JP2001257703A - Data communication unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve probability which allows restarting transfer of print data that is interrupted by bus reset. SOLUTION: In the case a bus reset detection section 214 detects bus reset during transfer of print data and the transfer of the print data is interrupted, a job processing section 215 holds execution of reconnect time-out processing until a log-in request is made for transfer of new print data even after the lapse of a reconnect period.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an IEEE (The Instit)
ute of Electrical and Electronics Engineers, Inc.) 1
SBP via serial interface according to 394
The present invention relates to a data communication device for performing data transfer between a partner device and a connected device connected to the own device according to a data transfer protocol conforming to -2 (Seral Bus Protocol 2).

[0002]

2. Description of the Related Art IEEE (The Institute of Electri) is a serial interface capable of high-speed data transfer.
cal and Electronics Engineers, Inc.) 1394 has been proposed. In addition, SBP-2 (Seral Bus Protocol 2) has been proposed as a protocol for realizing data transfer via a serial interface conforming to IEEE1394.

[0003] In IEEE1394, compared with SCSI (Small Computer System Interface) conventionally used as an interface between a computer and its peripheral devices, the ID of each connected device is automatically assigned and the connected device is kept turned on. It has various advantages, such as supporting removal (so-called hot swap).

[0004] In IEEE1394, the automatic assignment of the ID of each connected device (node) is realized as follows.

[0005] That is, each node is first a “Branch” that is connected to two or more nodes, or a “Leaf” that is connected to only one node. Recognize whether or not. Next, each node:
After a predetermined time elapses, a parent_notify signal is transmitted in order from nodes that have recognized themselves as “leaves”.
On the other hand, a node that recognizes itself as a "branch"
parent_notify parent_notify signal before sending
Send the child_notify signal to the node that sent the ify signal. In this way, the parent-child relationship between the nodes is determined. Then, the node recognizes itself as a "branch", and identifies a tree structure in which all nodes connected to itself have children as vertices (root) (tree identification).

Next, when the tree structure is identified, each node sends out a self-packet including the physical_ID and management information used by itself in a predetermined order, and transmits its own basic information to other nodes. Publish. Here, the number of transmissions of self-packet is entered in physical_ID. That is, the first node to send a self-packet is physical
The _ID is set to 0, and then the node that sends the self-packet sets the physical_ID to 1. By doing this,
The ID used by each node is automatically assigned (self-identification).

[0007] In IEEE1394, hot swap is performed when a new node is connected or a connected node is disconnected (for example, when the power is turned off) in a state where the bus connection topology is managed. Deletes information about the topology, performs tree identification and self-recognition again, and automatically assigns IDs of each node (bus reset).

By the way, in IEEE1394, data transfer between nodes is not performed during a bus reset.
For this reason, SBP-2 guarantees resumption of data transfer interrupted by a bus reset.

Conventionally, the restart of data transfer interrupted by a bus reset defined by IEEE1394 is guaranteed between nodes using SBP-2 as follows.

That is, if a bus reset occurs while data transfer from the node A to the node B is being performed and the data transfer is interrupted, the node B passes a reconnect period from the occurrence of the bus reset. If a data transfer other than the interrupted data transfer is requested during this period, the request is rejected and that effect is notified to the node that made the request. On the other hand, when there is a reconnect request from the node A, the interrupted data transfer is restarted. Therefore, by notifying the node B of the reconnect request within the reconnect period, the node A can restart the data transfer from the node A to the node B interrupted by the bus reset.

When no connection request is received from the node A within the connection period, the node B executes a connection timeout process, rejects the subsequent connection request from the node A, and stops the data transfer interrupted by the bus reset. And other data transfer requests can be accepted.

[0012]

In recent years, various power management techniques have been proposed as techniques for saving power of computers and peripheral devices. According to this type of technology, for example, when there is no input to the input device for a certain period of time, the computer is turned off and the computer shifts to a hibernate state. Can return to the original operating state.

However, if the above-described IEEE1394 and SBP-2 are used for data transfer between a computer and a peripheral device to which such a power management technique is applied in the same manner as in the related art, the following problems occur.

For example, if the power of the computer is turned off and the printer enters the hibernation state during printing of the printer,
A bus reset occurs when the power is turned off. As a result, the printer interrupts the reading of the print data from the computer and waits for a reconnection request from the computer. However, a hibernating computer does not return unless some input is provided. For this reason, when the printer is notified of the reconnection request after the return, the reconnection period may have already passed.

In this case, the printer determines that there is no reconnection request from the computer when the reconnection period has elapsed, executes a reconnect timeout process, performs a paper discharge operation, resets each unit, and ends the printing operation. Resulting in. For this reason, the transfer of the print data from the computer whose execution has been interrupted by the bus reset to the printer cannot be resumed.

The present invention has been made in view of the above circumstances, and an object of the present invention is to improve the probability that data transfer can be resumed when data transfer is interrupted by a bus reset. It is to provide a possible data communication device.

[0017]

In order to solve the above-mentioned problems, a data communication apparatus using IEEE1394 and SBP-2 according to the present invention has a configuration in which a new data transfer process is requested after a reconnect period has elapsed. Execution of the reconnect timeout process is suspended.

For example, when the data transfer being executed is interrupted by a bus reset, even after the elapse of the reconnect period, a data transfer process different from the data transfer interrupted by the bus reset is not required. As far as possible, a reconnect request from the partner device that has requested the data transfer process whose execution has been interrupted is accepted. Then, after the elapse of the reconnect period, before receiving the reconnect request, when a data transfer process different from the interrupted data transfer is requested, a reconnect timeout process is executed, and the connection connected to the own device is performed. Outputs a reset command to the device.

By doing so, the reconnect timeout process is not executed only when the reconnect period has elapsed. Therefore, for example, in the case where the above-described power management technique is applied, a bus reset occurs due to the transition of the partner apparatus to the sleep state, and the data transfer from the partner apparatus to the connected device of the own apparatus is interrupted. Even in this case, the probability that the data transfer can be restarted increases.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below.

FIG. 1 is a schematic configuration diagram of a system including a printer 2 to which an embodiment of the present invention is applied. Here, each of the computer 1, the printer 2, the scanner 3, and the digital video camera 4 is an IEEE (The Institute of
Electrical and Electronics Engineers, Inc.) It is assumed that a serial interface conforming to 1394 is provided and connected to each other via the interface. In this system, at least data communication between the computer 1 and the printer 2 is performed by SBP-2 (Seral B
It shall be performed according to a data transfer protocol conforming to the us protocol 2).

In the following, for the sake of simplicity, only the data transfer process between the computer 1 and the printer 2 will be described.

First, a print execution sequence performed between the computer 1 and the printer 2 will be described.

FIG. 2 is a diagram showing a print execution sequence performed between the computer 1 and the printer 2.

As shown, the print execution sequence is as follows.
1. 1. Login processing It is divided into print data transfer processing and 3. logout processing.

1. Login Process Computer 1 logs in to Printer 2 with Login ORB (Operation Request
Write Block Request 1 in which the storage area (specifically, the start address and the amount of transfer data) of the “st Block” is described.
Notify 001.

In response to this, the printer 2 executes the Write Respo
Reply nse. After that, the printer 2 reads the Read Block Address indicating the read start address and the predetermined read data amount.
The ests are sequentially generated for the number necessary to read all the data in the storage area described in the Write Block Request 1001. Here, generation of these multiple Read Block Requests is performed when one split transaction ends.
The data following the data read from the computer 1 by the transaction is generated and transmitted in order so as to be read in the next split transaction.
As a result, the printer 2 sends the Read B
Receive lock Response sequentially and get Login ORB.

