JPH10289070A - Network printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently notify printer status to many unspecified host computers in a printer that has a network interface which is directly connected to a network. SOLUTION: When each host computer 3 sends a command that requests for status reply to a printer 1, an interface controlling part 7 first reserves a memory area for flags and next makes the flags 15 on. The part 7 periodically checks the states of all the flags 15A to 15C that stand and sends a status reply character string that shows printer status 17 to host computers which correspond to the flags in an on state. The part 7 compares a status reply character string that is currently sent with the status reply character string that is sent the last time and omits the current transmission when both are the same.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printer which can be directly connected to a computer network, and more particularly to an improved status reply function for notifying the status of a printer to an unspecified number of computers.

[0002]

2. Description of the Related Art Many printers have a status of notifying a host computer of the status of the printer (for example, status such as standby / busy / error, details of error, remaining ink amount, presence / absence of paper, selection of paper path, etc.). Has a reply function. The printer status is generally sent to the host computer in the form of a character string, and this character string is called a status reply character string or the like.

[0003] Printers having a plurality of host interfaces so that a plurality of host computers can be connected are known. This type of printer has a host interface automatic switching function of recognizing which host interface data has arrived and setting only the host interface to a selected state during reception of the data. The status reply function of the conventional printer having the interface automatic switching function is to send a status reply character string to only one selected host interface.

[0004] Further, a conventional printer periodically notifies a host computer of a status reply character string at a predetermined time interval.

[0005] The host interface is for connecting the printer directly to the host, and the number of connectable hosts is naturally limited by the number of host interfaces. On the other hand, the network interface can be connected to an unspecified number of host computers by having one, and can be indirectly connected to an unspecified number of host computers via a network.

[0006]

In a conventional printer having a host interface automatic switching function, a host interface in a non-selected state is not notified of the printer status. When trying to send data to
It is only possible to obtain a recognition that a communication error has occurred. Therefore, on the host computer in the non-selected state, the transmitted data cannot be accepted by the printer, for example, because another host computer is in use, an error has occurred, or there is a problem with the communication path. It is not possible to judge, and it is not possible to judge whether communication is possible after a short wait, or whether it is necessary to solve the problem.

In a conventional printer, a printer status is periodically notified. However, if there is no change in the printer status, such a periodic notification is a useless communication, and the useless communication causes a delay in the essential printing process.

Further, the conventional printer is based on the premise that the printer has a plurality of host interfaces, and intends to reply the status to the host interface. There was a problem that the status could not be returned to the computer.

Accordingly, an object of the present invention is to provide a network printer having a network interface.
An object of the present invention is to allow any unspecified number of host computers to be notified of a printer status.

Another object of the present invention is to eliminate unnecessary transmission of a printer status character string between a host computer and a printer.

[0011]

A network printer according to a first aspect of the present invention comprises a network interface for connecting to a plurality of network computers, and a requesting computer identification means for identifying a computer requesting a status reply. A status reply unit for transmitting status information indicating a printer status to each of the computers identified by the identification unit.

According to this network printer, status information is sent to the host computer requesting a status reply.

In a preferred embodiment, in response to data requesting a status reply received from a plurality of host computers on a network, a flag corresponding to the host computer is provided as needed, and the state of the flag is turned on. Means for checking the status of all flags;
Means for transmitting status information to each of the host computers corresponding to the flags in the ON state.

According to this embodiment, if each host computer once sends data requesting a status reply to the printer, the corresponding flag is turned on.
Thereafter, the printer can be notified of the printer status.

A network printer according to a second aspect of the present invention comprises a network interface for connecting to a network, detecting means for detecting a change in printer status, and a printer status in response to the detection by the detecting means. And non-periodic status reply means for transmitting status information indicating the above to the network interface.

This network printer returns status information to the host computer when the printer status changes.

The preferred embodiment further includes a periodic status reply unit for periodically transmitting status information to the network interface, and a mode selection unit for selecting one of the irregular status reply unit and the periodic status reply unit.

According to this embodiment, it is possible to select whether the status reply is performed periodically or only when the status changes.

[0019]

FIG. 1 shows a configuration of an embodiment of a network printer according to the present invention, together with a host computer connected thereto.

The illustrated printer 1 is connected to an unspecified number (here, three) of host computers 3A, 3B, and 3C via a network interface 5.
The printer 1 includes an interface control unit 7, a main controller 9, a memory 11, and a print engine 13. The memory 11 has a status reply (hereinafter abbreviated as SR) corresponding to each of the three host computers.
Flags 15A, 15B, 15C and SR mode value 1
6A, 16B, 16C and various printer statuses 17 are stored. Further, the memory 11 is provided with a reception buffer 19, an image buffer 21, and the like.

The main controller 9 includes the reception buffer 1
9 for processing the data. The main controller 9 generates a print image by processing data for printing, develops the print image in the image buffer 21, and interprets attribute information included in the data as to which computer the data came from. It also has a function to recognize by doing. With this latter function, the main controller 9 controls the SR function of the interface control unit 7 in response to data relating to the SR function. In general, the attribute information is set in a header section prior to the print image data in each job. Therefore, by submitting a job on the network by putting the address of the name of the host computer which is the sender of the job in this header, it is possible to recognize which computer came from the printer side. Become.

