JP2000293322A - Image forming system and transfer method - Google Patents

Abstract

(57) Abstract: In an image forming system connected via an IEEE 1394 serial bus, transfer of image data is efficiently performed to improve the bus utilization rate and to avoid loss of image data. When a user selects a device to be output and sets a transfer parameter, a transmitting device distributes image data of a predetermined number of lines to a selected receiving device by synchronous transfer, and receives image data. When the amount of data received is equal to the value set in the command register, the device transmits a line response packet to the transmitting device by asynchronous transfer, and the transmitting device returns line response packets from all devices selected by the user. At the point in time, transfer of the next image data by synchronous transfer is started, if transfer is completed normally, it will be the next image data transfer target, and when all image data has been transferred, transfer of predetermined image data will be started. Complete.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
A compound image forming apparatus, a printer, a personal computer, etc. having a four-interface communication function
The present invention relates to an image forming system and a transfer method for forming an image by transferring image data by being connected to a 1394 serial bus.

[0002]

2. Description of the Related Art In a conventional image forming apparatus, a composite type image forming apparatus in which a copying function is extended and a scanner function, a printer function, and a facsimile function are built in is mainly used. In addition, an embodiment has emerged in which the composite image forming apparatus is connected to another personal computer (hereinafter, referred to as a PC), a network printer, or a network server via a network to form one system.

A conventional means for connecting devices in such an image forming system is a network, that is, mainly Ethernet, and the connection protocol has generally been TCP / IP. However, in recent years, IEEE 1394 has been spotlighted as a means for connecting digital devices instead of this network.

[0004] The effects of using IEEE 1394 as a connection means instead of a network are various. A typical example is a transfer speed defined by IEEE 1394 and its transfer method.

[0005] The transfer method specified by IEEE 1394 is asynchronous transfer (asynchronous transfer) and isochronous transfer (synchronous transfer), and the transfer speed is 100M.
bps, 200 Mbps, and 400 Mbps are defined. In this standard, various communication protocols are devised based on these two transfer methods in order to connect various digital devices. At present, the connection protocol of the digital camera is determined, and the connection method of the printer to the IEEE 1394 serial bus is also being studied.

In view of the above, a plurality of composite image forming apparatuses,
In an image forming system in which a PC and a printer are connected via an IEEE 1394 serial bus, image data to be printed is transferred from a certain PC of the system or one image forming apparatus to another plurality of image forming apparatuses or a plurality of printers. It is possible to configure an image forming system for printing.

However, when Asynchronous transfer is used as the transfer method, the transmitting device must transfer the same image data to each receiving device based on the definition, and the bus utilization and the tandem printing operation are performed simultaneously. When using isochronous transfer (synchronous transfer), image data can be sent to all receiving devices at the same time, but the transmitting device should check whether the receiving device has correctly received the image data. Therefore, loss of image data during transfer is not allowed.

[0008]

As described above, a plurality of composite image forming apparatuses, PCs, and printers are required to be connected to the IEEE.
In an image forming system connected via a 1394 serial bus, image forming for transferring and printing image data to be printed from a certain PC or a certain image forming apparatus to another plurality of image forming apparatuses or a plurality of printers in a system. In the system, when Asynchronous transfer (asynchronous transfer) is used as the transfer method, the transmitting device must transfer the same image data to each receiving device because of its definition, which is inefficient, and the bus utilization, tandem printing operation, etc. It is not preferable from the viewpoint of synchronization, and when isochronous transfer (synchronous transfer) is used, image data can be sent to all the receiving devices at the same time, but the receiving device grasps whether the image data has been correctly received by the receiving device. There is no problem, and there is a problem that loss of image data during transfer is not allowed.

Therefore, the present invention can efficiently transfer image data in an image forming system connected via an IEEE 1394 serial bus, improve the bus utilization, and avoid image data loss. It is an object to provide an image forming system and a transfer method.

[0010]

An image forming system according to the present invention includes a plurality of devices including an image forming apparatus connected to a communication line in which a predetermined communication definition is defined. In the image forming system in which the device is formed, the device is assigned a number to all connected devices defined by the communication definition by turning on a device connected to the communication line, connecting a new device, or the like. In this case, the apparatus comprises a generating means for generating information corresponding to the unique number of the device and the assigned number, and a storage means for storing the corresponding information generated by the generating means.

An image forming system according to the present invention is an IEEE
In an image forming system configured by a plurality of devices including an image forming apparatus connected to a 1394 serial bus and transferring image data to form an image, the device includes:
When a bus reset peculiar to the IEEE 1394 occurs and numbers are determined for all the devices, generating means for generating information corresponding to the unique numbers of the devices and the determined numbers, and And storage means for storing correspondence information.

[0012] A transfer method of an image forming system according to the present invention comprises a plurality of devices including an image forming apparatus connected to a communication line capable of performing synchronous transfer and asynchronous transfer in which a predetermined communication definition is defined. Is a transfer method of an image forming system in which an image is formed by transferring the image data, wherein when the image data is simultaneously transferred from the device by designating one or more other devices, performing the synchronous transfer; Sending the image data reception response information from the designated device to the device that has transferred the image data, by performing the asynchronous transfer.

A transfer method for an image forming system according to the present invention comprises a plurality of devices including an image forming apparatus connected to an IEEE 1394 serial bus, and transfers image data to form an image by transferring image data. In the case where one or a plurality of other devices are designated and the image data is simultaneously transferred from the device, the IEEE1.
A step of performing synchronous transfer in a transfer method defined in IEEE 394, and a step of transmitting response information of receiving the image data from the specified device to a device that has transferred the image data, the transfer specified in the IEEE 1394. And performing asynchronous transfer in the system.

An image forming system according to the present invention includes an image forming apparatus connected to a communication line in which a predetermined communication definition is defined, and a plurality of devices including a personal computer, and transfers image data to form an image. In the image forming system, all of the devices have storage means for storing information on the device in which the predetermined communication definition is defined, and the device having a function of transmitting the image data corresponds to the other device. When the image data is transmitted to the other device, the information reading device reads out the information stored in the storage device of the other device via the communication line, and the display device displays the information read by the reading device. I have.

