JP2001086132A - Communication system, print system, communication method and print control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To properly send/receive data between devices being components of a network. SOLUTION: Occurrence of a bus reset in an IEEE 1394 during data transfer between a device transmitting print data and a device processing the print data, reconfiguration of buses is detected (S408), and the transfer of the print data is temporarily interrupted on the basis of the result of detection (S414). Whether or not the interrupted transfer of the print data is restarted is discriminated by comparing a node ID given to each device node on the basis of the network configuration with a unique ID of each device given independently of the network configuration before and after the bus reset (S414, S412).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication system in which a plurality of communication devices for reconfiguring a communication configuration of a communication system are connected. Communications system,
The present invention relates to a printing system and a method thereof.

[0002]

2. Description of the Related Art As a conventional example, a communication system using an IEEE 1394 interface will be described. I
In a device connected to the IEEE 1394 interface, when a bus reset occurs for some reason and communication on the network is interrupted, communication interruption is resumed as follows.

[0005] The cause of the occurrence of the bus reset and the reconfiguration of the communication system is that, for example, a new connection device is connected to a node, issues a bus reset, and the node number is reassigned. In such cases,
When the connected device itself is reset, the communication unit of the device is reset, and a case where a bus reset is issued to reconnect to the communication system may be considered.

When a bus reset is performed between devices connected by the IEEE1394 interface, a bus is reconfigured. Since the node ID may change in each connected device due to the reconfiguration of the bus, each connected device reads the unique ID recorded on the unique ROM of the device connected to the bus, and reads the unique ID on the network. The correspondence between the node ID and its unique ID is stored.

When the bus reset is performed, each connected device reads the unique ID recorded on the unique ROM of the device connected to the bus again, and records and recognizes a new correspondence with the node ID. As a result, even if the communication with the connected device that is communicating before the bus reset is in progress and the node ID changes due to the bus reset, the new node ID of the connected device that is currently communicating is recognized by the unique ID. Communication can be resumed.

[0006]

However, such a conventional system has the following disadvantages.

That is, in the communication restart, for example, in the case of communication between a print data sending device and a printer, a node ID of a communication partner having a newer unique ID can be recognized.
Even if the transfer of print data is resumed, it is not due to a bus reset signal from another node. Because the machine has been reset, it is highly possible that the paper being printed will be ejected, and that the buffered print data is likely to be cleared. There is a disadvantage that normal printing is not performed with print data that is being received by transfer.

[0008]

SUMMARY OF THE INVENTION In order to solve the above problems and appropriately transmit and receive data between devices constituting a network, a communication system, a printing system, and a method thereof according to the present invention mainly include the following. It is characterized by comprising.

That is, in a communication system in which a plurality of devices are connected to a network, means for detecting connection reconfiguration of the devices constituting the network, and, based on the detection result, a cause of the connection reconfiguration of the network. Means for determining whether or not is a communication destination device during communication,
If the device at the communication destination causes the reconfiguration of the connection of the devices constituting the network, control is performed to forgo the continuation of the communication.

A printing system to which a device for transmitting and receiving print data via the IEEE 1394 is connected, a bus reset in the IEEE 1394 during the data transfer between the device for transmitting the print data and the device for processing the print data. , Detection means for detecting that the bus has been reconfigured, issuing means for interrupting the transfer of the print data based on the result of the detection, and determining whether or not to restart the transfer of the interrupted print data. Determination means for determining whether or not the bus reset is issued first from a device that is transmitting and receiving the print data, and is issued from a node of another device. If it is determined that the transfer of the print data has been completed, the transfer of the interrupted print data is restarted.

A communication method for transmitting and receiving data between a plurality of devices connected to a network includes a step of detecting a reconfiguration of a connection between devices constituting the network,
Judging whether or not the cause of the reconfiguration of the connection of the network is a device of a communication destination that is communicating, based on the result of the detection, wherein the device of the communication destination configures the network. If the reconfiguration of the connection is caused, control to stop continuation of communication is performed.