Next, when the reading of the login ORB is completed, the printer 2 transmits a read start address and a Read Quadlet Request indicating a predetermined read data amount, reads the contents of the configuration ROM of the computer 1, and reads out the contents of the configuration ROM of the computer 1. By acquiring the GUID (global ID) of 1 etc., the computer 1 that has logged in is identified.

Then, the printer 2 writes a command block agent ORB in which a print data transfer instruction and a storage area of print data to be transferred are described.
Logi containing information such as the address of the side (ORB pointer)
n Send the Response as a Write Block Request, and then send a packet indicating that the Login ORB processing has ended as a Write Block Request.

2. Print data transfer processing Computer 1 sends the Login Res
Command Block Agen to ORB pointer indicated in ponse
t To write the ORB, send a Write Block Request 1002 describing the address where the ORB is stored.

In response to this, the printer 2 executes the Write Respo
Reply nse. Next, the printer 2 performs Write Block Requ
Command B stored at the address described in est 1002
Read Block Reques to read the lockAgent ORB
Generate and send t.

In response to this, the computer 1 executes Command
Read the packet containing the Block Agent ORB into the Read Block
Send as Response.

Next, the printer 2 executes the command stored in the Read Block Response notified from the computer 1.
In order to analyze the Block Agent ORB and obtain the print data of the storage area described in the ORB from the computer 1, a read start address and a predetermined data amount (for example, 2 Kbytes) that can be transferred in one split transaction are described. Read Block Requests are sequentially generated for the number required to read all the print data in the storage area described in the ORB. Here, the plurality of Read Block Requests are generated and transmitted in order such that, when one split transaction is completed, data following data read from the computer 1 by the transaction is read in the next split transaction. You. As a result, the printer 2 sends the Re
Receives the ad Block Response sequentially and obtains print data.

Thereafter, the printer 2 sets the Command Block Age
nt A packet indicating that ORB processing (print data transfer processing) has been completed is transmitted as a Write Block Request.

3. Logout Process The computer 1 notifies the printer 2 of a Write Block Request 1003 in which a storage area of the Logout ORB for the computer 1 to log out of the printer 2 is described.

In response to this, the printer 2 executes Write Resp
Reply onse. Thereafter, the printer 2 reads the read block address indicating the read start address and the predetermined read data amount.
quests are sequentially generated for the number required to read all the data in the storage area described in the Write Block Request 1003. Here, generation of these multiple Read Block Requests is performed when one split transaction ends.
The data following the data read from the computer 1 by the transaction is generated and transmitted in order so as to be read in the next split transaction.
As a result, the printer 2 sends the Read B
Receive lock Response sequentially and get Logout ORB.

Then, the printer 2 sends a packet indicating that the logout ORB processing has been completed to the Write Block Req.
Send as uest.

Next, a description will be given of a print data transfer resuming execution sequence performed between the computer 1 and the printer 2 when a bus reset occurs during the execution of the printing execution sequence and the sequence is interrupted.

When the above-described print execution sequence is executed and the print data is transferred between the computer 1 and the printer 2, for example, the scanner 3 is newly connected, or the computer 1 is shifted to the hibernation state and the power supply is switched off. When it is turned off, the sequence is interrupted and the bus is reset.

In the bus reset, as described above, each node erases information on the connection topology of the bus, and again performs tree identification and self-recognition to automatically assign node IDs. For this reason, before and after the bus reset, the node IDs of the computer 1 (or the computer 1 recovered from the hibernation state) and the printer 2 may change. Therefore, in the SBP-2, if the bus is reset while the computer 1 is logged in to the printer 2, the node ID of the computer 1 is reconfirmed with the printer 2 to which the computer 1 (or the computer 1 recovered from the hibernation state) is logged in. Reconnect processing is allowed.

FIG. 3 is a diagram showing a print data transfer restart execution sequence performed between the computer 1 and the printer 2.

This sequence is performed by a bus reset.
Each node erases information about the bus connection topology,
The process is executed after the tree ID and the self-recognition are performed again to automatically assign each node ID. This sequence includes: Recognition process of printer 2 by computer 1,
2. 2. Reconnect processing; Restart processing of print data transfer,
4. It is divided into logout processing.

1. Computer 1 Recognition Processing of Printer 2 The computer 1 acquires a GUID and other information necessary for node recognition from each node in order to recognize the correspondence between the node ID newly assigned by the bus reset and the node. That is, the computer 1 sends the Rea to each node.
d A Quadlet Request is sent, and the Read Qu
By executing the process of receiving adlet response, the contents of the configuration ROM are read from each node, and the GUI
Get information such as D. Thus, the printer 2 that has logged in before the bus reset is identified.

2. Reconnect Processing The computer 1 notifies the printer 2 of a Write Block Request 1004 in which the storage area of the Reconnect ORB for the computer 1 to reconnect to the printer 2 is described.

In response to this, the printer 2 executes Write Resp
Reply onse. After that, Printer 2 reads the Read Block
Requests are sequentially generated for the number required to read all data in the storage area described in the Write Block Request 1004. Here, generation of these multiple Read Block Requests is performed when one split transaction ends.
The data following the data read from the computer 1 by the transaction is generated and transmitted in order so as to be read in the next split transaction.
As a result, the printer 2 sends the Read B
Receive lock Response sequentially and get Reconnect ORB.

Next, when the reading of the Reconnect ORB is completed, the printer 2 transmits a Read Quadlet Request, reads the contents of the configuration ROM of the computer 1, and acquires the GUID of the computer 1, and the like. As a result, the printer 2 identifies the computer 1 that has logged in before the bus reset.

Then, the printer 2 executes the Reconnect ORB
Write a packet indicating that the processing of
Send as equest.

3. Resume processing of print data transfer In the print execution sequence interrupted by the bus reset, the computer 1
To write the Command Block Agent ORB for transfer of print data to the ORB pointer indicated in the gin Response packet, the address where the ORB was stored was described.
Send Write Block Request 1005.

In response to this, the printer 2 executes Write Resp
Reply onse. Next, printer 2 writes Write Block R
Comman stored at the address described in equest 1005
d To read the Block Agent ORB, use Read Block Re
Create and send a quest. Computer 1 receiving this
Sends the packet storing the Command Block Agent ORB as Read Block Response.

Next, the printer 2 executes the command stored in the Read Block Response notified from the computer 1.
Analyze the Block Agent ORB. Then, it is determined whether or not the print data storage area described in the ORB is the same as the print data storage area described in the Command Block Agent ORB whose execution has been suspended due to the bus reset.

In the same case, of the print data of the storage area described in the ORB, the OR
In the processing of B, only the print data that has not been
Generates Read Block Requests describing the read start address and the amount of data that can be transferred in one split transaction (for example, 2K bytes) in order to obtain all the unacquired data. I do. Here, generation of these multiple Read Block Requests is performed when one split transaction ends.
The data following the data read from the computer 1 by the transaction is generated and transmitted in order so as to be read in the next split transaction.
As a result, the printer 2 sends the Read B
Lock Responses are sequentially received, and unacquired print data is obtained by the processing of the Command Block Agent ORB whose execution has been interrupted by a bus reset.

