JPH04227524A - Printing system - Google Patents

Abstract

PURPOSE:To provide the printing system with a high cost-to-effect ratio by providing one print server for a different kind of terminal and plural kinds of print protocol. CONSTITUTION:This system is equipped with plural terminal devices and the print server which is connected to the terminal devices through a network and document data consisting of print command sequences generated on the terminal devices are printed by the print server. In this printing system, the terminal devices has means which give identifiers indicating the kinds of their printing protocol to the document data to be sent out to the print server, which has a protocol converting means which converts the different kinds of print protocol that the terminal devices have into common print protocol.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing system in which a plurality of workstations or personal computers can share a print server.

0002

[Prior Art] In recent years, in the field of workstations and personal computers, LAN (Local A
rea Net-work) and WAN (Wide Ar
ea Network) is becoming popular. As these become more popular, print servers that can be shared by multiple workstations, personal computers, and word processors (hereinafter collectively referred to as terminals) are becoming important because they reduce installation costs and installation space.

A printing system using a conventional print server is configured as shown in FIG. Here, the print server 14 includes a server 15 and a printer controller 16.
, and a printer engine 17. In this printing system, printing is performed using the following steps.

(1) Each of the terminals 11 to 13 sends document data 18 representing the print content of the document to the server 15 via the path 19-a in order to request printing from the print server 14 via the network 10. do. Here, the document data consists of a print command string for describing print contents such as characters, figures, images, etc. of each page of the document.

(2) The print server 14 processes as follows. (a) First, the server 15 transfers the document data to the server 1.
Print spool file section 15 in the file section 151 of No. 5
Temporarily store it in 2. (b) The server 15 reads the stored document data, transmits it to the printer controller 16, and instructs printing. (c) The printer controller 16 processes the received document data and instructs the printer engine 17 to print. (d) The printer engine 17 executes an electrophotographic printing process or a wire dot printing process according to instructions from the printer controller 16, and prints on paper.

[0006] Regarding the above-mentioned prior art, for example,
JP 62-274331, JP 63-75828,
It is described in the publications No. 63-99644 and No. 63-250730.

[0007]

[Problems to be Solved by the Invention] In the above-mentioned prior art, (a) consideration is given to allowing different types of terminals to share a print server, and (b) consideration is given to the ability to write the document data even if the types of terminals are the same. There is no consideration given to sharing the print server when the printing protocols are different.
There is a problem in that it is often not possible to share a print server.

[0008] Therefore, in order to support different types of terminals and different types of printing protocols, it is necessary to prepare separate print servers for each type of terminal and printing protocol, which is said to have a poor cost-effectiveness ratio. There were also problems.

[0009] The above-mentioned Japanese Patent Laid-Open Publication No. 63-75828 discloses a technique for converting print data transferred from a terminal in a server system to suit the printer format of the server system. All of the plurality of terminals have the same data printing format, and are not compatible with different types of terminals.

[0010] An object of the present invention is to provide a printing system with a high cost-effectiveness ratio, which solves the problems of the above-mentioned conventional technology and can support different types of terminals and multiple types of printing protocols with a single print server. Our goal is to provide the following.

[0011]

[Means for Solving the Problems] In order to achieve the above object, a printing system according to the present invention includes a plurality of terminal devices,
In a printing system that includes a print server connected to the plurality of terminal devices via a network, and in which the print server prints document data consisting of a print command string created by the plurality of terminal devices, Each has means for adding an identifier indicating its own print protocol type to document data sent to the print server, and the print server converts different print protocols of the plurality of terminal devices into a common print protocol. It has a protocol conversion means.

According to another aspect, the printing system according to the present invention includes a plurality of terminal devices and a print server connected to the plurality of terminal devices via a network, and prints created by the plurality of terminal devices are provided. In the printing system in which document data consisting of a command string is printed by the print server, each of the plurality of terminal devices has means for adding an identifier indicating its own printing protocol type to the document data sent to the print server. , the print server stores a plurality of command processing programs corresponding to different printing protocols of the plurality of terminal devices;
and means for selecting a command processing program corresponding to the printing protocol in accordance with the identifier added to the document data received from the terminal device.

[0013] In this printing system, a part of the command processing program that can be commonly used for different printing protocols may be shared.

[0014] The print server also includes a secondary memory that stores a plurality of command processing programs corresponding to the different printing protocols, and a secondary memory that reads and stores a command processing program designated by the identifier from the secondary memory. It may also have a main memory.

[0015] According to yet another aspect, the printing system according to the present invention includes a plurality of terminal devices and a print server connected to the plurality of terminal devices via a network. In the printing system in which document data consisting of a print command string is printed by the print server, each of the plurality of terminal devices has means for adding an identifier indicating its own print protocol type to the document data sent to the print server. The print server includes a plurality of command conversion means for converting command groups corresponding to different printing protocols of the plurality of terminal devices into a common command group, and the identifier added to the document data received from the terminal device. and means for selecting a command conversion means compatible with the printing protocol in accordance with the printing protocol.