A print control method for controlling transmission and reception of print data between devices via IEEE 1394 is a method for controlling transmission and reception of print data between a device for sending print data and a device for processing the print data. A detection step of detecting that the bus has been reconfigured by issuing a bus reset; an interruption step of interrupting the transfer of the print data based on a result of the detection; and restarting the transfer of the interrupted print data. And determining whether or not the bus reset is issued first by the device that is transmitting and receiving the print data, and is issued from a node of another device. If it is determined that the transfer has been performed, the interrupted transfer of the print data is resumed.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) FIG. 1 is a diagram showing the configuration of a communication system according to the present invention. In FIG. 1, reference numeral 101 denotes an IEEE 1394 interface (I
/ F) Printer having 106, 102 is IEEE13
Personal computer with 94 I / F 107 (P
C), 103, 104 and 105 are IEEE13, respectively.
Connected device A having 94 I / Fs 108, 109, 110,
B, C, and 111, 112, 113, and 114 are IEEE 1394 cables for connecting the IEEE 1394 I / F of each device.

FIG. 2 is a detailed block diagram of the printer 101 in FIG. Referring to FIG. 1, reference numeral 201 denotes a printer engine that performs paper feeding and printing under the control of a printer controller 202, and 202 controls the printer engine 201 to cause the printer engine 201 to print print data from the IEEE 1394 I / F 203. It is a printer controller.

Reference numeral 203 denotes an IEEE 1394 protocol that performs IEEE 1394 protocol processing and transmits print data received via the IEEE 1394 to the printer controller 202.
Reference numeral 204 denotes a CPU for controlling the entire printer, and 205 denotes a ROM in which a program for operating the CPU 204 is stored.

Reference numeral 206 denotes a RAM used as a work or data buffer when the CPU 204 operates;
Is an I / F for transferring signals and data when controlling the printer engine 201, and 208 is a CPU 20.
Display means 209 for displaying the status of the printer by operating under the control of No. 4 is an input means for inputting a reset or paper discharge instruction to the printer 101.

Reference numeral 210 denotes the printer controller 202 and I
An I / F for exchanging signals and data with the IEEE 1394 I / F 203, and 211 is an IEEE 1
A CPU 394 controls the LINK chip 215 by the I / F 203 to perform IEEE 1394 protocol processing. A ROM 212 stores a program for operating the CPU 211, and 213 denotes a work or data buffer when the CPU 211 operates. R to use for
AM and 214 are connected to the printer controller 202 and IEEE.
This is an I / F for exchanging signals and data with the 1394 I / F 203.

215 is an IE under the control of the CPU 211.
LIN that performs EE1394 link layer protocol processing
K chip and 216 are LINK chip 215 and connector 2
A PHY chip 217 is connected to the PHY chip 217 and performs 1394 physical layer protocol processing.
An IEEE 1394 standard connector connected to
218 is an IEEE connecting the connector 217 to another node.
It is an E1394 cable.

FIG. 3 is a detailed block diagram of the PC 102 in FIG. In the figure, reference numeral 301 denotes a CPU that controls the entire PC 102; 302, a memory in which programs and data are stored and used when the CPU operates; and 303, a peripheral device controller for controlling peripheral devices of the PC. Reference numeral 304 denotes an external peripheral device which is external to the PC and operates under the control of the peripheral device controller 303. Reference numeral 305 denotes an internal peripheral device which is internal to the PC and operates under the control of the peripheral device controller 303. A peripheral device 306 is an IEEE device under the control of the CPU 301.
IEEE1394I that performs E1394 protocol processing
/ F, 307 is an IE under the control of the CPU 301.
LIN that performs EE1394 link layer protocol processing
A K chip 308 is a PHY chip 309 connected to the LINK chip 307 and the connectors 309 and 310 for performing protocol processing of the IEEE 1394 physical layer.
310 are I connected to the PHY chip 308, respectively.
EEE1394 standard connectors 311 and 312 are connectors for connecting connectors 309 and 310 to other nodes, respectively.
EEE1394 cable.

In such a configuration, the printer 10
1, PC 102, connected device A103, connected device B10
4. A communication network based on IEEE 1394 is constructed based on the question of the connection device C105. The details of the communication network protocol conform to the IEEE 1394 standard, and a detailed description is omitted here.

However, the node ID of each node is determined,
After the communication network is established, each node exchanges unique ID information unique to the communication device set in advance in each node, and each node in the printer, the PC, the connection device, and the like is connected to the communication network. The correspondence between the node ID and the unique ID is held. For example, in the PC 102, the node ID and the unique ID of each node are held in the memory 302 in correspondence with each other as shown in FIG. By maintaining this correspondence relationship, even after a bus reset occurs, even if the node ID changes, it is possible to use the unique ID to identify the communication partner that was communicating before the bus reset. Becomes

FIG. 4 shows a flow chart from the PC 102 to the printer 101.
9 is a flowchart of an operation when print data is sent out and printed out via the IEEE 1394 I / F. Hereinafter, the operation will be described with reference to FIG.