The image forming system according to the present invention is an IEEE
In an image forming system that includes an image forming apparatus connected to a 1394 serial bus and a plurality of devices including a personal computer, and in which image data is transferred to form an image, all of the devices are connected to the IEEE 1394.
Has storage means for storing information about the device in a unique address space defined in the, the device having a function of transmitting the image data, when transmitting image data to the other device, the other It comprises reading means for reading information stored in the storage means of the device via the IEEE 1394 serial bus, and display means for displaying the information read by the reading means.

A transfer method for an image forming system according to the present invention comprises a plurality of devices including an image forming apparatus connected to a communication line capable of synchronous transfer and asynchronous transfer, wherein a predetermined communication definition is defined, Is a transfer method of an image forming system in which an image is formed by transferring the image data, wherein when the image data is simultaneously transferred from the device by designating one or more other devices, performing the synchronous transfer; When transmitting the image data reception response information from the specified device to the device that has transferred the image data, performing the asynchronous transfer; and And a step of performing the asynchronous transfer when transferring the image data to the device again.

A transfer method for an image forming system according to the present invention comprises a plurality of devices including an image forming apparatus connected to an IEEE 1394 serial bus, and transfers image data to form an image. In the case where one or a plurality of other devices are designated and the image data is simultaneously transferred from the device, the IEEE1.
A step of performing synchronous transfer in a transfer method defined in IEEE 394, and a step of transmitting response information of receiving the image data from the specified device to a device that has transferred the image data, the transfer specified in the IEEE 1394. Performing the asynchronous transfer in the system, and transferring the image data again to the specified device to which the response information of the image data reception has not been transmitted.
Performing asynchronous transfer in the transfer method specified in 394.

[0018]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 schematically shows the entire configuration of an image forming apparatus according to the present invention. This image forming apparatus 1
Has a scanner 2 as image input means and a printer 3 as output means, and has an automatic document feeder (A
DF) 4 is attached.

The automatic document feeder 4 has a rear end edge of a cover body 21 as a housing, which is attached to a rear end edge of an upper surface of the apparatus main body via a hinge device (not shown) so as to be freely opened and closed. The configuration is such that the entire automatic document feeder 4 can be opened and closed to open the document table 5. A document table 22 capable of holding a plurality of documents collectively is provided on the upper surface of the cover main body 21 and slightly to the right. At one end of the apparatus, there is provided a feeder 23 for sequentially taking out documents one by one and supplying the originals to one end (left end in the figure) of the document table 5.

The feeding means 23 includes a pickup roller 27 for taking out a document, a weight plate 28 for pressing the document against the pickup roller, an empty sensor 29 as a document detection sensor for detecting a setting state of the document on the document feeder plate 22 and the like. Is arranged. Further, a paper feed roller 32 is arranged in the document take-out direction of the pickup roller 27 so that the documents are fed one by one reliably. A document conveying belt 37 covering the document table 5
Is stretched.

The original conveying belt 37 is a wide endless belt having a white outer surface stretched over a pair of belt rollers 40, 40, and is configured to be able to run in the forward and reverse directions by a belt driving mechanism (not shown). I have. A plurality of belt pressing rollers 41 for pressing the belt surface against the document table 5 and a set switch (not shown) for detecting the open / close state of the automatic document feeder are provided on the back side of the inner peripheral portion of the document conveying belt 37. Is provided. Then, the document fed by the feeding means 23 is transported from one end (left end) of the document table 5 to the other end (right end).

A paper discharging means 38 is provided at the right side of the apparatus, and the paper discharging means 38 includes a transport roller 44 and the transport roller 4.
4 is provided with a pinch roller 45 for pressing the document, a paper discharge sensor 46 as document detection means for detecting the rear end of the document sent in the paper discharge direction, and the like. A discharge roller 48 is provided downstream of the document discharge path. A gate 82 is provided in the document discharge path to guide the document upside down to the document table 5 so that the document can be copied on both sides.

The scanner 2 has an illumination lamp 6 as a light source,
A first carriage 7 on which a mirror 15 is installed, a second carriage 9 on which mirrors 8a and 8b for bending optical paths are installed, a lens 10, a CCD sensor 11 for receiving reflected light, and a drive system for changing the positions of these components (illustrated) No).

The first and second carriages 7 and 9 are connected to each other by a timing belt (not shown), and the second carriage 9 moves in the same direction at half the speed of the first carriage 7. It has become. Thus, scanning can be performed so that the optical path length to the lens 10 is constant. The lens 10 has a fixed focal length and is moved in the optical axis direction during zooming. In the CCD sensor 11, one pixel of the document corresponds to one image of the CCD sensor. The output of the CCD sensor 11 is output to an A / D conversion circuit described later.

First and second carriages 7, 9 and mirror 12
The movements of a and 12b are each performed by a stepping motor (not shown). The first,
The second carriages 7, 9 move in response to the operation of a timing belt (not shown) stretched between a drive pulley (not shown) and an idle pulley (not shown) connected to the rotation shaft of the stepping motor. It has become. The spiral shaft (not shown) of the lens 10 is rotated by a corresponding stepping motor (not shown), and is moved in the optical axis direction by the movement of the spiral.

Reference numeral 60 denotes a laser diode. A collimating lens 62, a polygon mirror (polyhedral reflecting mirror) 64, a lens 66, reflecting mirrors 68, 70, and a lens 72 are arranged corresponding to the laser diode 60. Is irradiated on the photosensitive drum 50.

The printer 3 combines, for example, a laser optical system and an electrophotographic system capable of forming an image on transfer paper. That is, the printer 3 has a photosensitive drum 50 rotatably supported at a substantially central portion in the apparatus, and an exposing device 52, a developing device 54, a transfer charger 55, and a peeling charger around the photosensitive drum 50. Reference numeral 56, a PCC charger 57, a static elimination lamp 58, and a charging charger 59 are arranged in this order.

The photosensitive drum 50 is uniformly charged by a charging charger 59 and outputs laser light from the scanner 2 to output the photosensitive drum 5.
An image of a document is formed on the top of the document. Then, the electrostatic latent image formed on the photosensitive drum 50 is developed by a developing device 54, and is fed from a paper feed cassette 30 as a paper feeding unit to be described later via a paper feeding roller 20 and an aligning roller 25. The transfer image is transferred by the transfer charger 55 onto the copy paper P to be transferred.