On the other hand, if different, in order to obtain the print data of the storage area described in the ORB from the computer 1, the read start address and the predetermined data amount (for example, 2 Kbytes) that can be transferred in one split transaction are set. The described Read Block Requests are sequentially generated for the number required to read all the print data in the storage area. Here, generation of these multiple Read Block Requests is performed when one split transaction ends.
The data following the data read from the computer 1 by the transaction is generated and transmitted in order so as to be read in the next split transaction.
As a result, the printer 2 sends the Read B
Lock Responses are sequentially received, and print data of the storage area described in the ORB is obtained.

After that, the printer 2 sets the Command Block Ag
ent Sends a packet indicating that ORB processing (print data transfer processing) has been completed as a Write Block Request.

4. Logout Processing The computer 1 notifies the printer 2 of a Write Block Request 1006 in which a storage area of a Logout ORB for the computer 1 to log out of the printer 2 is described.

In response to this, the printer 2 executes Write Resp
Reply onse. After that, a Read Block Request for reading data from Computer 1 is sent to Write Block
The data is sequentially generated for the number necessary to read all the data in the storage area described in Request 1006. Here, this multiple
When one split transaction is completed, the Read Block Request is generated and transmitted in order so that the data following the data read from the computer 1 by the transaction is read by the next split transaction. This allows the printer
2 sequentially receives the Read Block Response from the computer 1 and obtains a Logout ORB.

Then, the printer 2 sends a packet indicating that the processing of the logout ORB has been completed to the Write Block Req.
Send as uest.

Next, the computer 1 and the printer 2 that realize the above-described sequence will be described.

First, the computer 1 will be described.

FIG. 4 is a schematic configuration diagram of the computer 1 shown in FIG.

As shown, the computer 1 has a data communication unit 11 and a computer main unit 12.

As shown in FIG. 5, the computer main unit 12 transfers data from a CPU 121, a memory 122, an external storage device 123 such as a hard disk device, and a portable storage medium 125 such as a CD-ROM or FD. A reading device 124 for reading; an input device 126 such as a keyboard and a mouse; a display device 127 such as a display;
Interface 128 for sending and receiving data between elements including 1
It has a configuration of a general electronic computer. It is assumed that the computer main unit 12 is running printer driver software for controlling the printer 2, and application software such as word processing software and graphic software for creating print data to be printed by the printer 2.

The computer 1 of the present embodiment has
When the power management technology as described in the problem to be solved by the invention is applied, and there is no input to the input device 126 for a certain period of time, the CPU 121 transmits the information of each unit of the computer main unit 12 and the data communication unit 11 ( Return information) and store it in the external storage device 123, etc., then turn off the power,
It shall transition to a hibernation state. Then, after any transition to the hibernate state, if any input is made to the input device 126, the power is turned on, and the CPU 121 reads the return information stored in the external storage device 123 or the like, and
By setting in each part of the data communication unit 11, it is assumed that the system returns from the sleep state to the operation state before the sleep.

The data communication unit 11 includes a PHY processing unit 111 that executes processing in the IEEE1394 physical layer, a Link processing unit 112 that executes processing in the IEEE1394 link layer,
A packet processing unit 113 for executing processing in the transaction layer of EEE1394, a bus reset detection unit 114 for detecting a bus reset defined in SBP-2, and a job processing unit for processing a data transfer protocol conforming to SBP-2
Has 115.

Here, each element constituting the data communication unit 11 is an ASIC (Application Specific Integrated Circuit).
s), may be configured in hardware by an integrated logic IC such as an FPLA (Field-Programmable Logic Array), or may be configured in software by a DSP (Digital Signal Processor). Further, the job processing unit 115 is provided with the CPU 12 of the computer main unit 11.
It may be realized by causing 1 to execute a predetermined program. In addition, the data communication unit 11 may be provided as one device attachable to the computer main unit 12.

The job processing unit 115 is provided with an ORB (Operation Request
est block), and requests the packet processing unit 113 to generate a packet necessary to transfer the est block to the printer 2. For example, Computer 1 logs in to Printer 2 /
A LoginORB / Logout ORB for logging out and a Command Block Agent ORB for the printer 2 to read out print data from the computer 1 are generated and stored in a predetermined storage area. Then, the printer 2 requests the packet processing unit 113 to generate a Write Block Request for the printer 2 to read these ORBs from the computer 1.

The job processing unit 115 transmits a command for the printer 2 to read out print data from the computer 1.
While the Block Agent ORB is running, the bus reset detector 114
When a bus reset is detected by the
Reconnect ORB for computer 1 to reconnect to printer 2 after completion of tree identification and self-recognition processing by
Is generated and stored in a predetermined storage area of the computer main body 11. Then, a Writ for the printer 2 to read the ORB from the computer 1 is sent to the packet processing unit 113.
Request generation of e Block Request and perform reconnect processing. After that, the packet processing unit 113 is again requested to generate a Write Block Request for the printer 2 to read from the computer 1 the Command Block Agent ORB whose execution has been interrupted.

Further, the job processing unit 115 has a command for the printer 2 to read the print data from the computer 1.
d If the computer 1 enters the hibernation state during the execution of the Block Agent ORB and then returns (in this case, the job processing unit 115 needs to return the computer 1 from the computer main unit 11 to the state before the halt. Reconnection information is received), and a reconnect process is performed in the same manner as described above. Then, the packet processing unit 113 writes the Command Block Agent ORB, whose execution has been interrupted by the bus reset due to the transition of the computer 1 to the hibernation state, from the computer 1 to the Write Block R.
Request generation of equest again.

The packet processing unit 113 includes a packet receiving unit 116
And a packet generation unit 117.

[0069] Packet receiving section 116 receives a packet from another node via PHY processing section 111 and Link processing section 112.

The packet generator 117 generates various packets conforming to IEEE1394. For example, the job processing unit 11
According to the instruction from 5, OR generated by the job processing unit 115
Write Block Reque for causing printer 2 to read B
st, or the Read received by the packet receiving unit 116.
The data requested by the Block Request is sent to the computer
Read from Block 12 and read block resp containing the data
or generate onse.

Next, the printer 2 will be described.

FIG. 6 is a schematic configuration diagram of the printer 2 shown in FIG.

As shown, the printer 2 has a data communication unit 21 and a printer main unit 22.

As shown in FIG. 7, the printer main body 22
A memory 222, a CPU 221 for controlling various units constituting the printer main body 21 by executing various programs stored in the memory 222, and a mechanism for printing data on a print medium (for example, ink A printhead, a platen, a carriage drive mechanism for driving a carriage on which the printhead is mounted, a paper feed mechanism, and a paper supply / discharge mechanism for supplying / discharging print media, etc.), and a data communication unit 22. I / F circuit that sends and receives data to and from
It has a general printer configuration such as 223.

The data communication unit 21 includes a PHY processing unit 211 that executes processing in the IEEE1394 physical layer, a Link processing unit 212 that executes processing in the IEEE1394 link layer,
A packet processing unit 213 that performs processing in the transaction layer of EEE1394, a bus reset detection unit 214 that detects a bus reset defined by IEEE1394,
And a job processing unit 215 that processes a data transfer protocol conforming to -2.

Here, each element constituting the data communication unit 21 is an ASIC (Application Specific Integrated Circuit).
s), may be configured in hardware by an integrated logic IC such as an FPLA (Field-Programmable Logic Array), or may be configured in software by a DSP (Digital Signal Processor). Further, the job processing unit 215 may be realized by causing the CPU 221 of the printer main unit 21 to execute a predetermined program. In addition, the data communication unit 21 may be provided as one device that can be attached to the printer main unit 22.

