of an attribute table created by the image data controller.

FIG. 33 is a diagram of an attribute table for each node on the image network.

FIG. 34 is a flowchart at the time of data transfer of the image data controller.

FIG. 35 is a flowchart at the time of data transfer of the image data controller.

FIG. 36 is a data thinning timing chart of the printer.

Claims (11)

[Claims] 1. A printing control apparatus connected to a plurality of printers and having a function of transmitting data to them at the same time, comprising: a comparison unit for acquiring and comparing output resolutions of the respective printers; If there is, a determination unit that determines whether there is a printer having a resolution conversion function; and if the determination unit determines that there is a printer that has a resolution conversion function, the determination unit determines whether the printer has a resolution conversion function. A print control apparatus comprising: a transmission unit that generates image data at a resolution and simultaneously transmits the image data to a printer corresponding to the resolution and a printer having a resolution conversion function. 2. The apparatus according to claim 1, wherein said transmission means further generates image data corresponding to each printer when there is no printer having a resolution conversion function, and transmits the image data to each printer. 3. The print control device according to claim 1. 3. The image processing apparatus according to claim 1, further comprising: when there is no printer having a resolution conversion function, generates image data corresponding to the highest resolution among the plurality of printers and transmits the image data to the plurality of printers simultaneously. The print control device according to claim 1, wherein: 4. If there is no printer having a resolution conversion function, the transmitting means generates image data only for printers having the same resolution with a resolution corresponding to those printers, and simultaneously transmits the image data to those printers. The print control device according to claim 1, wherein the print control device transmits the print request. 5. The printer according to claim 1, wherein the plurality of printers are IEEE13.
The print control apparatus according to claim 1, wherein the print control apparatus is connected by a communication path conforming to the 94 standard. 6. A printing control device connected to a plurality of printers and having a function of simultaneously transmitting data to the plurality of printers, comprising: a comparison step of acquiring and comparing output resolutions of the respective printers; In some cases, a determination step of determining whether there is a printer having a resolution conversion function, and when it is determined by the determination step that there is a printer having a resolution conversion function, the printer is adapted to one of the printers having no resolution conversion function. A method of generating image data at a resolution, and simultaneously transmitting the image data to a printer corresponding to the resolution and a printer having a resolution conversion function. 7. The transmitting step further includes, when there is no printer having a resolution conversion function, generating image data corresponding to each printer, and transmitting the image data to each printer. 3. The printing control method according to 1. 8. The transmitting step further includes, when there is no printer having a resolution conversion function, generating image data adapted to the highest resolution among the plurality of printers and transmitting the image data to the plurality of printers simultaneously. The print control method according to claim 6, wherein: 9. The transmitting step further includes, if there is no printer having a resolution conversion function, generating image data only for printers having the same resolution with a resolution corresponding to those printers, and simultaneously transmitting the image data to those printers. The print control method according to claim 6, wherein the print control is transmitted. 10. The plurality of printers are IEEE1
7. The print control method according to claim 6, wherein the print control method is connected by a communication path conforming to the 394 standard. 11. A computer connected to a plurality of printers and having a function of simultaneously transmitting data to the plurality of printers, a comparison means for acquiring and comparing output resolutions of the respective printers. Determining means for determining whether there is a printer having a function, and when the determining means determines that there is a printer having a resolution converting function, the image data is converted at a resolution corresponding to any one of the printers having no resolution converting function. A computer-readable storage medium storing a program for generating and functioning as a transmission unit for simultaneously transmitting image data to a printer corresponding to the resolution and a printer having a resolution conversion function.