The copy paper P after transfer by the transfer charger 55 is peeled off by an AC corona discharge.
Then, the copy paper P on which the developed image is fused and fixed by the fixing device 71 is discharged to a unit 74 having a discharge tray 74a by a discharge roller pair 73. You. Unit 7
Reference numeral 4 denotes a pair of rollers 74b for face-down of the copy sheet P discharged from the pair of discharge rollers 73, and a stapler 74c for stapling one copy at a time in the staple sort mode above the unit 74. I have.

On the other hand, the developer remaining on the photosensitive drum 50 after the transfer and peeling of the developed image onto the copy paper P is PC
Charged by the C charger 57
As a result, the potential of the photosensitive drum 50 to the power of 50 can be reduced to a certain level or less, and the next copy operation can be performed.

In the case of double-sided copying for printing on both sides of the copy sheet P, the copy sheet P on which the developed image has been fused and fixed by the above-described fixing device 71 is conveyed through a conveyance path 75a and then accumulated on a tray 75b. Is done. This tray 7
The one-side printed copy paper P stored in 5b is conveyed to the above-described transfer charger 55 via the conveyance path 75c, and the developed image is transferred to the other side on which no printing is performed. A light reflection type paper sensor 75d is provided below the tray 75b.
Is provided on the tray 75b and the presence or absence of a sheet is detected.

An automatic double-side device (ADD) 75 as an automatic double-side reversing mechanism is constituted by the transport path 75a, the tray 75b, the transport path 75c, and the paper sensor 75d. In the drawing, reference numeral 30 denotes a paper feed cassette as a paper feed means which is detachably mounted on the upper side of the apparatus main body 1 in a detachable manner. The paper feed cassette 30 is composed of a cassette case 31 which is a housing in which copy paper P is stored, and has a configuration in which a take-out end of the cassette case 31 is inclined in a paper take-out direction. The copy paper P stored in the cassette case 31 of the paper feed cassette 30 is picked up from the uppermost layer by the pit 81 and taken out. The copy paper P taken out by the pickup roller 81 and sent to the take-out end of the cassette case 31 is supplied with a paper feed roller 84 and a separation roller ( Separation pad) 85
Is separated one by one by a paper separating section made of
It is designed to be transported toward.

FIG. 2 shows the configuration of a control system of the image forming apparatus 1 having a scanner, a printer, a facsimile, a network function, and an IEEE1394 interface according to the image forming apparatus system of the present invention.

In FIG. 2, an image forming apparatus 1 includes a CPU 100 for controlling the entire apparatus and a control panel 10.
3. CPU 106 for controlling the mechanical unit, image processing unit 10
7, bus controller 108, ROM 101, RAM 1
02, the IEEE 1394 interface 120 is connected via the control bus B1, and the CPU 100 controls them.

Further, the bus controller 108 includes a hard disk drive 110 and a facsimile
11, a page memory 112, and a network interface 130 are connected via a control bus B2. C
The PU 100 includes a bus controller 108, a control bus B2
, A hard disk (drive) 110, a facsimile transmission / reception unit 111, a page memory 112, and a network interface 130 are controlled.

The image processing unit 107 and the printer unit 10
5. Facsimile transmission / reception unit 111, page memory 112
Is configured to transfer image data via the image bus B3. Further, the image data can be transferred between the hard disk 110, the page memory 112, the facsimile transmission / reception unit 111, and the network interface 130 also on the control bus B2.

In addition, the scanner unit 104, the printer unit 105, the facsimile transmitting / receiving unit 11 of the composite image forming apparatus 1
1 can operate independently and individually.

The IEEE 1394 interface 120 is connected to an external IEEE 1394 serial bus 121.
And the network interface 130 is
It is connected to an external network 131.

Next, referring to FIG.
The detailed configuration of the image processing unit 107 will be described. The scanner CPU 4a of the scanner unit 104 includes a lamp control unit 4c for controlling the illumination lamp 4b, a scanning motor 4
d, a motor driver for controlling d, a sensor, a switch,
A driving unit 4g for driving and controlling a solenoid and the like is connected and controls these. The image processing unit 107 includes an A / D conversion circuit 7a, a resolution conversion circuit 7b, a shading correction circuit 7c, an image quality improvement circuit 7d, and a binarization circuit 7e for performing image processing on image data from the CCD sensor 11.
And performs image processing.

The image data read by the CCD sensor 11 is sent from the binarizing circuit 7e of the image processing unit 107 to the page memory 12 via the image bus B3, and is stored therein. I have.

Next, a detailed configuration of the printer unit 105 will be described with reference to FIG. The printer CPU 5a of the printer unit 105 includes a main motor driver 5c for driving the main motor 5b, a driving unit 5e for driving and controlling sensors, switches, and solenoids 5d, a fixing lamp control unit 5g for controlling the fixing lamp 5f, a charging charger. 5h,
High-voltage output control unit 5m for controlling transfer charger 5i, peeling charger 5j, PPC charger 5k, static elimination lamp control unit 5o for controlling static elimination lamp 5n, paper feed roller 5
p, paper feed controller 5s for controlling paper feed motor 5r for pickup roller 5q, light-to-light converter (laser diode)
5t, a laser driving circuit 5v for the polygon motor 5u is connected to a modulation circuit 5w for driving and controlled.

With the printer unit 105 having such a configuration, the image data sent from the page memory 112 via the image bus B3 is printed on a predetermined sheet under the control of the printer CPU 5a.

Next, a detailed configuration of the facsimile transmitting / receiving section 111 will be described with reference to FIG.

The facsimile CPU 111a of the facsimile transmission / reception unit 111 has a control bus interface (I /
F), an interface control circuit 111b including an image bus interface (I / F) unit, a memory (EPROM) 111c storing a control program, a memory (basic SRAM) 111d storing image data, and input / output. CODEC 111e for compressing and expanding image data
COD for compression and decompression when transmitting and receiving image data
EC 111f, NCU (Network Control Unit) 111 connected to a communication line and controlling, for example, a public line network
g, and a modem 111h that performs modulation and demodulation for transmitting and receiving data, and controls these.