The packet processing unit 213 includes a packet receiving unit 216
And a packet generation unit 217.

The packet receiving section 216 has a print data buffer 2163, a general-purpose buffer 2162, and a reception selector 2161.

The print data buffer 2163 stores print data included in the Read Block Response notified from the computer 1 and transmits the stored print data to the printer main unit 22 in byte units, that is, as parallel data.

Here, the size of the print data buffer 2163 is determined by the Read Block Request (see the print execution sequence and the print data transfer restart execution sequence described above) generated by the printer 2 to obtain the print data from the computer 1. It is set to be larger (for example, 4 Kbytes) than a predetermined data amount (for example, 2 Kbytes) that can be transferred in one split transaction to be described.

The transmission timing of the print data stored in the print data buffer 2163 to the printer main body 22 may be, for example, the time when the data is stored in the print data buffer 2163.

The general-purpose buffer 2162 stores data included in a packet other than the Read Block Response storing print data.

The reception selector 2161 includes a PHY processing unit 211 and
The destination buffer of the packet received via the link processing unit 212 is selected. More specifically, if the received packet is a Read Block Response storing print data, the print data buffer 2163 is selected. If the received packet is a packet other than the Read Block Response storing print data, the general-purpose buffer 2162 is selected. SBP-2 (Seral Bus P
In rotocol 2), information indicating the type of the packet and the like is added to the packet. Receive packet selector 2162
Determines whether the received packet is a Read Block Response that stores print data by examining this information.

The packet generator 217 includes a print data generator 2173, a general-purpose generator 2172, and a transmission selector 2171.

The print data generation unit 2173 generates a Read Block Request for reading the print data from the computer 1, which describes the read start address and the read data amount. The print data generation unit 2172 monitors the free space of the print data buffer 2163 of the packet reception unit 216. Then, ReadBl is stored in the print data buffer 2163.
Confirm that there is free space for the read data amount described in the ock Request, and then generate the Read Block Request.

The general-purpose generating unit 2172 generates a packet other than the Read Block Request packet for reading the print data from the computer 1.

The transmission selector 2171 is a print data generation unit.
One of the 2173 and the general-purpose generation unit 2172 is selected, and the packet generated by the selected packet generation unit is transmitted to the computer 1 via the PHY processing unit 211 and the Link processing unit 212.

The job processing unit 215 includes an execution status monitoring unit 2151
And a job execution unit 2152.

The execution status monitoring unit 2152 includes a Command Block A for transferring the print data read from the computer 1.
For the gent ORB, the execution of the ORB is based on the number of Read Block Request packets generated by the print data generator 2172 according to the ORB and the number of Read Block Response packets received from the computer 1 in response to the Read Block Request. Count until complete.

The job execution unit 2152 analyzes the packet stored in the general-purpose buffer 2162 and performs a process according to the content.

For example, if the packet stored in the general-purpose buffer 2162 is a Login ORB / LogoutORB or a Reconnect OR
When the storage destination of B is a Write Block request in which the ORB is described, the general purpose packet generation unit 2172 is notified to obtain the ORB from the computer 1. In response to this, the general packet generation unit 2172 sends a Read Block Request to the Writ
Generate as many as necessary to read out ORBs whose storage area is described in e Block Request.

For example, the general packet buffer 21
The packet stored in 62 is the C for print data transfer.
Read Block Respo containing ommand Block Agent ORB
If nse, the print data generation unit 2173 is notified to obtain the print data of the storage area described in the ORB from the computer 1. In response to this, the print data generation unit 2173 generates Read Block Requests for the number required to read the print data in which the storage area is described in the ORB.

[0093] The generation of the above Read Block Request is performed when one split transaction ends.
The data subsequent to the data read from the computer 1 from the transaction is generated and transmitted in order so as to be read in the next split transaction.

When the bus reset is detected by the bus reset detection unit 214, the job execution unit 2152 initializes the packet generation unit 217 and the packet reception unit 216.

However, if the bus is reset during execution of the print data transfer processing shown in FIG. 2 (processing in accordance with the Command Block Agent ORB for transferring print data read from the computer 1), the printing of the packet receiving unit 216 is performed. The initialization of the data buffer 2163 waits until the reconnect period specified by SBP-2 has elapsed after the bus reset. Even after the reconnect period has elapsed, the computer 1 issues a Login ORB read instruction to execute a new print data transfer sequence (Wr shown in FIG. 2).
Do not perform until you receive ite Block Request 1001).

During the reconnect period or after the reconnect period elapses, before receiving a Login ORB read instruction for executing a new print data transfer sequence, the printing interrupted by the bus reset from the computer 1 is received from the computer 1. Reconnect to resume data transfer
ORB read instruction (Write Block Request 100 shown in Fig. 3)
When 4) is received, the process from the reconnect process to the logout process shown in FIG. 3 is performed.

At this time, in the print data transfer resuming process shown in FIG. 3, the execution of the print data storage area newly read from the computer 1 and indicated by the Command Block Agent ORB for transfer of the print data is interrupted by a bus reset. If it is the same as the print data storage area indicated by the Command Block Agent ORB, the print data buffer 2163 is not initialized. The job execution unit 2152 stores the print data storage area indicated by the ORB and the Read Block Request or Read Block Response when the execution of the ORB is interrupted by the bus reset, which is held in the execution status monitoring unit 2152.
From the number of packets of se, the storage area for print data that has not been acquired is specified, excluding the acquired print data (print data already read before the bus reset) for the ORB. Then, the unacquired print data is transferred to the computer 1
To the print data generation unit 2173 to obtain the print data.
In response to this, the print data generation unit 2173 reads the read block by the number necessary for reading the unacquired print data.
Generate request.

On the other hand, during the reconnect period or after the reconnect period, before receiving the Login ORB read instruction for executing a new print data transfer sequence, the computer 1 did not receive the Reconnect ORB read instruction from the computer 1. Or Reconnect
I received the ORB reading instruction, but the computer 1
Command for transferring newly read print data
The storage area of the print data indicated by the Block Agent ORB is the Command Block Age whose execution was interrupted by a bus reset.
If it is different from the print data storage area indicated by the nt ORB, or if a request to clear the buffer is received,
The print data buffer 2163 is initialized.

After the elapse of the reconnect period, Reconn
ect If a Login ORB read instruction for executing a new print data transfer sequence is received before receiving the ORB read instruction, the job execution unit 2152 initializes the print data buffer 2163 and executes the job processing unit. 215 initializes itself and sends an initialization command to the printer main unit 22 (reconnect timeout process). Upon receiving the initialization command, the printer main body 22 performs a paper discharging operation and initializes each part of the printer main body 22.

Next, the operation of the computer 1 and the printer 2 having the above configurations will be described.

First, the operation of the computer 1 will be described.

FIG. 8 is a flowchart for explaining the operation of the computer 1 in the print execution sequence shown in FIG.

First, upon receiving a print instruction from the computer main unit 12, the job processing unit 115 executes a login process shown in FIG. 2 (steps S801-S802).

More specifically, the job processing unit 115 provides a Login ORB for the computer 1 to log in to the printer 2.
Is generated and stored in a predetermined storage area. Then, the storage area of the Login ORB was described in the packet generator 117.
A Write Block Request (Login ORB read instruction 1001 shown in FIG. 2) is generated and transmitted to the printer 2. Then, it waits for the packet receiving unit 116 to receive a Write Response, which is a response to the Write Block Request, from the printer 2.