The print server includes a server having a file unit that receives and stores document data from the plurality of terminal devices, and a printer controller that receives specific document data from the server and processes the print command. , a printer engine unit that performs printing according to instructions from the printer controller, and the printer controller includes a secondary memory that stores a plurality of font sets;
It is also possible to have a primary memory that stores necessary font sets among the plurality of font sets.

Further, the print server includes a server having a file unit that receives and stores document data from the plurality of terminal devices, and a printer that receives specific document data from the server and processes the print command. a controller, and a printer engine unit that performs printing according to instructions from the printer controller, the plurality of command processing programs and the plurality of font sets are stored in a secondary memory in the server, and the printer controller specifies when necessary. The printing program and font set may be received from the server.

Note that a configuration may be provided in which the same processing as for protocol types is performed not only for differences in protocol types but also for differences in character code types.

[0019]

[Operation] The operation of the alternative printing system according to the present invention will be explained below.

[0020] After each terminal creates document data using a document data creation section, it transmits the document data to a printer controller using an in-terminal server communication section.

[0021] After receiving the document data sent by each terminal using the terminal communication unit, the server stores the document data in the print spool file unit in the aforementioned data format consisting of a pair of a print protocol type identifier and a print command string. Store. The server then reads each piece of document data in the print spool file section in an appropriate order and sends it to the printer controller using the printer controller communication section.

In the printer controller, the command processing section processes the document data received by the server communication section within the printer controller as follows. (1) Indicate the print protocol type at the beginning of the document data.
Identification is made using the print protocol identification section. (2) Switching to the command processing program for the identified new print protocol is performed using the print protocol switching section. (3) Process the print command string in the document data (described in the new print protocol type) and instruct the printer engine to print. As described above, even if multiple types of terminals create document data using various types of printing protocols and request printing to the print server, the document data received by the printer controller in the print server Since the printing process can be performed by identifying the printing protocol type and performing command processing that matches the printing protocol, it is possible to provide a printing system with a high cost-effectiveness ratio.

[0023] The operation for different character code types is also similar.

[0024]

[Embodiment] A first embodiment of the present invention will be described below with reference to FIGS. 1 and 2.
This will be explained using a configuration example.

[0025] This printing system includes a network 10 such as a LAN or WAN, and a plurality of terminals, terminal 1 (11) and terminal 2, which can communicate with each other via the network.
(12), ..., terminal N (13) and print server 14
It consists of.

[0026] Each of the above terminals 11 to 13 is connected to network 1.
In order to request printing to the print server 14 via the path 19-a, document data representing the print content of the document is sent via the path 19-a.

The print server 14 includes a server 15, a printer controller 16, and a printer engine 17, and processes as follows. (1) As shown in FIG. 2, the server 15 first transfers the document data received from each terminal to the file section 15 of the server 15.
1 is temporarily stored in the print spool file section 152 in 1. (2) The server 15 reads the stored document data, transmits it to the printer controller 16, and instructs printing. (3) The printer controller 16 processes the received document data and instructs the printer engine 17 to print. (4) The printer engine 17 executes an electrophotographic printing process or a wire dot printing process according to instructions from the printer controller 17, and prints on paper.

The printer controller 16 also includes an intra-printer controller server communication section 161, a command buffer section 162, a command processing section 163, a printer output buffer section 167, and a printer control section 168.

The document data (1521, 1522, etc.) in the print spool file section 152 transmitted by the server 15 is received by the server communication section 161 in the printer controller and stored in the command buffer section 162. The document data in the command buffer section 162 is processed by the command processing section 163.
The drawing data such as characters, figures, images, etc. that are the execution results are processed by the printer output buffer section 16.
7. The data in the printer output buffer section 167 is read by the printer control section 168, converted into a signal in a format that the printer engine 17 can receive, and output to the printer engine 17.

[0030] The following explanation will proceed assuming that the models of terminal 1 and terminal 2 and the printing protocols used by them are in one of the following two cases, but the present invention also applies to other cases as well. The same can be applied.

(Case 1) The models of terminal 1 and terminal 2 are
Model 1 and model 2 are different. Furthermore, the printing protocols used by terminal 1 and terminal 2 are protocol 1 and protocol 2, respectively, which are different.

(Case 2) The models of terminal 1 and terminal 2 are the same, but the printing protocols used by terminal 1 and terminal 2 are protocol 1 and protocol 2, respectively, which are different.

In this printing system, the following components are provided so that terminal 1 (11) and terminal 2 (12), which have different models and different printing protocols, share the print server 14.

(1) Document data creation units 111, 121, . . . , 131 for creating document data consisting of a print protocol type and a print command string in each of the terminals 11 to 13.
and in-terminal server communication units 112, 122, . . . , 132 for transmitting document data 18 to server 15.

(2) The server 15 includes a terminal communication unit 150 for receiving document data 18, a file unit 151 for storing various files, and a print protocol type (1521-a or 1522-a) for storing received document data. ) and a print command string (1521-b or 1522-b) as document data (1521 or 1522) for temporary storage, and each document data ( 1521 and 1522) to the printer controller 16.