Facsimile transmission / reception unit 1 having such a configuration
In step 11, the image data transmitted via the page memory 112 and the image bus B3 is subjected to processing such as compression and output to a communication line, and is also expanded to image data received via the communication line. After processing, image bus B3
, And is temporarily stored here.

The configuration of the page memory 112 will be described with reference to FIG.

The page memory 112 has a large number of DRAMs 112c for storing image data, and the SRAMs 11 for rotation processing.
2b, CODEC 112d is installed for compression and expansion,
These are all connected to the page memory controller 112a and are controlled by the page memory controller 112a. Also, the page memory controller 112
a is connected to both the control bus B2 and the image bus B3, and also arbitrates access to the page memory 112 via the control bus B2 and the image bus B3.

Image processing such as compression, decompression, rotation, and synthesis for image data on the page memory 112 is performed by the CPU.
100 by controlling the page memory controller 112a via the bus controller 108 and the control bus B2.

The image data on the page memory 112 can be accessed from either the control bus B2 or the image bus B3, and the arbitration work of the access is performed by the page memory controller 112a.

Next, the IEEE 1394 interface 120 will be described with reference to FIG. IEEE13
The 94 interface 120 is a LINK chip 120
a and a PHY chip 120b. The LINK chip 120a is connected to the CPU via the bus B1.
100, and the LINK chip 120a and the PHY chip 120b are connected by an interface IF1 defined by IEEE1394. This IE
P used in the EE1394 interface 120
The HY chip 120b has three ports (port A, port B,
It is a port C) type and has three connection ports to the IEEE1394 serial bus 121.

The function of each chip is as follows.
The chip 120b converts the data received from the LINK chip 120a into serial data, and performs IEEE conversion at a predetermined speed.
1394 serial bus 121, IEEE 139
4 Received from the serial bus 121. One of the main roles is to detect a bus reset and activate a sequence for determining a node number. The LINK chip 120a has an interface between the CPU 100 and the PHY chip 120b. Its main role is to control asynchronous and synchronous transfer and notify the CPU 100 of an interrupt.

This interface can be used in common for each device in the image forming system of the present invention, and has the same configuration.

In recent years, a standard called IEEE 1394 for connecting digital devices and transferring digital data is being determined. The IEEE 1394 connects devices via a serial bus, and transfers data between devices at a standard-determined speed. On the serial bus, the device is a node (Nod
The distinction of nodes expressed as e) is performed by unique node numbers.

The data exchanged on the serial bus is, of course, bit string data. In IEEE 1394, this bit string is collected into a certain unit as a packet, and the node outputs the packet to the serial bus. In addition, information relating to transfer called a header is added to the data block called a packet in addition to data to be transferred between nodes.

The node number described in the header is IEEE
After a bus reset specified by E1394 occurs, the number is uniquely determined for each node on the serial bus by a predetermined procedure. Each node uses this node number for data transfer.

The header also describes information called an address. Regarding the use of this address space,
It is standardized by EE1394, and the purpose of use, the area unique to the node, and the like are determined.

In IEEE 1394, two transfer systems are defined.

First, the asynchronous transfer will be described with reference to FIG. Asynchronous transfer starts when a node that wants to transfer data acquires a bus.

A node that wants to transfer data by arbitration in FIG. 8 issues a request to the serial bus. The node that wins the arbitration has the right to occupy the bus. The node having the bus occupation right is shown in FIG.
A data packet (hereinafter, asynchronous packet) having the data structure shown in (1) is output to the bus at a predetermined communication speed.

The packets include (a) and (b) in FIG.
As shown in FIG. 7, information such as information on a destination node and a source node of data and an address unique to the destination node are added as a header.

[0062] The receiving node recognizes that the receiving node is the target of receiving from the information included in the header, and recognizes from which node this data was transmitted from the node information of the transmission source of the header.

When the receiving node receives the asynchronous packet, the receiving node then transmits to the node that transmitted the data an Ac packet having the configuration shown in FIGS. 10A and 10B.
knowledge packet (hereinafter referred to as approval packet)
Reply.

The acknowledgment packet contains information called an acknowledgment code, and the transmitting node of the data receiving the acknowledgment packet recognizes whether the transferred data has been normally received. As described above, the operation in which one authentication packet is returned in response to one asynchronous packet transmission ensures the security of the transferred data in the asynchronous transfer.

Next, the isochronous transfer (hereinafter referred to as asynchronous transfer) will be described with reference to FIG.

In the asynchronous transfer, a node that wants to transfer data issues a request to the bus. The node that wins the arbitration in FIG. 11 has the bus occupation right.

The node having the bus occupation right outputs a data packet having a data structure shown in FIGS. 12A and 12B (hereinafter referred to as a synchronous packet) to the bus at a predetermined communication speed. I do. As shown in FIG.
A header containing the channel number used by the transmitting node as information is added to this synchronization packet.

The receiving node determines whether or not the data is to be received based on the channel number in the header, and determines the data fetch.

The synchronous transfer differs from the asynchronous transfer in that the receiving node does not send an acknowledgment packet back to the data transmitting node. That is, in this synchronous transfer, the integrity of the received data is the responsibility of the receiving node, and when the receiving node receives a synchronization packet, some trouble or the like occurs, and even if the synchronization node fails to receive the synchronization packet, the transmission node does not know.

Further, there is a difference in the time required for arbitration between the asynchronous transfer and the synchronous transfer in FIGS. 9 and 11, so that the synchronous transfer has an advantage of bus acquisition as compared with the asynchronous transfer. That is, this means that the synchronous transfer can always secure a constant data transfer rate to the bus. This is an advantage of transferring data by synchronous transfer.

However, the synchronous transfer does not always have an advantage over the use of the serial bus as compared with the asynchronous transfer.
According to the E1394 standard, synchronous transfer is 8 times the bandwidth of the serial bus.
Use up to 0% and an upper limit.

FIG. 13 shows the configuration of an image forming system according to the present invention. According to the image forming system of the present invention, a plurality of image forming apparatuses (A, B, C), printers (A, B), and PCs (1, 2) have an IEEE 1394 interface 120 shown in FIG.
And is connected to the IEEE 1394 serial bus 121 via a USB port.