Write Response received from Printer 2
Indicates that log-in of the computer 1 is permitted (Yes in step S801), step S802
Then, the login processing is continued. On the other hand, if it is indicated that the login of the computer 1 is not permitted (No in step S801), the flow in FIG. 8 ends without executing the login process.

In step S 802, the packet generation unit 117 sends a request from the printer 2 via the packet reception unit 116.
Wait for ad Block Request. Then, the data read by the received Read Block Request is read, and a Read Block Response including the data is transmitted to the printer 2. This allows the Login ORB to be
Read in 2.

Then, the packet generation section 117 reads the Read Queries received from the printer 2 through the packet reception section 116.
The data read by the adlet Request is read, and a Read Quadlet Request including the data is transmitted to the printer 2. As a result, the content of the configuration ROM of the computer 1 is read by the printer 2, and the GUID (global ID) of the computer 1 is recognized. Next, the job processing unit 115 communicates with the printer via the packet receiving unit 116.
Command Block Agent ORB for print data transfer stored in Write Block Request received from 2
Obtain a Login Response that includes information such as the address (ORB pointer) of the printer 2 to which is to be written.

Next, the job processing section 115 executes the print data transfer process shown in FIG. 2 (step S803).

More specifically, the job processing unit 115 generates a Command Block Agent ORB for transferring print data, and stores it in a predetermined storage area. Then, the packet generation unit 117 writes a Write command for the printer 2 to read the ORB.
Block Request (Command Block Agent ORB shown in Fig. 2
A read instruction 1002) is generated and transmitted to the printer 2.
After that, the packet generation unit 117 reads out the data requested by the Read Block Request received by the packet reception unit 116, and transmits a Read Block Response including the data to the printer 2. This allows Command Block Agent O
Read RB into printer 2.

Then, the packet generation unit 117 reads out the data requested by the Read Block Request received by the packet reception unit 116, and reads the Read Block containing the data.
Send Response to Printer 2. This processing is performed by the packet receiving unit 116 with WriteBl indicating that the processing (print data transfer processing) according to the CommandBlock Agent ORB is completed.
Repeat until ock Response is received. This causes the printer 2 to read the print data.

Next, the job processing section 115 executes a logout process shown in FIG. 2 (step S804).

Specifically, the job processing unit 115 generates a Logout ORB for logging out of the printer 2,
It is stored in a predetermined storage area. Then, the packet generator 11
7 shows Write Bloc for printer 2 to read the ORB.
k Request (Logout ORB read instruction 1003 shown in Fig. 2)
Is generated and transmitted to the printer 2. After that, the packet generating unit 117 reads the Read Bloc received by the packet receiving unit 117.
The data requested by kRequest is read, and a Read Block Response including the data is transmitted to the printer 2. This causes the printer 2 to read the Logout ORB.

FIG. 9 is a flowchart for explaining the operation of the computer 1 in the print data transfer restart execution sequence shown in FIG.

When a bus reset occurs during the log-in to the printer 2 and the bus reset detecting unit 114 detects this (step S901), or during the log-in to the printer 2, the computer 1 shifts to a hibernate state and the power is turned off. After that, when the power is turned on to return from the hibernation state and the return information (including the information indicating that the user has logged in to the printer 2 is included) is received from the computer main unit 12 (step S902), the job processing unit 115 Initializes the packet processing unit 113 (step S903). Note that a bus reset (a bus reset occurs when the power of the computer 1 is turned on even when returning from the hibernation state), and the Link processing unit
Numeral 112 performs tree identification and self-recognition by emphasizing it with other nodes, and acquires node IDs.

Next, the job processing section 115 executes the printer 2 recognition process shown in FIG. 3 (step S904).

Specifically, the packet generation unit 117
Generate a uadlet Request and send it to the node with any node ID. Then, by receiving the Read Quadlet Response received as a response from the packet receiving unit 116, the content of the configuration ROM is read from the node and information such as the GUID is obtained. By performing this process for all the nodes, the correspondence between the node ID newly assigned by the bus reset and the node is recognized. Thus, the printer 2 that has logged in before the bus reset is identified.

Next, the job processing section 115 executes a reconnect process shown in FIG. 3 (steps S905-S906).

More specifically, a Reconnect ORB for reconnecting to the printer 2 is generated and stored in a predetermined storage area. Then, the packet generation unit 117 generates a Write Block Request (the Reconnect ORB read instruction 1004 shown in FIG. 3) for the printer 2 to read the ORB, and transmits the request to the printer 2. Then, the packet receiving unit 116
Write Response which is a response to te Block Request
Wait for printer 2 to receive.

Write Response received from Printer 2
Indicates that the reconnection of the computer 1 is permitted (Yes in step S905), step S90
Move to step 6 to continue the reconnect process. On the other hand, when it is indicated that the reconnection of the computer 1 is not permitted (No in step S905), the flow in FIG. 9 ends without executing the reconnect process.

At step S906, the packet generator 117 receives the Read Block Re
The data requested by the quest is read, and a Read Block Response including the data is transmitted to the printer 2. This causes the printer 2 to read the Reconnect ORB.

Next, the job processing section 115 executes the print data transfer restart processing shown in FIG. 3 (step S907).

More specifically, the command block in which a print data transfer instruction and a print data storage area to be transferred are described.
Generate ck Agent ORB and store it in the specified storage area.
Then, a write block request (Com shown in FIG. 3) for the printer 2 to read the ORB is sent to the packet generation unit 117.
mand Block Agent ORB read instruction 1005) is generated,
Send to printer 2. After that, the packet generation unit 117
The packet receiving unit 116 reads out the data requested by the Read Block Request, and reads the data containing the data.
d Send Block Response to Printer 2. This causes the printer 2 to read the Command Block Agent ORB.

Then, the packet generation unit 117 reads out the data requested by the Read Block Request received by the packet reception unit 116, and reads out the Read Block containing the data.
Send Response to Printer 2. This processing is performed by the packet receiving unit 116 by the WriteBloc indicating the end of the processing (print data transfer processing) according to the CommandBlock Agent ORB.
Repeat until k Response is received. This causes the printer 2 to read the print data.

When a bus reset (including a bus reset due to the transition of the computer 1 to the hibernation state) occurs during the print data transfer process shown in FIG.
nd Block Agent ORB
Write Block Request (Command Block Ag shown in Fig. 2)
If a bus reset occurs between the transmission of the ent ORB read instruction 1002) and the reception of a Write Block Response indicating the end of the processing according to the ORB, the job processing 115 A Write Block Request for causing the printer 2 to read the Command Block Agent ORB whose execution has been interrupted is generated again,
Send to printer 2.

Next, the job processing section 115 executes a logout process shown in FIG. 3 (step S908).

Specifically, a Logout ORB for logging out of the printer 2 is generated and stored in a predetermined storage area. Then, the printer 2 sends the packet generation unit 117
Generate a Write Block Request (Logout ORB read instruction 1006 shown in Fig. 3) for reading the ORB, and
Send to 2. Thereafter, the packet generation unit 117 reads out the data requested by the Read Block Request received by the packet
Send Response to Printer 2. This allows for a Logout
The ORB is read by the printer 2.

Next, the operation of the printer 2 will be described.

FIG. 10 is a flowchart for explaining the operation of the printer 2 in the print execution sequence shown in FIG.

First, the job execution unit 2152 executes the login processing shown in FIG. 2 (steps S1001-S1002).

More specifically, the job execution unit 2152 receives a Write Block Request (Login ORB read instruction 1001 shown in FIG. 2) describing the storage area of the Login ORB from the computer 1 via the general-purpose buffer 2162. Then, it is determined whether or not the login of the computer 1 is permitted.