(3) The printer controller 16 is provided with an intra-printer controller server communication section 161 for receiving document data.

Furthermore, the command processing unit 163 includes a print protocol identification unit 164 for identifying the print protocol type, and a print protocol switching unit for switching to the command processing programs 1661, 1662, . . . , 1663 for the identified print protocol. A section 165 is provided.

Each component explained in (1) to (3) above operates as follows.

(a) Terminal 1 (11), terminal 2 (12),
..., the terminal 3 (13) is the document data creation section 1 on each terminal.
11, 121, . . . , 131 to create document data consisting of a set of a print protocol type and a print command string written in the print protocol type. Thereafter, the document data is transmitted to the print server 14 using the in-terminal server communication units 112, 122, . . . , 132. here,
Each of the document data creation units 111, 121, . . . , 131 is appropriately prepared according to the model of each terminal, the printing protocol, and the application program for creating print content on the terminal.

(b) After receiving the document data sent by each of the terminals 11 to 13 using the terminal communication section 150, the server 15 stores the above-mentioned data format (print protocol type and print command) in the print spool file section 152. Column pairs).

(c) The server 15 then downloads each document data 1521 and 1522 in the print spool file section 152.
are read in an appropriate order, and the printer controller communication section 1
53 to the printer controller 16. Here, the order of reading and transmitting is determined by the server 15 in consideration of the order of reception from each terminal, the paper size used for each document data, the total number of printed pages of each document data, etc.

(d) The printer controller 16 uses the server communication section 161 in the printer controller to send document data (1521 and 1522) received from the server 15.
is temporarily stored in the command buffer section 162. The command processing section 163 processes the document data in the command buffer section 162 as follows. (i) The print protocol type at the beginning of the document data 1521 and 1522 is identified using the print protocol identification unit 164. (ii) Switching to one of the command processing programs 1661, 1662, . . . , 1663 for the identified new print protocol type (protocol 1 or protocol 2) is performed using the print protocol switching unit 165.

Since the print spool file section 152 is provided, the following effects can be obtained. (1) Printer controller 16 and printer engine 1
7 is already in use for printing other document data, etc., and even if it is not free, the server 15 accepts print requests from one or more terminals and fills the print spool file section 152. It can be stored in the file section 152.

(2) Furthermore, the same server 15 can receive document data created by multiple types of terminals using various types of printing protocols.

[0045] Each terminal 11, 12, 13, etc. is connected to the server 15.
The server 15 requests the next service, and the server 15 executes the service. (i) Request to print document data (ii) Interrupt/continue printing of document data that has already been requested to print (
iii) Forced termination of printing of document data that has been requested to be printed (i)
v) Inquiry regarding the printing status of the print-requested document data (v) Print completion report from the server 15 to the print requesting terminal at the time of detecting the print completion of the print-requested document data (
vi) Changing the print waiting order of print requested document data in the print spool file section 152 In this embodiment, the first document data 1521, the second document 152
Document data of the second class are connected to one print queue regardless of their print protocol type. However, a method (hereinafter referred to as print queue method 2) may be used in which separate print queues are provided depending on the type of terminal or print protocol, and each document data is connected to the corresponding separate print queue. Note that each document data (mentioned in 1.
521, 1522) is the print command string (1521 described above)
-b, 1522-b), and print protocol type (
The above-mentioned 1521-a and 1522-a) are not included. This print queuing method 2 has the following characteristics compared to the method (hereinafter referred to as print queuing method 1) that uses the same print queue regardless of the print protocol described above.

(1) When the number of new terminals and types of print protocols increases, it is necessary to add a print queue. Because of this expansion, extra processing and time are required compared to print queue method 1, and management is also complicated.

(2) Although most of the print queues contain almost no document data, only some of the print queues are connected to document data corresponding to the maximum number of connections. There may be a rush of print requests from various terminals. In this case, the terminal or its user is forced to wait for a print request, reducing the print throughput of the printing system.

(3) Since print requests from each terminal are received in a distributed manner over a plurality of print queues, the server 15 sends the print requests to the printer controller 1 in the order in which they are received from the terminals.
It is difficult to issue a print instruction to 6. Even if it were possible, the processing and management would be complicated.

(4) When the server 15 receives a print request from a terminal, the server 15 analyzes and identifies the print protocol type in each document data received from the terminal, and then adapts the document data to the print protocol type. You need to connect to the print queue that you created.

(5) When transmitting each document data in each print queue to the printer controller 16 and requesting printing,
It is necessary for the server 15 to check the type of each print queue and to transmit the type of the print queue to the printer controller 16 before transmitting the document data.

(6) As shown in (4) and (5), in the print queue method 2, the server 15 needs to perform processing and management according to the print protocol type.
This is not necessary in the in-difference queuing method 1.