First, when a PC user gives a print request from the external peripheral device 304, the CPU 3 of the PC 102
01 recognizes the request via the peripheral device controller 303, prepares print data according to the content of the print request, and stores it in the memory 302 or an auxiliary storage device such as a hard disk of the external peripheral device 304 or the internal peripheral device 305. It is stored (S402).

Next, the CPU 301 of the PC 102
The data including the information for inquiring whether the printer 101 can receive the print data and print or not is stored in the IEEE 139.
4I / F 306 to the LINK chip 307,
The data is transmitted to the printer 101 via the PHY chip 308 that performs protocol processing of the IEEE 1394 I / F physical layer.

LINK chip 307, PHY chip 30
8 performs protocol processing of the LINK layer and the physical layer based on the IEEE 1394 I / F standard, respectively, and executes connectors 309 and 310 and IEEE 1394 cables 311 and 3 respectively.
12, the respective IEEE of the printer 101, the connection device A103, the connection device B104, and the connection device C105.
The communication protocol processing is performed with the E1394 I / Fs 106, 108, 109, and 110, and the PC 102 and the printer 1 are processed.
01 between the PC 102 and the printer 101.
Is used to inquire whether the printer can receive and print the data.
Send via 106.

In response to an inquiry from the PC 102 to the printer 101, the CPU 211 of the printer 101
By controlling the INK chip 215, the PHY chip 216,
The communication based on the IEEE 1394 protocol is performed via the connector 217, and the IEEE 139 of the PC 102 is communicated.
Data is exchanged with the 4 I / F 306 and the PC 10
When the printer receives the print data from printer 2 and inquires whether printing can be performed, it transmits the data to I / F 21
4 to the interface (I / F) 210 of the printer controller 202.

Data sent from the I / F 214 to the I / F 210 is analyzed by the CPU 204 of the printer controller. CPU 204 via I / F 207
Collect information such as the status of the printer engine 201,
The printer 101 determines whether printing is not possible, for example, a paper-out state, an ink-out state, a paper-jam state, and the like, and determines whether the printer 101 can perform printing through the IEEE 139 via the interface (I / F) 210.
4I / F203.

The printer controller 202 sends the IEEE
The data transmitted to the 1394 I / F 203 as to whether or not the printer 101 can perform printing is based on the IEEE 1394 I / F 203.
CPU 211 receives the result via the I / F 214 and sends the result to the LINK chip 215.
16, connector 217, IEEE1394 cable 21
8 and communicates with the PC 102 based on the IEEE 1394 protocol.

The data transmitted from the printer 101 to the PC 102 as to whether or not the printer 101 can perform printing is based on the PC
102, a LINK via a connector 309 and a PHY chip 308 in the IEEE 1394 I / F 306.
It is received by the chip 307 (step S403).

The data received by the LINK chip 307 as to whether or not the printer 101 can perform printing is stored in the CPU 3 of the PC.
01 and is determined (step S40).
4).

If printing is not possible with the printer 101 (No at step S404), printing is impossible for the user of the PC 102 under the control of the peripheral device controller using a display device or the like in the external peripheral device. The presence is displayed and notified (step S405).

If printing is possible (step S404-Ye)
In s), the print data is stored in the IEEE 1394 I / F 306.
(S406).

At this time, it is determined whether the transmission of the print data is completed in the PC 102 and the printing is completed (step S407). If the transmission of the print data has been completed and the printing has been completed, the printing process ends as it is (step S416).

In a state where the transmission of the print data is not completed (S407-No), if the printing is not completed,
The bus reset of the communication protocol of IEEE1394
PHY chip 30 in EEE1394 I / F306
8. It is determined whether or not detection has been performed via the LINK chip 307 (step S408). As a result, if a bus reset has not been detected (step S408-N
In o), the IEEE 1394I is sent to the printer 101 continuously.
The operation of sending print data via / F306 is continued (step S406).

If it is recognized via the IEEE 1394 I / F 306 that a bus reset has been detected, the
Bus reconfiguration processing is performed according to the E1394 communication protocol, and a node ID is acquired again (step S4).
09).

After that, each of the connected devices connected to the IEEE 1394 cable network, that is, the unique IDs of the printer 101, the connected device A 103, the connected device B 104, and the connected device C 105
Is read and acquired using a read transaction of the communication protocol of IEEE1394 (step S410). Unique ID acquired before bus reset and unique I acquired after bus reset
Compare D with each connected device and node ID after bus reset
(Step S411). For example, the relationship between the node ID and the unique ID before the bus reset is shown in FIG.
If the relationship between the node ID and the unique ID after the bus reset is as shown in FIG. 6 when the relationship shown in FIG. 6 is present, the unique ID of the printer 101 whose node ID was 1 before the bus reset is XXX00001. , The node ID becomes 3 after the bus reset. Thus, the node ID of the printer 101 after the bus reset is specified (step S412).

Whether the printer 101 first issues a bus reset to the printer 101 using the node ID specified by the printer 101, or whether the printer 101 repeats the bus reset, (Step S41), whether or not the bus reset signal received from one connector is repeated to another connector in order to be transmitted to the other connector.
3). In the printer 101, the state of the network is monitored via the PHY chip 216 and the LINK chip 215, and when the bus reset signal is repeated, it can be recognized through these chips.

When the printer 101 issues a bus reset signal via the LINK chip 215 and the PHY chip 216 under the control of the CPU 211, it can be naturally recognized that the printer itself has issued the bus reset signal.

When a reset is input to the printer 101 itself via the input means 209, the printer controller 202 recognizes the reset input, and
Printer controller 202, printer engine 20
1. The IEEE 1394 I / F 203 is reset.
The IEEE1394 I / F203 includes an I / F210 and an I / F210.
/ F214, a reset signal is transmitted to the CPU 2
Under the control of 11, the entire IEEE 1394 I / F 203 is reset. At this time, under the control of the CPU 211, the connection to the communication network is resumed.
Via the LINK chip 215 and the PHY chip 216,
Issues a bus reset signal to the communication network.

As described above, in the printer 101, the CPU 2
Since the bus reset is recognized and issued under the control of No. 11, the PC 102 can respond to the inquiry as to whether the printer 101 has issued the bus reset.

If the printer 101 has not reset the bus itself before receiving the bus reset, that is, if the printer 101 repeats the bus reset signal, the bus due to the reset of the printer 101 or the like is performed. Since it is not a reset, the print operation of the printer 101 is continuing, and the transmission of print data from the PC 102 to the printer 101 is continued as it is. (406)
If the printer 101 has issued a bus reset before receiving the bus reset, the printer 10
Since the possibility of a bus reset or the like due to the reset of the main body is very high, and the printout operation up to now is often interrupted, the transmission of the print data from the PC 102 to the printer 101 is not performed. Interrupt.
(414) Further, the user of the PC 102 is notified that the printout has been interrupted because the bus reset printing cannot be restarted. (415) (Second Embodiment) In the first embodiment, IEEE 1394 has been described as an example of a communication network. However, this may be another communication network having a similar bus reconstruction protocol.

(Third Embodiment) In the first embodiment, transfer of print data from a personal computer (PC) to a printer has been described as an example. However, this may be another data transfer. For example, in a case where one image data is transferred by a plurality of communication packets in a data transfer from a scanner to a PC, when a bus reset occurs during the transfer of the scanner data, a bus reset is issued from the scanner or the PC. Since the device that has issued the bus reset is likely to have reset the entire system, it is necessary to confirm whether the communication partner has issued the bus reset as in the first embodiment. When the bus reset has not been issued, the scanner data transfer is continued.

(Fourth Embodiment) In the first embodiment, one PC, one printer, and three connection devices are connected in a chain to form a communication network. It may be a configuration. For example, the number of connection nodes is not limited to five.
Regarding the connection configuration, for example, IEEE1394
, A tree-like connection configuration may be adopted.
As described above, there is no particular limitation as long as the configuration does not impair the features of the present invention.

[0044]

[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 supply a storage medium (or a recording medium) on which a program code of software for realizing the functions of the above-described embodiments is recorded to a system or an apparatus, and to provide a computer (or a computer) of the system or apparatus. It is needless to say that the present invention can also be achieved by a CPU or an MPU) reading and executing the program code stored in the storage medium. In this case, the program code itself read from the storage medium implements the functions of the above-described embodiment, and the storage medium storing the program code constitutes the present invention. Also,
When the computer executes the readout program code, not only the functions of the above-described embodiments are realized, but also the operating system (OS) running on the computer based on the instructions of the program code.
It goes without saying that a case where the functions of the above-described embodiments are implemented by performing some or all of the actual processing, and the processing performs the functions of the above-described embodiments.

Further, after the program code read from the storage medium is written into the memory provided in the function expansion card inserted into the computer or the function expansion unit connected to the computer, the program code is read based on the instruction of the program code. Needless to say, the CPU included in the function expansion card or the function expansion unit performs part or all of the actual processing, and the processing realizes the functions of the above-described embodiments.