If the login of the computer 1 is permitted (Yes in step S1001), the general-purpose generation unit 2172
Write Re indicating that login to computer 1 is permitted
A sponse is generated and transmitted to the printer 2, and then the process proceeds to step 1002 to continue the login process. on the other hand,
If login of computer 1 is not allowed (for example, S
During the reconnect period specified in BP-2) (Step S1
(No in 001), generates a Write Response indicating that computer 1 login is not permitted, and
2 and thereafter terminates the flow of FIG. 10 without executing the login process.

In step S1002, the job execution unit 2152 sends the ReadBlock Request to the general-purpose generation unit 2172,
Login O with storage area described in Write Block Request
Generate as many RBs as necessary to read
Send to And the response, Read Block Resp
onse is received via the general purpose buffer 2162. As a result, the Login ORB is read from the computer 1.

Next, the job execution unit 2152 executes the login ORB
When the reading of the data has been completed, the general-purpose
Generates a Let Request and sends it to the computer 1, and sends the Read Quadlet Response as a response to the general-purpose buffer 2.
Receive via 162. Thereby, the contents of the configuration ROM of the computer 1 are read, the GUID of the computer 1 and the like are acquired, and the computer 1 that has logged in is identified.

The job execution unit 2152 includes information such as the address (ORB pointer) of the printer 2 to which the Command Block Agent ORB in which the print data transfer instruction and the print data storage area to be transferred are described is written. Generate Login Response and include Write Blo
The general-purpose generating unit 2172 generates an ck Request and transmits it to the computer 1. After that, the versatility generation unit 2172
Writ containing data indicating that ORB processing has been completed
Generate e Block Request and send it to Computer 1.

Next, the job execution unit 2152 executes the print data transfer process shown in FIG. 2 (step S1003).

More specifically, the job execution unit 2152 receives, from the computer 1 via the general-purpose buffer 2162, a command data transfer instruction and a storage area of the Command Block Agent ORB in which the storage area of the print data to be transferred is described. W indicated
rite Block Request (Command Agent ORB shown in Fig. 2
Upon receiving the read instruction 1002), the general-purpose generation unit 2172
Generate an ite Response and send it to the computer 1.
Then, the job execution unit 2152 causes the general-purpose generation unit 2172 to generate a Read Block Request for reading the Command Block Agent ORB from the storage area described in the Write Block Request from the computer 1 and transmit the Read Block Request to the computer 1, and in response to the response, A certain Read Block Response is received from the general-purpose buffer 2162. This allows the computer 1
Read Command Block Agent ORB from

Next, the job execution unit 2152
In order to obtain from the computer 1 the print data of the storage area indicated by the Command Block Agent ORB read from
The print data generation unit 2173 generates a Read Block Request. Then, a Read Block Response is received from the computer 1 as a response to the ReadBlock Request, and is stored in the print data buffer 2163, thereby receiving the print data in the storage area indicated by the ORB.

The job execution unit 2152 executes the command
When the read processing of the print data in the storage area indicated by the nt ORB is completed, the command block A is
Write Block Req indicating that gentORB processing has been completed
Generate uest and send it to computer 1.

Next, the job execution unit 2152 executes the logout process shown in FIG. 2 (step S1004).

More specifically, the job execution unit 512 sends a Write B indicating the storage area of the Logout ORB from the computer 1.
lock Request (Logout ORB read instruction 100 shown in Fig. 2)
3) is received via the general-purpose buffer 2162. And W
Logout O from the storage area indicated in the rite Block Request
To read the RB, the general-purpose generation unit 2172 sends the Read Block R
An equest is generated and transmitted to the computer 1, and a response, Read BlockResponse, is received via the general-purpose buffer 2162. Thus, the Logout ORB is read from the computer 1.

Upon completion of the reading process of the Logout ORB, the job execution unit 2152 sends the Logout ORB to the general-purpose generation unit 2172.
Write Block Request indicating that processing of B has been completed
Is generated and transmitted.

FIG. 11 is a flowchart for explaining the operation of the printer 2 in the print data transfer restart execution sequence shown in FIG.

When a bus reset occurs during the log-in of the computer 1, the execution status monitoring unit 2151 detects this via the bus reset detection unit 214 (step S1101), and connects each unit of the packet generation unit 217 to the print data. Buffer 2163
Each unit of the packet receiving unit 216 except for is initialized (step S1102).

It should be noted that the link processing unit 21
2 performs tree identification and self-recognition in cooperation with other nodes to acquire node IDs. The printer 2 shown in FIG.
Read Quadlet Reque from Computer 1
When st is transmitted, the packet processing unit 213 receives this in the general-purpose buffer 2162 and reads out the data requested by the Request. Then, the general-purpose generation unit 2172 generates a Read Quadlet Response including the data, and transmits the response to the computer 1. As a result, information such as the GUID described in the configuration ROM of the printer 2 is
Notify computer 1.

Next, after the bus reset is detected, the job execution unit 2152 executes the reconnection period defined by SBP-2 (step S2).
1104) or after the reconnection period has elapsed and before receiving a login request for new print data transfer (step S1105), it is determined whether or not a reconnection request has been made (step S1103).

More specifically, the job execution unit 2152 examines the packet stored in the general-purpose buffer 2162, and executes a new print data transfer within the reconnect period specified by SBP-2 or after the reconnect period elapses. Before receiving the login request (Login ORB read instruction 1001 shown in FIG. 2),
Write Block Request indicating the storage area of Reconnect ORB from computer 1 (Reconnect ORB shown in Fig. 3
The determination is made based on whether or not the read instruction 1004) has been received.

If no reconnection request is made within the reconnection period or after the reconnection period has elapsed and before a login request for new print data transfer is received, initialization of the print data buffer 2163 and job processing The unit 215 initializes itself and sends an initialization command to the printer main unit 22 (reconnect timeout process) (steps S1113 and S1114). Then, the flow shown in FIG. 10 is executed (step S1115).

In the reconnect period, a login request for new print data transfer (Login ORB shown in FIG. 2)
Upon receiving the read instruction 1001), the job execution unit 2152
Causes the general-purpose generation unit 2172 to generate a Write Response indicating that login of the computer 1 is not permitted, and transmits the Write Response to the printer 2.

On the other hand, if a reconnection request is received from the computer 1 within the reconnect period or after the reconnect period and before receiving a login request for new print data transfer, the job execution unit 2152 returns to FIG. By executing the reconnect process shown, it is recognized that the node requesting the reconnect is the computer 1 (step S1106).

More specifically, the job execution unit 512 sends the Wri in which the storage area of the Reconnect ORB is indicated by the computer 1.
Upon receiving the te Block Request (Reconnect ORB reading instruction 1004 shown in FIG. 3), the general-purpose generation unit 2172 writes the Write Re
Generate sponse and send it to computer 1. Then, the job execution unit 2152 writes the WriteBlo
Reconnect ORB from the storage area described in ck Request
Block Reque for reading data from computer 1
st is generated and transmitted to the computer 1, and the response, Read Block Response, is received from the general-purpose buffer 2162. As a result, the Reconnect ORB
Is read.

Next, the job execution unit 2152
When the reading of the RB is completed, the general-purpose
Generate uadlet Request and send it to Computer 1,
The response, Read Quadlet Response, is received from the general-purpose buffer 2162. Thereby, the content of the configuration ROM of the computer 1 is read, and the GUID of the computer 1 and the like are obtained. As a result, the job execution unit 2152 identifies that the node that has requested the reconnection is the computer 1 that has logged in before the bus reset.