As a multi-print protocol switching control system for the printer controller 16 to accept and process multiple types of print protocols, the following three systems have been devised as shown in FIG. (a) [Method 1] Exchange method of protocol-compatible command processing programs (b) [Method 2] Command conversion method (c) [Method 3] Individual program part exchange method for command interpretation, etc. Method 1 is a method for exchanging command processing programs for each printing protocol. A command processing program is prepared in advance in the printer controller 16 or server 15, and when the print protocol identification unit 164 detects that the print protocol type has been changed, the command processing program is switched to the command processing program for that print protocol, The embodiments described above mainly employ this method.

Method 2 is a method in which the command processing unit 163 interprets commands corresponding to the print protocol, converts print commands in each document data into common commands, and then executes the common commands. Therefore, a command conversion table and a command conversion program corresponding to each print protocol are prepared in advance for each print protocol, and these are used to convert the above-mentioned commands.

Method 3 is an intermediate method between Method 1 and Method 2, in which a command interpretation section and an individual drawing processing section that change according to each printing protocol are separately prepared, and only these individual sections are used. This eliminates the need to replace the common drawing processing unit that can be replaced and used in common.

In method 2, if the command system for each print protocol is different from the command system for the common command, conversion to the common command may not be possible. Even in such a case, there are many printing protocols that can be handled by adding commands that cannot be converted to common commands to common commands.

However, if there is a large difference between the command system for common commands and the command system for each print protocol (for example, one is an escape sequence command for printer control and the other is a Post Script
etc.), conversion is difficult. Even if conversion is possible, the command conversion table and command conversion program for conversion will become complicated, and the command conversion time (included in the command processing time after conversion in FIG. 4) will increase.

On the other hand, in methods 1 and 3, a command processing program, command interpretation section, and individual drawing section corresponding to each printing protocol are prepared, so that any printing protocol can be supported.

Therefore, in the column of multi-printing protocol support ability in FIG. 4, methods 1 and 3 are rated ○ (good).
However, method 2 is assumed to be △ (there may be some inconveniences).

[0059] Accordingly, method 2 is used for printing protocols within a range where the above-mentioned inconvenience does not occur.

As described above, in this embodiment, even if multiple types of terminals create document data using various types of printing protocols and request the print server to print it, as described above, the print data is not stored in the print server. By identifying the print protocol type of the document data received by the printer controller, and performing command processing that matches the print protocol,
Since printing processing can be performed, a printing system with a high cost-effectiveness ratio can be provided.

Next, a second embodiment of the present invention will be explained using the configuration example shown in FIG.

In the first embodiment described above, command processing programs 1661, 1662, . . . for each printing protocol are used.
1663 resides in the main memory (primary memory), the main memory capacity increases in order to support a large number (M) of printing protocols. for example,
Assuming that the capacity of the command processing program per printing protocol is 256 kB (kilobytes) and M is 10,
To store the program, 2560 kB of main memory is required.

By the way, when printing one document, only one print protocol is used at the same time, so it is not necessary to keep all M command processing programs resident in the main memory.

In this embodiment, in order to solve the above problem of increased memory capacity in the first embodiment, a file section (secondary memory) 16A is provided in the printer controller 16, and commands for each print protocol are stored in the file section (secondary memory) 16A. Processing programs 16A1, 16A2, . . . , 16A3 are stored therein.

Further, only the command processing program for the print protocol selected at each point in time is stored in an area called a specific print protocol compatible command processing section 169 in the main memory, thereby reducing the amount of main memory used. As a result, even if M (=10) printing protocols are supported, only one main memory area is required to store the command processing program, as in the specific printing protocol compatible command processing unit 169. That's fine. In the above example, 256 kB would be sufficient.

In this embodiment, the printing protocol is switched as follows.

(1) Print protocol type 1521-a, 1522- at the beginning of document data 1521, 1522
The print protocol identification unit 164 in the command processing unit 163 identifies the print protocol a.

(2) When the command processing unit 163 detects that the print protocol has been changed, it activates the print protocol switching unit 165.

(3) The print protocol switching unit 165:
The command processing program corresponding to the print protocol after switching is stored in files 16A1, 16A2,
..., 16A3, and is loaded into the specific print protocol compatible command processing section 169.

(4) The print protocol switching unit 165 completes the process, and the command processing unit 163 uses the program loaded into the specific print protocol compatible command processing unit 169 to interpret and execute the print command for the new print protocol. I will do it.

[0071] In order to improve the printing throughput in the print server, the printer output buffer section 16
7 is configured as a page buffer memory unit for a plurality of pages, and receives the document command from the server 15, performs drawing processing on each page buffer by the command processing unit 163 in the printer controller 16, and performs processing by the command processing unit 163. It is possible to employ a technique of processing print instructions for each page buffer that has been rendered in parallel. Regarding the technology of this parallel processing, Japanese Patent Application No. 158481/1983 and Japanese Patent Application No. 1/1999 filed earlier by the applicant
No. 164637.

When the above parallel processing technique is applied to this embodiment, the processing of the command processing section is executed as the following two types of tasks.