In the IEEE 1394 standard, when a device is turned on or a new device is added to the serial bus, a bus reset occurs in the serial bus. By this bus reset, each device in the system, ie, IEEE 1394, determines a node number unique to the node by a predetermined procedure. The serial bus uses this node number to generate an address on the serial bus and to transfer data between nodes.

However, this standardized IEEE
The use of only the 1394 transfer management method may cause inconvenience in the image forming system having the configuration shown in FIG.

Although the method of determining the node number specified by IEEE 1394 is a mechanism in which a unique number is allocated to each node, the node number allocated after the bus reset occurs is the same as the node number before the bus reset occurs. Is not guaranteed to be. Of course, even if the node number changes, there is no problem in the data transfer itself specified by IEEE1394.

However, the image forming system shown in FIG. 13 handles data transfer in stationary devices such as an image forming apparatus, a PC, and a printer. It will be very important to obtain.

For this reason, if data transfer is managed solely because the node number is uniquely determined for a node, there is a possibility that data may be transmitted to a different device after a bus reset. There is. In order to avoid this, a control method of the present invention for managing the system device and the node number in pairs will be described below.

The equipment (image forming apparatus, printer, PC, etc.) in the image forming system of the present invention is an IEEE 13
FIG. 1 shows the node-specific address space defined in FIG.
A register group 200 having information on the devices shown in FIG.

The register group 200 shown in FIG. 14 will be described.

The first field contains the identifier of the register group 200, and if this register is present, supports the transfer protocol of the present invention.

The second field stores a device code indicating what the device is.

In the third and fourth fields, device-specific numbers are described.

The fifth field describes the size of received data that can be continuously received by the device. This size reflects the size of the line buffer and page buffer of the device.

In the sixth field, there is a register for writing the line response packet and the page response packet of the present invention. This register is not used when the device having the register group 200 becomes a data receiving device. However, when the device becomes a transmitting device, a line response packet,
The contents of the page response packet are written to this register.

The seventh field stores a value indicating the number of prints per minute of the device.

The eighth field describes the type of paper that can be printed by the device.

The ninth field describes the location of a register at which a command for the device can be issued.

The tenth field describes the location of a register from which the status of the device can be grasped.

The eleventh field is a reserved field for the future.

In the twelfth field and thereafter, the device name and the installation location of the device are stored as character strings.

By reading these registers from another device via the IEEE 1394 serial bus 121, the read device recognizes that the device supports the protocol of the present invention and can obtain information on the device. it can.

By accessing the command register located at the location indicated by the ninth field in FIG. 14, the device can also be controlled, and the status information of the device located at the location indicated by the tenth field can be used. It is also possible to know the current state of the device.

In the data transfer protocol of the present invention, when a bus reset occurs and the node number is updated,
All devices that can transfer image data after determining a new node number access the above registers of all devices of this system to obtain device-specific information.

Then, the correspondence between the device-specific number obtained from the register and the node number assigned to the device is obtained, and the correspondence list of the device node numbers is shown in FIG.
Create as shown.

In the list shown in FIG. 15, the field of the device unique number is 0x00000000 or 0xFFFF.
FFFF is a register group 200 defined in FIG.
Means that the device corresponding to the node number does not support the protocol of the present invention.

As described above, according to the protocol of the present invention, the data transfer between the devices is managed by the device unique number, and the device refers to this list at the time of the data transfer.
It is characterized in that the device unique number is converted into a node number defined in IEEE 1394 and data is transferred.

The device-specific information in the image forming system obtained as described above is stored in the user interface of the image data transmitting device, ie, the image forming devices (A, B,
In the case of (C), the control panel is used, and in the case of the PC (1, 2), the information is displayed and symbolized as an icon on a display means such as a display.

Next, the transfer protocol in tandem of the present invention will be described.

As described above, IEEE 1394 defines two types of transfer methods, asynchronous transfer and synchronous transfer. Examples of data transfer applications using the advantages of each of these transfer methods include transfer in which data must not be lost in asynchronous transfer, and transfer in which data transfer bandwidth must not be reduced in synchronous transfer.

Specifically, the former is used for transferring image data of a printer or the like, which must not be lost, and the latter has no problem on the viewer side even if one frame of video such as digital TV is lost. Rather, the transfer method is suitable for a system in which a failure occurs due to a decrease in the transfer band.

Usually, a system is constituted by an image forming apparatus,
When IEEE 1394 is used for data transfer between these devices, the former asynchronous transfer is used in the same manner as the printer, because of the nature of the image data and the advantages of the transfer.

However, when a communication protocol is constituted only by this asynchronous transfer in so-called tandem printing in which there are a plurality of print output destinations as in the present invention, the IEEE 1394 asynchronous transfer specification is applied to a device to be printed out. Therefore, asynchronous packet transmission and acknowledgment packet exchange occur between the devices on a one-to-one basis. If this asynchronous transfer method is used for tandem printing in such a configuration, there will be a difference in the time until image data to be printed arrives at each print output destination, and in a narrow sense, tandem printing cannot be said.

In addition, the same data is sequentially transmitted to each output destination, and the same image data is exchanged by the number of output destinations on the serial bus, so that the bus use efficiency is clearly reduced. Will be done.

In such a case, a transfer method capable of simultaneously transmitting data to each printing destination, that is, synchronous transfer is more suitable for the advantage of the transfer. However, as described above, in the synchronous transfer, even if the printing destination device, that is, the receiving node misses the data for some reason, the transmitting source node has no way of knowing.

Therefore, in the present invention, the page response packet (pa
ge acknowledge packet: PAGE_ACK and line acknowledge packet: LINE_AC
K).

The data fields of the page response packet and the line response packet have a structure as shown in FIG. That is, in FIG. 16, bit 31 is a distinction between a page response packet and a line response packet.
Bits 16 to 27 code and represent the error detected on the receiving device side. Bit 0 to bit 1
Reference numeral 5 indicates the number of page response packets or line response packets in the number of transfers.

These packets have a logical structure indicating that they are asynchronous transfer packets and are received by the device that prints the image of the specified number of lines or the specified number of pages.