The interface control unit 7 communicates with an unspecified number of computers via the host interface 5. This interface control unit 7
Has a function of receiving data coming from, for example, the computers 3A, 3B, and 3C and writing the data into the reception buffer 19 in the memory 11. Further, it has a function of receiving attribute information interpreted by the main controller 9, recognizing which computer the data belongs to, and storing the corresponding SR flag and SR mode value in the memory 11. In this case, although data can be received from an unspecified number of computers, the computer which has transmitted the information relating to SR among them is registered in the memory in the form of the computers 3A, 3B, 3C. . Further, the interface control unit 7 has an SR function of generating an SR character string based on the printer status 17 stored in the memory 17 and sending the character string to each of the host computers 3A, 3B, and 3C.

The print engine 13 includes the image buffer 2
This is a mechanism for reading a print image from No. 1 and printing an actual image on paper.

The memory 11 stores a printer status 17
Are stored, such as a state such as a standby / busy / error, an error content when an error occurs, an ink remaining amount, presence / absence of paper, selection of a paper path, and a computer requesting SR information. Each SR flag 15A, 15B, 15C, if present and on, means that the SR string should be transmitted to the corresponding host computer, and if it is off or not present, the corresponding SR string. This means that there is no need to send the SR character string to the host computer. Each SR mode value 16A, 16B, 16C indicates whether the SR character string is sent to the corresponding host computer periodically or irregularly. If the value is 0, it is irregularly transmitted (that is, (This is sent only when there is a change in the printer status.) If the value is other than 0, it means that it is sent periodically at the time interval indicated by the value. The printer status 17 is referred to by the interface control unit 7. SR flags 15A, 15
B, 15C and SR mode values 16A, 16B, 16C
Are updated and referenced by the interface control unit 7.

The arrow of the print data in FIG. 1 indicates that the print data from the host computer 3 once enters the reception buffer 19 through the interface control unit 7, and is then taken into the main controller 9 for processing. As a result of this processing, the print image is expanded in the image buffer, and the print engine captures the print image and prints the actual image on paper.

In parallel with the reception of the print data, the interface control unit 7 designates the host computer, which has the SR flags 15A, 15B and 15C and is in the ON state, by using the SR mode values 16A, 16B and 16C. Send the SR string in the manner described. Therefore, at this time, if the SR flags 15A, 15B, and 15C are on, for example, the SR character string is sent to all of the host computers 5A, 5B, and 5C. SR
Flags 15A, 15B, 15C and SR mode value 16A,
The settings of 16B and 16C are performed by the interface control unit 7,
This is performed according to an SR control instruction from the main controller 9. The main controller 9 is connected to each host computer 3
A, 3B, and 3C, determine how to set each SR flag 15A, 15B, 15C and each SR mode value 16A, 16B, 16C according to a command related to the SR function received from the interface control unit 7, To instruct. Note that the setting related to the SR function such as the SR mode value is generally performed by the host computer 3 through, for example, a screen of a user interface in a printer driver or by using utility software.

FIG. 2 shows the operation of the main controller 9.

The main controller 9 controls the reception buffer 1
9, the received data is read (S1). If the read data is raster image data, a raster image is generated from the data (S3). If the read data is a command, the command is interpreted (S4). As a result of the command interpretation, if the command is a command requesting the turning on of the SR function, the SR flag area for the computer designated by the command is set, the SR mode value is set, and the SR flag is turned on. Sends control instructions to interface control unit 7
(S5). If the command requests the SR function to be turned off, an SR control instruction to turn off the SR flag is sent to the interface control unit 7 (S5).
6). Further, when the received command is a command other than the SR function, processing according to the command (for example,
Generation of a text image, generation of a graphic image, etc.) are performed (S7).

The host computers 3A, 3B, 3C
For example, when the printer driver is activated, a command for requesting the SR function to be turned on is sent to the printer 1. Also, the host computer 3A, 3B, 3C does not always need to send this command for requesting the SR function to be turned off.

FIG. 3 shows the operation of the interface control unit 7 which has received an SR control instruction from the main controller 9.

Upon receiving the SR control instruction from the main controller 9, the interface control section 7 requests the state-reply from among an unspecified number of host computers (that is, the above-mentioned SR function on or off). (S11), and if necessary, secures a storage area for the computer (S11), turns on the SR flag 15 corresponding to the requesting computer, and responds. The SR mode value 16 is set to the value specified by the SR control instruction (S12). At this time, the first requested computer is set to, for example, 15A, the next computer is set to 15B, and then the storage area is set to 15C. On the other hand, when the SR control instruction indicates that the SR flag is to be turned off, the SR flag 15 corresponding to the host computer is turned off, and the storage area itself is released as needed (S13).