(a) [Drawing Task] Draw processing is performed for each page buffer until a page end condition such as a page break is detected. When a page end condition is detected, drawing for that page buffer is ended, and a task called a print task is started for that page buffer for which drawing has been completed.

(b) [Print Task] The print task instructs the printer engine 17 to print the page buffer for which drawing has been completed.

In this case, switching the print protocol involves switching from a drawing task for the original printing protocol to a drawing task for the new printing protocol. The procedure for this is shown in Figure 6 using PAD (Problem Analyzes).
is Diagram).

In FIG. 6, the drawing task 51 performs processing for an original print protocol as described above. The drawing task 51 first initializes (5
11), the document data processing 512 is repeated.

Document data processing 512 repeats command interpretation 514 and command execution 515 on the document data until the end of the document is detected (513). Here, the print protocol type (1521-
a and 1522-a) are also handled as commands similar to the print command sequence (in FIG. 6, they are referred to as print protocol specification commands), and processing is proceeding.

That is, the following processing is performed depending on the result of command interpretation 514.

(a) If the command is for specifying a print protocol (516), it is checked whether the print protocol type has changed from the original protocol, and if it has changed, the print protocol is switched, which is called a print protocol control task. (517).

(a) If the command is for character drawing (51
8) Perform character drawing processing.

(c) If the command is for drawing figures (51
9) Perform graphic drawing processing.

(d) If the command is something else (5
1A), perform other processing corresponding to the command.

After starting the print protocol control task (5
17) The process is transferred to a task dispatcher, which selects the print protocol control task as the next task to be executed and starts the process (51B).
.

The print protocol control task 52 issues a task forced termination macro 521 and a task deletion macro 522 to the drawing task for the original print protocol, so that the specific print protocol compatible command processing unit 16
The program for the original drawing task 51 is deleted from 9.

Next, the first printing protocol control task 5
2 is about the drawing task for the new printing protocol.
By issuing the task generation macro 523 and task activation macro 524, the command processing program corresponding to the new print protocol after switching is executed in the file section 16A.
The drawing task 16A1, 16A2, .

The early print protocol control task 52 then issues a task end macro 525 and ends the process.

[0087] When the print protocol control task 52 completes its processing, processing shifts to the task dispatcher 526. The task dispatcher selects the drawing task 53 for the new printing protocol as the next task to be executed, and starts processing.

Drawing task 53 for new printing protocol
After initializing various parameters (531), the document data processing 532 is repeated. The document data processing 532 repeats command interpretation and command execution for each piece of document data until the end of the document is detected.

The basic processing procedure of the drawing task 53 is the same as that of the drawing task 51. The difference is that the target printing protocols are different.

The procedure shown in FIG. 6 can be changed in the following two items.

(1) [Make the task generation macro and task macro unused by making the task control block resident in the main memory] (i) Task control block for managing tasks such as drawing tasks (the 63-158481 and Japanese Patent Application No. 1-164637), the task deletion macro issue 522 and task creation macro issue 523 are removed from the processing of the print protocol control task 52.

(ii) In this case as well, the command processing program corresponding to each drawing task is stored in either the main memory or the file section. This point is the same as the case where this change is not made.

(2) [Changing the timing of loading the command processing program] (i) Changing the timing of loading the command processing program corresponding to the drawing task from the file section to the main memory using the task generation macro implemented in FIG. Change from runtime to one of the following:

■ When a task startup macro is executed ■ When a task dispatcher is executed (ii) The change in the load timing in (i) is made by changing the unused task generation macro and task termination macro in (1) above. Even if you don't have one, you can still do it.

(iii) Also, as the loading time, the above 3
Regardless of which method is adopted, the following common steps are executed during the loading process.

[Load processing procedure] ■ Check whether the command processing program to be loaded (referred to as program A) already exists in the main memory.

■ If there is, finish the loading process.

■ If not, check whether there is a free area necessary to store the program A in the main memory.

■ If there is a free area, load program A from the file section to the main memory.

■ If there is no free area, create a free area necessary to store program A in the main memory, and then load program A from the file section to the main memory.

According to this embodiment, since the main memory capacity of the printer controller 16 is smaller than that of the first embodiment, the same effects as the first embodiment can be obtained with a printing system having an inexpensive configuration. I can do it.

Next, a third embodiment of the present invention will be explained using FIG. 7. In this embodiment, the following components are added to the second embodiment.

(1) There are multiple (J) font sets in the file section 16A, that is, font set 1 (16D).
1), font set 2 (16D2), . . . , font set J (16D3) are stored.

(2) A new font set main memory area 16C is created in the printer controller 16. This font set main memory area 16C contains a plurality of (I) font sets, that is, font set m1 (16
C1), font set m2 (16C2), ..., font set mI (16C3) can be stored.

(3) Here, I<J, so that only a part (I pieces) of the total font sets (J pieces) supported by this printer controller 16 are stored in the main memory, and the font set The aim is to reduce the amount of main memory installed and reduce costs.