When the present invention is applied to the storage medium, the storage medium stores program codes corresponding to the above-described flowchart (shown in FIG. 4).

[0048]

As described above, according to the present invention,
The following effects are obtained.

(1) It is possible to avoid a state in which communication with a communication partner that is unlikely to be normally performed in the subsequent communication is not normally performed in a state that causes reconfiguration of the communication system. effective.

(2) When the printer which is one of the communication devices is reset due to an error such as a paper jam while receiving the print data, and the printer is reconfigured, the communication system may be reconfigured. On the other hand, after the communication system is reconfigured, the reception of the print data is restarted in the middle of the print data, so that a situation in which a printer error is generated again can be avoided.

(3) Since the communicating party confirms that the communication partner can continue the communication after the reconfiguration of the communication system and then continues the communication, the traffic increase due to useless communication can be avoided. As a communication system, there is an effect that efficient communication can be performed.

[Brief description of the drawings]

FIG. 1 is a connection diagram illustrating a configuration example of a communication system according to the present invention.

FIG. 2 is a block diagram illustrating a configuration of a printer according to the first embodiment.

FIG. 3 is a block diagram illustrating a configuration of a PC according to the first embodiment.

FIG. 4 is a flowchart illustrating processing of a communication system according to the present invention.

FIG. 5 is a diagram illustrating an example of holding a node ID and a unique ID before a bus reset according to the first embodiment;

FIG. 6 is a diagram illustrating an example of holding a node ID and a unique ID after a bus reset according to the first embodiment.

[Explanation of symbols]

101 Printer 102 Personal Computer (PC) 103 Connected Device A 104 Connected Device B 105 Connected Device C 106, 107, 108, 109, 110 IEEE1
394 interface 110, 111, 112, 113 IEEE 1394 cable

Claims (10)

[Claims] 1. A communication system in which a plurality of devices are connected to a network, comprising: means for detecting connection reconfiguration of devices forming the network; and reconfiguration of connection of the network based on a result of the detection. Means for determining whether the cause of the communication destination is a device of the communication destination during communication, if the device of the communication destination is the cause of the reconfiguration of the connection of the devices constituting the network, A communication system which performs control to foresee communication continuation. 2. The communication system according to claim 1, wherein an interface conforming to the IEEE 1394 standard is applied to the connection of the devices constituting the network. 3. The communication system according to claim 1, wherein the device includes a printer. 4. The communication system according to claim 1, wherein the device includes a scanner. 5. A printing system to which a device for transmitting and receiving print data via IEEE 1394 is connected, wherein a data transmission between a device for transmitting print data and a device for processing the print data is performed in the IEEE 1394. Detecting means for detecting that the bus has been reconfigured by issuing a bus reset; interrupting means for interrupting the transfer of the print data based on a result of the detection; and restarting the transfer of the interrupted print data. Determination means for determining whether or not the issuance of the bus reset is not initially caused by the device transmitting and receiving the print data, but is issued from a node of another device. If it is determined that the transfer has been performed, the interrupted transfer of the print data is restarted. 6. The method according to claim 1, wherein before and after the bus reset, a node ID assigned to each device node based on a network configuration is compared with a unique ID of each device assigned regardless of the network configuration. The printing system according to claim 5, wherein the printing is performed. 7. The printing system according to claim 5, wherein the device that sends out the print data includes a personal computer. 8. The printing system according to claim 5, wherein the device that processes the print data includes a printer. 9. A communication method for transmitting and receiving data between a plurality of devices connected to a network, comprising: a step of detecting a reconfiguration of a connection of the devices constituting the network; Judging whether or not the cause of the reconfiguration of the network connection is the device of the communication destination during communication, wherein the device of the communication destination is the cause of the reconfiguration of the connection of the device constituting the network. A communication method characterized by performing control to stop the continuation of communication when the following condition is satisfied. 10. A print control method for controlling transmission / reception of print data performed between devices via IEEE 1394, the method comprising: transmitting data between a device transmitting print data and a device processing the print data; A detection step of detecting that the bus has been reconfigured by issuing a bus reset in IEEE1394; an interruption step of interrupting the transfer of the print data based on a result of the detection; A step of determining whether or not to resume, wherein the issuance of the bus reset was not initially caused by the device transmitting and receiving the print data, and the node of another device Wherein the transfer of the interrupted print data is resumed when it is determined that the print data has been issued from the printer.