The receiving device is the same as the register group 2 of the transmitting device.
The value of this data field is written asynchronously to the page and line authentication packet reception register at offset 14H of 00.

Except for the failure of physical data transfer on the receiving path, data receiving errors often occur when the receiving side misses received data by synchronous transfer.

This problem can be solved by a transfer protocol which introduces a page authentication packet and a line authentication packet as shown in FIGS.

In FIG. 17A, the transmitting device (No.
de1) transmits the image data on the channel specified by the synchronous transfer (Isochronous transfer). In the figure, image data “ISO1”, [ISO2], “ISO3”. On the other hand, each of the receiving-side devices (Node 2 and Node 3) that have received the image data performs asynchronous transfer (Asynchro
Nous transfer), “LINE_ACK”, which is a mark that completely received the image data, is transmitted to the transmitting device, and the transmitting device (Node 1) returns an “ACK” response to each. Then, the transmitting device (Node 1) starts synchronous transfer of the next data.

In FIG. 17B, the transmitting device (No.
de1) is the image data “ISO1” and “ISO” on the channel designated by the synchronous transfer (Isochronous transfer).
2 "and" ISO3 ". On the other hand, the receiving device (Node 2) that has received the image data transmits “LINE_ACK” to the transmitting device by asynchronous transfer (Asynchronous transfer), and the transmitting device (Node 1) returns an “ACK” response. Further, the transmitting device (Node 1) transmits the image data “ISO4”, “ISO5”, “ISO” on the channel specified by the synchronous transfer (Isochronous transfer).
(The data transfer for the page to the receiving device Node3 is completed), the receiving device (Node2) transmits "LINE_ACK" to the transmitting device by asynchronous transfer (Asynchronous transfer), and the transmitting device (Node1) transmits An “ACK” response is returned, and the receiving device (Node 3) performs the asynchronous transfer (Asyn
“PAGE_ACK” is transmitted to the transmitting device by chronous transfer), and the transmitting device (Node 1) returns an “ACK” response.

Next, the transfer operation of the image forming system in such a configuration will be described with reference to the flowcharts of FIGS.

First, the IEEE 1394 serial bus 12
1 (ST1), when the image data is not being transferred (ST2), each device of the image forming system (image forming apparatuses A, B, C, printers A, B, PC1, PC1, A new node number is allocated to 2) (ST3).

Subsequently, the transmitting device that supports the protocol accesses the registers of all the devices in the image forming system, and based on the information obtained here, the device-specific number corresponds to the node number at that time. The created list is created (generated) (ST4).

The obtained information is displayed on the display means of the transmitting device of the image forming system, that is, the image forming apparatus (A,
Control panel, PC not shown for B, C)
If (1, 2), it is symbolized and displayed as an icon on a user interface such as a display (not shown) (ST5).

When the user performs tandem printing, the user selects an output device symbolized on the user interface of the image forming apparatus (A, B, C) or the PC (1, 2) (ST6).

When the user selects a device to output, the device that transmits image data sends the amount of data to the command register of the device selected as the output destination by the channel for transmitting image data, the transfer speed, and the synchronous transfer. Then, the transfer parameters such as are set (ST7). In addition,
The amount of data to be sent in the synchronous transfer is determined according to the smallest receiving buffer among the devices selected by the user as the output device.

When the reception buffer of the device that performs print output has an amount of one or more pages, the device that transmits image data requests the command register of the receiving device to reply with a page response packet. This page response packet operation will be described later.

Normally, a response from a device receiving the protocol of the present invention expects a line response packet. The line response packet is transmitted to the image data transmitting device when the received data becomes equal to the transfer data amount set in the command register at this time.

When the setting in the command register is completed and the data transfer from the user interface is started, such as when the user presses the copy start button, the transmission of image data is started by synchronous transfer (ST11).

The transmitting device confirms to which device the image data is to be transmitted. At this time, the transmitting device also knows which device returns the line response packet and which device returns the page response packet (ST12). Are distributed to the receiving device selected by the synchronous transfer (ST13).

When the amount of received data is equal to the value set in the command register, the receiving device that receives the image data transmits a line response packet to the transmitting device by asynchronous transfer.

When the line response packets are returned from all the devices selected by the user, the transmitting device of the image data starts transferring the next image data by synchronous transfer (ST).
16, 17).

If the receiving device does not return a line response packet by asynchronous transfer even after a certain period of time has passed (ST14), or if a line response packet (ST15) indicating an error is transmitted, Enter the data retransmission sequence.

The transmitting device knows the location of the status register of the receiving device in the above exchange. If the transmitting device detects any occurrence of an error in the receiving device, the cause of the error can be specified by reading the status register (ST21).

This status information describes the current state of the device. If the error is an authentication packet error or a transfer time-out (ST22), or if an unrecoverable error has occurred (ST23), the status of the device thereafter. The transfer to is stopped, and a message to that effect is displayed on the user interface (ST27, ST28).

However, in the case of any other error, the image data is again asynchronously transmitted to the address of the reception buffer indicated in the status register (ST2).
4).

In the present invention, since the asynchronous transfer is used in the retransmission sequence, the security of the data content at the time of data retransmission is maintained.

If a transfer error occurs here (ST
25) In the same manner as above, the fact is displayed on the user interface, and the subsequent data transfer to the device is stopped (ST27, ST28).

If the transfer is completed normally, the next image data is to be transferred (ST26), and step ST26 is executed.
Move to 16.

The operations of steps ST12 to ST17 are repeated, and when all the image data have been transferred (ST17), the transfer of the predetermined image data is completed.

Next, a case where a page response packet in this transfer protocol is returned from the receiving device will be described.

When the receiving device has a receiving buffer having one or more pages and the transmitting device makes a response request by the page response packet through the command register, the requesting device transmits the data by the synchronous transfer specified by the command register. When the amount of received data has been reached, the device does not return a line response packet to the transmitting device. Instead, a page response packet is returned to the transmitting device when the received data reaches one page.

First, the transfer source device synchronously transfers the image data for the number of lines determined in the above-mentioned exchange to the I / O line.
Data is output onto the IEEE 1394 serial bus 121.