(4) The command processing unit 163 executes the font set specification command received from the server,
A font set switching section 16B is provided for switching font sets within the printer controller.

In the printer controller 16 using the above added components, the font set switching section 16B performs font set switching processing as shown in FIG.

(a) In the font set switching process, the font set No. which is the unique number of the font set to be switched next is selected. Processing is performed using n as an input parameter. (b) The font set switching process first determines whether or not the font set n exists in the main memory (71).
.

(c) If it is determined in the process 71 that the font is not in the main memory, the font set main memory area 16C
It is determined whether there is an empty fixed-size font set area (72).

(d) If it is determined in step 72 that there is an empty fixed size font set area, font set n is loaded into this empty fixed size area. Here, loading means copying the contents of font set n in the file section 16A to the free fixed size area in the main memory (73).

(e) If it is determined in step 72 that there is no vacant fixed-size font set area, the following steps 74, 75, and 76 are performed.

(i) Font set main memory area 1
Font set No. of the least frequently used font set in 6C. Search for m (74).

(ii) If necessary, unload the dot image development information for font set m to the save area for font set m in the file section 16A (
75). Here, the dot image development information refers to the font set m described in an expression format other than the dot image format, such as font outline information called an outline font or vector font, or image compression information. The result of dot expansion from the representation format to the dot image format. When using a font set with a representation format other than the dot image,
Character drawing is performed by creating this dot image development information and copying it to the printer output buffer section 167.

(iii) Next, in the area for font set m in the font set main memory area 16C,
Load font set n (76).

(f) Finally, the parameters corresponding to font set n are set as parameters for the current font set (the font set selected and used by the command processing 163 at that time) (77). Here, the parameters for the current font set are:
■Font set No. and (2) the start address of the font set n in the font set main memory area 16C.

Although the explanation in FIG. 8 has been made assuming that all font sets have the same fixed size, even if the required memory size differs depending on each font set, Treat the size as the fixed size, or
By allocating a row of small-capacity unit memory buffers to each font set, and acquiring and releasing the required number of rows of unit memory buffers during font set switching processing,
It can be processed in the same way.

According to this embodiment, the print server can support multiple fonts with a small main memory capacity.

Note that when supporting multiple printing protocols, it is often necessary to change the contents of the supported font set depending on each printing protocol. However, according to the present embodiment, it is possible to deal with such a case, and therefore it is possible to provide an easy-to-use print server.

Next, a fourth embodiment of the present invention will be explained using FIG. 9. In this embodiment, in order to support multiple printing protocols, the location of the command processing program for each printing protocol is transferred from the file section 16A in the printer controller 16 in the second or third embodiment to the server 1.
This is a replacement for the file section 151 in 5.

This embodiment is characterized by the following two points.

■ As shown in FIG. 9, a command processing program storage file section 154 is provided in the file section 151 of the server 15, and command processing programs 1541, 1542, . . . , 1543 for each print protocol are stored therein.
Store.

[0122] The command processing section 163 of the printer controller 16 is provided with a printing protocol identification section 164, a printing protocol switching section 165, and a specific printing protocol compatible command processing section 169.

In this embodiment, in the configuration shown in FIG. 9, printing protocols are switched as follows.

(1) Print protocol type 1521-a, 1522- at the beginning of document data 1521, 1522
The print protocol identification unit 164 in the command processing unit 163 identifies the print protocol a.

(2) When the command processing section 163 detects that the printing protocol has been changed, it starts the printing protocol switching section 165.

(3) The print protocol switching unit 165:
A request is made to the server 15 to send a command processing program for a new print protocol (assumed to be print protocol n) via the server communication unit 161 in the printer controller, and the process shifts to a wait state called a program reception wait state.

(4) The server 15 reads the command processing program for print protocol n requested by the printer controller 16 from any one of the command processing program storage file sections 1541, 1542, . . . Controller communication section 153
The data is sent to the printer controller 16 via the printer controller 16.

(5) The printer controller 16 receives the command processing program for the printing protocol n via the printer controller internal server communication section 161, stores it in the specific printing protocol compatible command processing section 169, and then executes the command processing program for the printing protocol n. The print protocol switching unit 165 is released from the program reception waiting state.

(6) The print protocol switching unit 165 ends the process, and the command processing unit 163 interprets and executes commands for the new print protocol using the program in the specific print protocol compatible command processing unit 169. .

Furthermore, in this embodiment, the file section 16A in the printer controller 16 in the third embodiment is
Multiple font sets (16D1,1
6D2, . . . , 16D3) can be stored in the file unit 151 within the server 15 to support multi-fonts.

According to this embodiment, the multi-printing protocol can be supported using a small main memory similar to the second embodiment without providing a file section in the printer controller 16. It is possible to provide a print server that is even cheaper than the embodiments or the third embodiment.

[0132] In the above embodiment, the print protocol and font set are specified by the server incorporating the print protocol type and print command into part of the document data and sending it to the printer controller. . The same method can be applied to the case where these specifications can be made by key input from the user operation panel on the printer controller.