According to the operation shown in FIGS. 2 and 3, if each of the host computers 3A, 3B and 3C shown in FIG. Flags 15A, 15
B and 15C are turned on. Therefore, after all of the three host computers 3A, 3B, and 3C have started the printer driver at least once, all the SR flags 15A, 15B, and 15C are in the ON state. The SR character string will be transmitted to 3B and 3C.

FIG. 4 shows an interface control unit 7 for sending the SR character string to the host computers 3A, 3B and 3C.
The operation of FIG.

The processing routine shown in FIG. 4 is repeatedly started at predetermined intervals of several seconds. First, the interface unit 7
A process (S21) for sending the SR character string to the host computer 3A is performed. In this process, first, the SR flag 1
5A is checked (S31). If it is off, nothing is performed. If it is on, the SR mode value 16A is checked (S32). When the SR mode value 16A is 0 (that is,
In the case of irregular transmission, it is checked whether or not the printer status 17 has changed since the previous execution of the processing routine (S33). Whether it has changed or not can be determined by, for example, a method of creating an SR character string from the current printer status 17 and comparing the SR character string with the previously created SR character string. As a result, only when the printer status 17 has changed, the SR character string created from the current printer status 17 is transmitted to the network interface 5 with the host computer name corresponding to the flag added to the attribute information (S36). ).

In step S32, the SR mode value 1
If 6A is a value n other than 0 (that is, in the case of periodic transmission), the value of the time counter for counting the transmission cycle (the initial value is equal to n) is reduced by 1 (S34). Next, it is checked whether the value of the time counter is 0 (S35). As a result, only when the value of the time counter is 0, the value of the time counter is reset to the initial value n (S37), and the SR character string created from the current printer status 17 is sent to the network interface 5, The host computer name corresponding to the flag is added to the attribute information and transmitted (S36).

Each computer connected to the network interface 5 sequentially picks up and interprets the attribute information of the information to be transmitted, and reads out the content itself when it determines that the information is requested by itself. By repeating the processing routine shown in FIG. 4 at predetermined time intervals, only the host computer in which the SR flag is on is notified of the printer status when the printer status changes or periodically. Will be.

It should be noted that the SR character string transmitted to the network interface 5 indicates whether the printer is currently printing, and which host computer data. Character code indicating the information of This allows the host computer to show the user a message such as "printing data from another host".

When transmitting the SR character string to the network interface 5, it is not always necessary to add the host computer name corresponding to the SR flag to the attribute information. Otherwise, each computer interprets the broadcast information, and if it determines that the SR string it is waiting for is included in the information or determines that it is the SR string itself, it takes in the information. I just need.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment of a network printer of the present invention.

FIG. 2 is a flowchart showing an operation of a main controller 9;

FIG. 3 is a flowchart showing an operation of an interface control unit 7 receiving an SR control instruction from a main controller 9;

FIG. 4 is a flowchart showing the operation of an interface control unit 7 for sending an SR character string to a host computer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Printer 3 Host computer 5 Network interface 7 Interface control part 9 Main controller 11 Memory 15 Status reply (SR) flag 16 SR mode value 17 Printer status

Claims (8)

[Claims] 1. A network interface for connecting to a plurality of computers via a network, requesting computer identification means for identifying a host computer requesting a status reply, and each of the host computers identified by the identification means A status reply means for transmitting status information indicating the printer status. 2. The requesting computer identification means provides a flag corresponding to each of the plurality of computers,
Means for turning on the status of the corresponding flag in response to data requesting a status reply received from each of the computers, wherein the status reply means checks the status of all the flags. 2. The network printer according to claim 1, further comprising: means for transmitting the status information to each of the host computers corresponding to the flag in an on state. 3. The requesting computer identification means provides a flag corresponding to each of the plurality of computers,
Means for turning on the state of the corresponding flag in response to data for requesting a status reply received from each of the computers, wherein the status reply means determines whether or not the flag is present. 2. The network printer according to claim 1, further comprising: means for checking the status, and if yes, means for broadcasting the status information over a network. 4. A means for detecting that the status reply means has changed the printer status, and means for transmitting the status information to each of the identified host computers in response to the detection by the detecting means. The network printer according to claim 1, comprising: 5. A network interface for connecting to a computer via a network, detection means for detecting a change in printer status, and status information indicating the printer status in response to the detection by the detection means. A network printer comprising: a non-periodic status reply means for transmitting to the computer on the network. 6. A periodic status reply unit for periodically transmitting the status information to a computer on the network, and a mode selection unit for selecting one of the non-periodic status reply unit and the periodic status reply unit. The network printer according to claim 5, wherein 7. A mode setting means for setting the mode value based on a mode value corresponding to the computer and data received from the computer, and the irregular status reply means based on the mode value. 7. The network printer according to claim 6, further comprising: means for selecting one of the periodic status reply means. 8. A computer connected to a plurality of said computers on a network, wherein said mode selection means individually selects one of said non-periodic status reply means and said periodic status reply means for each of said computers. The described network printer.