The receiving device receives image data from the IEEE 1394 serial bus 121.

Here, the receiving device which has to return the line response packet determined by the setting in the command register described above transmits the line response packet to the transmitting device by asynchronous transfer.

Since the transmitting device knows from which device the line response packet returns, it waits for the start of the synchronous transfer of the next line data until the line response packet is returned from all those devices.

If there is a device that does not return a line authentication packet even after a certain period of time or a device that returns line authentication but indicates that an error has occurred, the status information of the device that has reported the error is read out.

If an unrecoverable error status is indicated, the subsequent data transfer to the device is stopped, and the fact is displayed on the user interface.

If the status is other than an unrecoverable error status, the present protocol retransmits the image data to the device in which the error has occurred by asynchronous transfer.

If an error occurs during the asynchronous transfer at the time of retransmission, the subsequent data transfer to the device is stopped, and the fact is displayed on the user interface.

The device that returns these page response packets repeats these operations, and when one page of image data is received in the page buffer of the receiving device, returns the page response packet to the image data transmitting device.

If there is a node that does not return a page response packet for a predetermined transfer amount, the status register of a device that does not return a page response packet as in the case of the line response packet is read, and an unrecoverable error occurs. If so, the transfer of the image data to the device thereafter is stopped, and the fact is displayed on the user interface.

If the error is an error other than an unrecoverable error, data is transferred again to this device by asynchronous transfer.

If an error occurs during the asynchronous transfer, the subsequent data transfer to the device is stopped and the fact is displayed on the user interface.

This operation is repeated. Then, the transfer of the predetermined image data ends.

In the above-described line response packet protocol, a line response packet is returned from all the receiving devices for one line data transfer of an image.

On the other hand, this page response packet is applied to a receiving device having a large receiving buffer, and the page response packet is returned to the transmitting node only after receiving data for a page. As a result, the use of the bus by the response from the receiving device can be suppressed,
There is an advantage that leads to a reduction in bus utilization.

Next, error recovery when a transfer error occurs in the transfer protocol of the present invention will be described with reference to the flowcharts of FIGS.

In the transfer protocol of the present invention in which the synchronous transfer and the asynchronous transfer are mixed, the occurrence of an error at the time of image data transfer is recognized when a page response packet or a line response packet is not returned from the receiving device or when a new device is used. Added to the IEEE 1394 serial bus 121,
It can be detected when a bus reset defined in IEEE1394 occurs.

The action to be taken when a line response packet and a page response packet are not returned from the receiving device has already been described.

Here, the protocol handling of the present invention when a bus reset occurs during image data transmission will be described.

In the protocol of the present invention, the data security is confirmed by returning a line response packet and a page response packet from the receiving device to the transmitting device, and the transmitting device grasps the data security. .

That is, when a bus reset occurs during the image data transfer by the synchronous transfer, the receiving device guarantees at least the data security up to the point where the line response packet and the page response packet are returned.

Here, the operation when a bus reset occurs during data transmission will be described with reference to the flowchart in FIG.

When detecting the occurrence of a bus reset, the transmitting device immediately stops transmitting image data by synchronous transfer (ST31).

Since a bus reset has occurred, all the devices of the image forming system immediately shift to the node number determination sequence defined by IEEE 1394, and new node numbers are determined for all nodes (ST3).
2).

A transmitting device that supports the protocol of the present invention in the present image forming system must create a list of node numbers and device-specific numbers. For this purpose, the register is read out by asynchronous transfer via the IEEE 1394 serial bus 121, and a correspondence list is created (ST33).

Since the transfer destination of this protocol is managed by this list, the image data transmitted at the time of the bus reset is again synchronized with the receiving device designated by tandem printing before the bus reset occurs. It is retransmitted by transfer (ST34).

Referring to the flow chart of FIG. 22, the operation when a bus reset occurs before a line / page response packet is returned from the receiving device and a line / page response packet is received from another node. explain.

When a bus reset occurs, the transmitting device records from which reception the line response packet or page response packet has not been returned (ST41), and the IE
All devices in the system immediately shift to the node number determination sequence defined by EE1394 (ST4).
2).

In this system, in order to create a list of node numbers and device-specific numbers, a transmitting device that supports this protocol reads the register by asynchronous transfer via the IEEE 1394 serial bus 121 and creates a correspondence list (ST43). ).

Since the transmitting device knows from which reception the line response packet or page response packet has not been returned, the transmitting device asynchronously transfers the bus reset to the node that does not respond in the same manner as when the error occurred. The same data as the data sent before the occurrence is transferred (ST4).
4).

If there is an authentication packet error or a transfer timeout (ST45), transmission of image data to the device thereafter is stopped (ST46), and the receiving device has a fatal error. Is displayed on the user interface (ST47).

If there is no authentication packet error or transfer timeout (ST45), when the transmission node grasps that the line response packet and the page response packet have been returned from all the predetermined nodes, the transmitting node starts synchronous transfer of the next data. (Transfer to ST12).

As described above, according to the embodiment of the present invention, by introducing the page response packet and the line response packet, the transmitting device can grasp the image data reception error even when the synchronous transfer method is used. be able to.

When an error occurs, the transmitting device
Since asynchronous transfer is used in the retransmission sequence, security of the image data at the time of retransmitting the image data can be ensured.

In addition, the page response packet in response to the line response packet,
Since the page response packet is returned to the transmitting device, the usage rate of the serial bus can be reduced.

Further, even if a bus reset defined in IEEE 1394 occurs during the transfer of image data, it is possible to prevent a failure from occurring in subsequent image data transfer.

[0171]

As described in detail above, according to the present invention,
Provided is an image forming system and a transfer method capable of efficiently transferring image data in an image forming system connected via an IEEE 1394 serial bus, improving a bus utilization rate, and avoiding loss of image data. be able to.

[Brief description of the drawings]

FIG. 1 is a diagram schematically showing an entire configuration of an image forming apparatus according to the present invention.

FIG. 2 is a diagram showing a configuration of a control system related to the image forming apparatus system of the present invention.

FIG. 3 is a diagram illustrating a configuration of a scanner unit and an image processing unit.

FIG. 4 is a diagram illustrating a configuration of a printer unit.