Next, a fifth embodiment of the present invention will be described. In this embodiment, in the first to fourth embodiments,
Each terminal 11, 12, 13, etc. creates document data using one of a plurality of types of character codes, and the print server 14 prints the document data. Examples of supported character codes include ASCII (A
merican national standard
Code for Information Int
erchange), JIS (Japanese In
industrial Standard) code, shift JIS code, EBCDIC (Extended Bi
Nary Coded Decimal Interc
There is a hang code).

In this embodiment, the following functions are added to the first to fourth embodiments.

(1) Each of the terminals 11, 12, 13, etc., in addition to the print protocol type, preferably adds a character code type in front of the print protocol type to document data.
It is created by each document data creation section 111, 121, 131, etc.

[0136] After that, each terminal transmits the document data using the server communication section 112, 122, 132, etc. within each terminal.
It is sent to the print server 14.

(2) Server 15 in print server 14
sends the received document data (consisting of character code type, print protocol type, and print command string) to the printer controller 16.

(3) The printer controller 16 analyzes the character code type in the document data received from the server 15. If the character code type is the initial value or the previous value (value in the previous document data), after identifying the print protocol type, the process proceeds in the same manner as in the first to fourth embodiments.

(4) If the character code type is neither the initial value nor the previous value, the printer controller 16 switches the command processing unit 163 to one corresponding to the character code type and proceeds with the process.

[0140] This switching is realized by one of the following methods.

(i) [Method using character code conversion] When processing each character code one by one, convert each character code (belonging to a certain character code type) to a common character code while referring to a conversion table. do. This character code conversion is performed by a character code conversion section added to the command processing section 163. The command processing section uses the converted common character code to thereafter execute the processing of the command processing section 163.

(ii) [Method of replacing the character code processing part] The part that processes character codes in the command processing section 163 (abbreviated as character code processing part: it is advantageous from the point of view of extensibility to implement it by a program). A plurality of parts are prepared in advance for each character code type, and the character code processing part is switched to one that matches the character code type according to the character code type.

There are two ways to implement this switching: (a) The entire command processing unit (preferably created by a program from the point of view of extensibility) is switched according to the character code type.

(a) A branch logic corresponding to the character code type is provided in the character code processing section in the command processing section.

The above method (i) requires less program capacity and hardware (circuit) than method (ii), but
It is necessary to perform extra processing such as character code conversion, and the command processing time tends to be longer than method (ii).

Note that the character code conversion in method (i) can be performed by the server 15 instead of by the printer controller 16 as described above. In this case, after the server 15 analyzes the character code type in the document data, it converts each next code into a common character code. The method of character code conversion by the server 15 is method (i
) is similar to the method in which the printer controller 16 converts character codes. The document data written in the common character code converted by the server is sent to the printer controller 16. The printer controller 16 processes the document data written in the common character code as follows.
The process proceeds in the same manner as in the first to fourth embodiments.

(5) Print protocols are roughly divided into the following two types. (a) A print document (the print command string) is described as a string of printer control command character codes and control codes. Control codes are often written as escape sequences that extend character codes. Conventionally, many printers have adopted this printer control command. A typical example is Hewlett Packard
systems' PCL (Printer Com
mand Language) and Epson's ESC/
There are P etc.

(b) Page description language A print document is expressed as a program written in a programming language. A typical example is Adobe Systems.
Intcorporated's Post Scri
Examples include PT and Interpress from Xerox.

[0149] In the above printing protocol (a), the control code may take the same code (bit pattern) among a plurality of supported character code types. In this case, the command processing unit 163
There is no need to convert character codes or switch command processing units for the entire program. That is, it is only necessary to convert the character code or switch the command processing section for only some of the character expansion sections of the command processing section 163.

According to this embodiment, even if the character code types are different in addition to the print protocol types, printing can be performed using the same print server. Therefore, the cost performance of the print server system can be further improved.

[0151] By making all the functions of the server 15 the functions of the printer controller 16, the server 15
It is also possible to integrate the functions of the printer controller 16 and the printer controller 16 to realize a print server 14 that does not include the server 15 in terms of hardware appearance. In this case, server 1
5 (consisting of a CPU, main memory, file section, etc.), the network control section for LAN, WAN, etc. (corresponding to the terminal control section 150) can be left in place, and the rest can be omitted, reducing the cost of the print server 14. can be significantly lowered.

[0152] Furthermore, the printer controller 16 can also be incorporated into the server 15. In this case, server 1
A printer controller board (a board on which the printer controller 16 is mounted) is directly connected to, for example, an input/output bus line in 5. The printer controller 16 can omit the part that controls communication with the server and the file part. An example of a part that controls communication with the server is the SC
SI (Small Computer System I)
interface), Centronics, RS-232C
There are circuits and driver programs for each communication interface such as , Ethernet, and Token Ring. The print server 14 having this configuration can also be made smaller and its cost can be reduced.

[0153]

[Effects of the Invention] According to the present invention, multiple types of terminals can create document data using various types of printing protocols.
Even if a print request is made to the print server, the printer controller in the print server identifies the print protocol of the received document data as described above, and performs the print process by processing commands that match the print protocol. Therefore, it is possible to provide a printing system with a high cost-effectiveness ratio.

Another advantage is that the print server can support multiple printing protocols and multiple fonts in an inexpensive printing system using a small main memory capacity.

[0155] When supporting multiple printing protocols, it is often necessary to change the contents of the supported font set according to each printing protocol, but according to the present invention, such cases can also be handled. This also has the effect of providing an easy-to-use print server.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a configuration example of a first embodiment of the present invention.

FIG. 2 is a block diagram showing the detailed configuration of the print server shown in FIG. 1;

FIG. 3 is a block diagram showing the configuration of a conventional system.

FIG. 4 is an explanatory diagram for explaining a multi-print protocol switching control method in the first embodiment.

FIG. 5 is a block diagram showing a configuration example of a second embodiment of the present invention.

FIG. 6 is an explanatory diagram for explaining a print protocol switching control procedure in a second embodiment of the present invention.

FIG. 7 is a block diagram showing a configuration example of a third embodiment of the present invention.

FIG. 8 is an explanatory diagram for explaining a font set switching control procedure in a third embodiment of the present invention.

FIG. 9 is a block diagram showing a configuration example of a fourth embodiment of the present invention.

[Explanation of symbols]

10...Network, 11...Terminal 1, 12...Terminal 2, 1
3...Terminal N, 14...Print server, 15...Server, 1
6...Printer controller, 17...Printer engine,
151...File section, 152...Print spool file section, 1521-a, 1522-a...Print protocol type,
152-b, 152-b...print command string, 163...command processing section, 164...print protocol identification section, 165
...Print protocol switching section, 16B... Font set switching section, 167... Printer output buffer section, 168...
Printer control unit.

Claims (9)

[Claims] Claim 1: A method comprising: a plurality of terminal devices; and a print server connected to the plurality of terminal devices via a network; document data consisting of a print command string created by the plurality of terminal devices is printed by the print server; In the printing system, each of the plurality of terminal devices has means for adding an identifier indicating its own print protocol type to the document data sent to the print server, and the print server A printing system comprising a protocol conversion means for converting different printing protocols into a common printing protocol. 2. A method comprising: a plurality of terminal devices; and a print server connected to the plurality of terminal devices via a network, wherein document data consisting of a print command string created by the plurality of terminal devices is printed by the print server. In the printing system, each of the plurality of terminal devices has means for adding an identifier indicating its own print protocol type to the document data sent to the print server, and the print server The method includes means for storing a plurality of command processing programs corresponding to different printing protocols, and means for selecting a command processing program corresponding to the printing protocol according to the identifier added to the document data received from the terminal device. A printing system characterized by: 3. The printing system according to claim 2, wherein a part of a command processing program that can be commonly used for different printing protocols is shared. 4. The print server includes a secondary memory that stores a plurality of command processing programs corresponding to the different printing protocols, and reads a command processing program designated by the identifier from the secondary memory and stores the command processing program. 3. The printing system according to claim 2, further comprising a main memory. 5. A method comprising a plurality of terminal devices and a print server connected to the plurality of terminal devices via a network, wherein document data consisting of a print command string created by the plurality of terminal devices is printed by the print server. In the printing system, each of the plurality of terminal devices has means for adding an identifier indicating its own printing protocol type to document data sent to the print server, and the print server is configured to add an identifier to the document data sent to the print server, and the print server a plurality of command conversion means for converting command groups corresponding to different print protocols into a common command group; and a command conversion means for converting commands corresponding to the print protocol according to the identifier added to the document data received from the terminal device. A printing system comprising: means for selecting. 6. The print server includes a server having a file unit that receives and stores document data from the plurality of terminal devices, and a printer that receives specific document data from the server and processes the print command. The printer controller includes a controller, and a printer engine unit that performs printing according to instructions from the printer controller, and the printer controller includes a secondary memory that stores a plurality of font sets;
6. The printing system according to claim 1, further comprising a primary memory for storing necessary font sets among the plurality of font sets. 7. The print server includes a server having a file unit that receives and stores document data from the plurality of terminal devices, and a printer that receives specific document data from the server and processes the print command. a controller, and a printer engine unit that performs printing according to instructions from the printer controller, the plurality of command processing programs and the plurality of font sets are stored in a secondary memory in the server, and the printer controller specifies when necessary. 3. The printing system according to claim 2, wherein said printing program and font set are received from said server. 8. Each of the plurality of terminal devices further includes means for adding an identifier indicating its own character code type to document data sent to the print server, and the print server is configured to 6. The printing system according to claim 1, further comprising character code conversion means for converting different character code types into a common character code. 9. Each of the plurality of terminal devices further includes means for adding an identifier indicating its own character code type to document data to be sent to the print server, and the print server is configured to Claims 1 and 2 further comprising means for exchanging a plurality of character code processing parts selected according to different character code types.
or the printing system described in 5.