Thereafter, the job execution unit 2152
2172 causes the computer 1 to generate a Write Block Request including data indicating that the processing of the Reconnect ORB has been completed, and sends it to the computer 1.

Next, the job execution section 2152 executes the print data transfer restart processing shown in FIG. 3 (steps S1107 to S11).
11).

More specifically, the job execution unit 2152 receives, via the general-purpose buffer 2162, the storage area of the Command Block Agent ORB in which the transfer instruction of the print data and the storage area of the print data to be transferred are described from the computer 1. W indicated
rite Block Request (Command Block Agen shown in Fig. 3
t When the ORB read instruction 1005) is received, the general-purpose generation unit 2172
Then, a Write Response is generated and transmitted to the computer 1. Then, the job execution unit 2152
Then, the computer 1 generates a ReadBlock Request for reading the Command Block Agent ORB from the storage area described in the Write Block Request, transmits the ReadBlock Request to the computer 1, and receives a Read Block Response as a response from the general-purpose buffer 2162. As a result, the Command Block Agent ORB for transferring the print data is read from the computer 1 (step S1107).

Next, the job execution unit 2152 sends a command block agent for transferring print data to the execution status monitoring unit 2151.
If the ORB is retained, retrieve the ORB and
A comparison is made with the Command Block Agent ORB acquired in S907 (step S1108).

As described above, the execution status monitoring unit 2151
For transferring print data read from computer 1
For the Command Block Agent ORB, the Read Block Requeue generated by the print data generator 2172 according to the ORB
The number of packets of st and the Read Block received from Computer 1 in response to the Read Block Request
The number of Response packets is counted until the execution of the ORB is completed. Therefore, the OR
If the execution of B is interrupted, the execution status monitoring unit 2151
For the ORB, the read data generated by the print data generation unit 2172 according to the ORB until the bus reset is performed.
The number of ck Request packets and the corresponding Read Block Request
Rea received from computer 1 in response to
The number of d Block Response packets will be retained.

As a result of the comparison in step S1108, the Command Block Agent ORB stored in the execution status monitoring unit 2151
If the storage area of the print data indicated by (1) and the storage area of the print data indicated by the Command Block Agent ORB acquired in step S907 are the same, the job execution unit 2152 performs the following to ensure the continuity of the print data before and after the bus reset. Is performed.

That is, the job execution unit 2152
The storage area of the print data indicated by the Command Block Agent ORB acquired in S1107 (actually specified by the start address and the amount of transfer data) and the number of packets of Read Block Request held by the execution status monitoring unit 2151 or the Read From the number of packets in the Block Response, the print data storage area for the unacquired print data is specified for the ORB excluding the acquired print data (the print data already read before the bus reset).

Then, the job execution unit 2152 instructs the print data generation unit 2173 to acquire only the unacquired print data from the computer 1 by the number of read blocks required to read the unacquired print data. generate a request,
Send to computer 1. Then, the Read Block R
ReadBlo from computer 1 in response to equest
ck Response is received and this is the print data buffer.
By storing it in 2163, only the unacquired print data is received (step S1109).

When the execution of the Command Block AgentORB for transferring print data is completed, the execution status monitoring unit 2151 clears the measurement contents. Then, when a new Command Block Agent ORB for transferring print data is executed, measurement is started.

On the other hand, if the execution status monitoring unit 2151 does not hold a Command Block Agent ORB for transferring print data, or if the result of the comparison in step S1108 is
Command Block A held in the execution status monitoring unit 2151
Storage area for print data indicated by gent ORB and step S1107
If the storage area of the print data indicated by the Command Block Agent ORB acquired in step S1107 is different, the job execution unit 2152 obtains the print data of the storage area indicated by the Command Block Agent ORB acquired in step S1107 from the computer 1, The application generation unit 2173 generates a Read Block Request and sends it to the printer 2. And the Read B
R from computer 1 in response to lock Request
By receiving the ead Block Response and storing it in the print data buffer 2163, the print data in the storage area indicated by the ORB is received (step S1110).

Next, the job execution unit 2152 determines in step S110
9 or when the print data reading process in step S1110 is completed, the general-purpose generation unit 2172 generates a Write Block Request indicating that the processing of the Command Block Agent ORB acquired in step S1107 is completed, and transmits it to the computer 1 (step S1111).

Next, the job execution unit 2152 executes the logout process shown in FIG. 3 (step S1112).

More specifically, the job execution unit 2152 sends the Write B indicating the storage area of the Logout ORB from the computer 1.
lock Request (Logout ORB read instruction 100 shown in Fig. 3)
6) is received via the general-purpose buffer 2162. And
Logout from the storage area indicated in the Write Block Request
To read the ORB, the general-purpose generation unit 2172 sends a Read Block
A request is generated and transmitted to the computer 1, and a response, Read Block Response, is received via the general-purpose buffer 2162. Thus, the Logout ORB is read from the computer 1.

Upon completion of the reading process of the Logout ORB, the job execution unit 2512 sends the logout ORB to the general-purpose generation unit 2172.
Write B containing data indicating that processing of B has been completed
Generate lockRequest and send it to Computer1.

As described above, one embodiment of the present invention has been described.

As described above, conventionally, in order to resume the transfer of the print data interrupted by the bus reset, the computer sends a reconnect request (specifically, the storage area of the Reconnect ORB) to the printer within the reconnect period. (Notification of Write Block Request in which is described). If there is no reconnect request within the reconnect period, the printer performs a reconnect timeout process to perform a paper ejection operation and initialization of each part of the printer,
The printing operation has been completed.

However, when the power management technique for power saving is applied to the computer 1 as in the present embodiment, while the computer 1 is logging in to the printer 2 for transferring the print data, Since there has been no input to the input device 126 of the computer 1 for a predetermined period, the power of the computer 1 is turned off and the computer 1 shifts to a hibernation state, so that a bus reset may occur. In this case, the printer 2 waits for a request for reconnection from the computer 1, but the computer 1 is in a suspended state.
Does not return unless some input is made to the input device 126. Therefore, when the printer 2 is notified of the reconnection request after the return, there is a possibility that the reconnection period has already passed.

In this regard, the printer 2 of the present embodiment suspends execution of the reconnect timeout process until a login request for a new print data transfer is issued even after the reconnect period has elapsed. . Therefore, if the bus reset occurs due to the transition of the computer 1 to the hibernation state and the transfer of the print data from the computer 1 to the printer 2 is interrupted, the transfer of the new print data to the printer 2 is performed even after the reconnect period has elapsed. Before the log-in request is made, the computer 1 can be connected to the printer 2 after returning from the hibernation state.

As described above, according to the present embodiment, the probability that the transfer of the print data interrupted by the bus reset can be restarted is increased.

When the transfer of the print data by the Command Block Agent ORB is interrupted by a bus reset, the printer 2 of the present embodiment transmits only the unacquired print data by the ORB before the bus reset to the computer. I'm trying to get from one.

More specifically, a request for a reconnect process defined in SBP-2 is received from the computer 1 which has notified the Command Block Agent ORB whose execution has been interrupted due to the bus reset, and
If the same Command Block Agent ORB as the Agent ORB is received, the job execution unit 2152 reads the execution status of the ORB measured by the execution status monitoring unit 2151 when the execution of the ORB is interrupted.
Block Request transmission count or Read Block Respo
Based on the number of receptions of nse, the storage area of the unacquired data excluding the data acquired before the bus reset is specified from the data of the storage area described in the ORB. And
A ReadBlock Request is sent to the print data generation unit 2173.
Are generated for the number required to read the specified unacquired data, and transmitted to the computer 1.

Further, the reception selector 2161 is connected to the Read Bl
In response to the ock Request, Computer 1 sends a Re
The print data stored in the ad Block Response is stored in the print data buffer 2163. Job execution unit 2152
Even if the bus is reset, instead of immediately resetting the print data buffer 2163, if the computer 1 does not reconnect within the reconnect period defined in SBP-2 after the completion of the bus reset, I try to initialize.

By doing so, the printer 2 can continue the print data stored in the print data buffer 2163 without duplicating the same print data even when the reception is interrupted by a bus reset. Nature can be secured. Therefore, for example, in a serial printer such as an ink jet printer, 1
When the print data for the line (the print head can be scanned once) is received, the same print data will not be duplicated after the bus reset even if the printing is started.

A Read Block for storing print data
Packets other than Response (for example, Logout ORB or C
Write Bl showing storage area of ommand Block Agent ORB
ockRequest) is stored in the general-purpose buffer 2162 via the reception selector 2161. Here, the job execution unit 2152
When the bus is reset, the general-purpose buffer 2162 is immediately initialized. Therefore, for example, when the bus is reset during the reception of the Write Block Request indicating the storage area of the Logout ORB or the Command Block Agent ORB, the fragment of the Write Block Request interrupted by the bus reset is transferred to the general-purpose buffer 2.
By remaining in the 162, occurrence of a situation in which the printer 2 performs an erroneous operation after the bus reset can be reduced.

Further, in the present embodiment, the size of the print data buffer 2163 is determined by the Read Block Resize generated by the printer 2 to obtain the print data from the computer 1.
The value is set to a value (for example, 4 Kbytes) larger than a predetermined data amount (for example, 2 Kbytes) that can be transferred in one split transaction described in quest. Therefore, the print data of the Read Block Response transmitted by the computer 1 as a response to the Read Block Request is stored in the print data buffer 2163 at a time. Therefore, the execution status monitoring unit 2151 uses Command Bloc
k The execution status of the job (print data transfer / transfer resumption processing) by the Agent ORB can be realized by measuring the number of times Read Block Request is sent or the number of times Read Block Response is received, and management becomes easy.

In this embodiment, Command Block A
Command Bloc to monitor the execution status of the gent ORB
k Number of transmissions of Read Block Request for reading print data in the storage area described in Agent ORB, and
Although both the number of receptions of the Read Block Response, which is the response to the Request, are measured, one of them may be measured. Alternatively, the Read Block Resp
The execution status of the Command Block Agent ORB may be monitored by measuring the total number of bytes of print data included in onse. This can be realized, for example, by measuring the number of bytes of data input to the print data buffer 2163.

Further, in the present embodiment, description has been made of a device which performs data communication with a partner device according to a data transfer protocol conforming to SBP-2 via a serial interface conforming to IEEE1394, but the present invention is not limited to this. It is not something to be done. For example, DPP (Direct Printer
Other data transfer protocols such as Protocol) can be widely applied to those in which data transfer may be interrupted by a predetermined event.

Further, the data communication apparatus of the present invention is not limited to being applied only to a printer, but is applicable to various connected devices such as a scanner and a digital video camera.

[0180]

As described above, according to the present invention,
The probability that the data transfer interrupted by the bus reset can be restarted is increased.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a system including a printer 2 to which an embodiment of the present invention is applied.

FIG. 2 is a diagram showing a print execution sequence performed between a computer 1 and a printer 2 shown in FIG.

FIG. 3 is a diagram showing a print data transfer restart execution sequence performed between the computer 1 and the printer 2 shown in FIG. 1;

FIG. 4 is a schematic configuration diagram of a computer 1 shown in FIG.

FIG. 5 is a diagram showing an example of a hardware configuration of a computer main unit 12 shown in FIG.

FIG. 6 is a schematic configuration diagram of the printer 2 shown in FIG.

FIG. 7 is a diagram showing an example of a hardware configuration of a printer main body 22 shown in FIG.

8 is a flowchart for explaining the operation of the computer 1 in the print execution sequence shown in FIG.

FIG. 9 is a flowchart for explaining the operation of the computer 1 in the print data transfer restart execution sequence shown in FIG. 3;

FIG. 10 shows a printer in the print execution sequence shown in FIG. 2;
FIG. 6 is a flowchart for explaining the operation 2;

11 is a flowchart for explaining the operation of the printer 2 in the print data transfer restart execution sequence shown in FIG.

[Explanation of symbols]

 1 Computer 2 Printer 3 Scanner 4 Digital video camera 11, 21 Data communication unit 12 Computer main unit 22 Printer main unit 111, 211 PHY processing unit 112, 212 Link processing unit 113, 213 Packet processing unit 114, 214 Bus reset Detecting units 115, 215 Job processing units 116, 216 Packet receiving units 117, 217 Packet generating units 121, 221 CPU 122, 222 Memory 123 External storage device 124 Reading device 125 Storage medium 126 Input device 127 Display device 128 Interface 223 I / F circuit 224 ... Printer engine 2161 ... Receive selector 2162 ... General purpose buffer 2163 ... Print data buffer 2171 ... Transmit selector 2172 ... General purpose generation unit 2173 ... Print data generation unit 2151 ... Execution status monitoring unit 2152 ... Job execution unit

Claims (5)

[Claims] [Claim 1] IEEE (The Institute of Electrical and
Electronics Engineers, Inc.) SBP-2 (Seral Bus Proto) via serial interface compliant with 1394
According to the data transfer protocol according to col 2),
A data communication device that performs data transfer between a partner device and a connected device connected to its own device. If a data transfer being executed is interrupted by a bus reset defined by IEEE1394, the SBP-2 Even after the elapse of the reconnect period specified in, a request for a data transfer process whose execution has been interrupted has been requested unless a data transfer process different from the data transfer interrupted by the bus reset is required. A data communication device characterized by recognizing a reconnect request specified by SBP-2 from a partner device. 2. The data communication device according to claim 1, wherein, when the data transfer being executed is interrupted by the bus reset, after the reconnect period elapses, the data transfer is interrupted. Before receiving a reconnect request from a partner device that has requested the data transfer, when a data transfer process different from the interrupted data transfer is requested, outputting a reset command to the connected device. apparatus. 3. The data communication device according to claim 1, further comprising a buffer for temporarily storing data to be transferred to said connected device, received from a partner device, and said data being executed by said bus reset. In the case where the transfer is interrupted, after the elapse of the reconnect period, before receiving a reconnect request from the partner device that has requested the processing of the data transfer whose execution has been interrupted, a data transfer different from the data transfer whose execution has been interrupted. A data communication device that clears the data stored in the buffer when the processing of (1) is requested. 4. The data communication device according to claim 1, wherein when the data transfer being executed is interrupted by the bus reset, before the elapse of the reconnect period or the reconnect period. If a reconnect request is received from the partner device that has requested the processing of the data transfer whose execution has been interrupted before the data transfer processing different from the data transfer whose execution has been interrupted has been requested after the elapse of A data communication device for requesting a partner device to transfer only unacquired data among data to be transferred in data transfer whose execution has been interrupted. 5. The data communication device according to claim 1, wherein the connection device is a printer, and the data to be transferred in the data transfer is print data. Communication device.