FIG. 5 is a diagram showing a configuration of a facsimile transmission / reception unit.

FIG. 6 is a diagram showing a configuration of a page memory.

FIG. 7 is a view for explaining an IEEE 1394 interface.

FIG. 8 is a diagram for explaining asynchronous transfer.

FIG. 9 is a diagram for explaining a data packet (asynchronous packet).

FIG. 10 is a diagram for explaining an Acknowledge packet (acknowledge packet).

FIG. 11 is a diagram illustrating isochronous transfer (asynchronous transfer).

FIG. 12 is a diagram for explaining a data packet (synchronous packet).

FIG. 13 is a configuration diagram showing a configuration of an image forming system according to the present invention.

FIG. 14 is a diagram illustrating a register group;

FIG. 15 is a diagram showing a correspondence list of device numbers and node numbers.

FIG. 16 is a diagram for explaining a page response packet and a line response packet.

FIG. 17 is a diagram for explaining a transfer protocol in which a page authentication packet and a line authentication packet are introduced.

FIG. 18 is a flowchart illustrating a transfer operation of the image forming system.

FIG. 19 is a flowchart illustrating a transfer operation of the image forming system.

FIG. 20 is a flowchart illustrating a transfer operation of the image forming system.

FIG. 21 is a flowchart for explaining an error recovery operation when a transfer error occurs in a transfer protocol.

FIG. 22 is a flowchart for explaining an error recovery operation when a transfer error occurs in a transfer protocol.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Image forming apparatus 100 ... CPU 101 ... ROM 102 ... RAM 104 ... Scanner part 105 ... Printer part 107 ... Image processing part 112 ... Page memory 120 ... IEEE1394 interface 121 ... IEEE1394 serial bus (communication line)

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H04N 1/00 H04L 11/00 320 5K033 F term (Reference) 2C061 AP01 AP03 AP07 AQ06 AR03 HQ01 HQ20 5B021 BB00 EE01 MM01 NN06 5B077 AA03 AA24 AA32 AA41 FF12 5C062 AA05 AA35 AB16 AB22 AB23 AB42 AB53 AC43 AF00 BA00 5K032 DB19 DB22 DB31 EC01 EC02 EC04 5K033 DB12 DB14 DB25 EC01 EC02 EC04

Claims (8)

[Claims] 1. An image forming system comprising a plurality of devices including an image forming apparatus connected to a communication line in which a predetermined communication definition is defined, wherein image data is transferred to form an image. When a number is given to all connected devices defined in the communication definition by turning on the power of the device connected to the communication line, connecting a new device, etc., An image forming system, comprising: a generation unit that generates information corresponding to a number that has been assigned, and a storage unit that stores the correspondence information generated by the generation unit. 2. An image forming system comprising a plurality of devices including an image forming apparatus connected to an IEEE 1394 serial bus, wherein image data is transferred to form an image, wherein the device is a bus reset specific to the IEEE 1394. Is generated, and when the numbers are determined for all the devices, generating means for generating information in which the unique numbers of the devices correspond to the determined numbers, and storage for storing the correspondence information generated by the generating means And an image forming system. 3. A plurality of devices including an image forming apparatus connected to a communication line capable of synchronous transfer and asynchronous transfer in which a predetermined communication definition is defined, and image data is transferred to form an image. A transfer method of an image forming system, comprising: performing synchronous transmission when simultaneously specifying one or more other devices from the device and performing image data transfer; and transmitting the image data from the specified device. Transmitting the image data reception response information to the device that has transmitted the image data by the asynchronous transfer. 4. A method for transferring an image forming system comprising a plurality of devices including an image forming apparatus connected to an IEEE 1394 serial bus, wherein image data is transferred to form an image, wherein the device includes another device. When simultaneously transferring image data by designating one or a plurality of devices, performing synchronous transfer in the transfer method defined by the IEEE 1394; and transferring the image data from the designated device to the device that has transferred the image data. When transmitting the response information of the image data reception,
Performing an asynchronous transfer in a transfer method defined in EEE1394, and a transfer method for the image forming system. 5. An image forming system, comprising: an image forming apparatus connected to a communication line defined by a predetermined communication definition; and a plurality of devices including a personal computer, wherein image data is transferred to form an image. All the devices have storage means for storing information on the device in which the predetermined communication definition is defined, and a device having a function of transmitting the image data transmits image data to the other device. An image characterized by comprising: reading means for reading information stored in the storage means of the other device via the communication line; and display means for displaying the information read by the reading means. Forming system. 6. An image forming system comprising an image forming apparatus connected to an IEEE 1394 serial bus and a plurality of devices including a personal computer, wherein image data is transferred to form an image, wherein all of the devices are: When a device having a storage means for storing information on the device in a unique address space defined by IEEE 1394 and having a function of transmitting the image data transmits the image data to the other device, The information stored in the storage means of the other device is stored in the IEEE 139
(4) An image forming system, comprising: reading means for reading via a serial bus; and display means for displaying information read by the reading means. 7. A plurality of devices including an image forming apparatus connected to a communication line capable of synchronous transfer and asynchronous transfer in which a predetermined communication definition is defined, and image data is transferred to form an image. A transfer method of an image forming system, comprising: performing a synchronous transfer when simultaneously specifying one or more other devices from the device and transferring the image data; and transmitting the image data from the specified device. Transmitting the image data reception response information to the device that transferred the image data, performing the asynchronous transfer, and transmitting the image data again to the specified device to which the image data reception response information was not transmitted. Wherein the transfer is performed by the asynchronous transfer. 8. A transfer method for an image forming system, comprising a plurality of devices including an image forming apparatus connected to an IEEE 1394 serial bus, wherein image data is transferred to form an image. When simultaneously transferring image data by designating one or a plurality of devices, performing synchronous transfer in the transfer method defined by the IEEE 1394; and transferring the image data from the designated device to the device that has transferred the image data. When transmitting the response information of the image data reception,
A step of performing asynchronous transfer in a transfer method defined by IEEE 1394; and a step of transferring the image data again to the specified device to which the response information of the image data reception has not been transmitted is defined by the IEEE 1394. A method of performing asynchronous transfer in a transfer method, the method comprising: