JP2844538B2 - Printer control device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printer control device such as a laser printer, and more particularly to prevention of data loss after a software change request.

2. Description of the Related Art In order to cover a computer network conventionally supported by a plurality of different types of printers with as few printers as possible, it is intended to execute each command of each type of different type of printer by a software change method. ing.

In a conventional printer control device, there is no function of changing software by a communication command with a host computer, and the software is changed by an operation panel or the like attached to the printer body. In recent years, software change has been performed by a communication command. In this case, however, only a specified software can be used to create only one document for a long time.

However, in the current document creation, one document is created by using different kinds of processing software in the printer control device, and one document is connected to a network.
It is desired that various applications can be used by using one printer. In this case, different types of software data strings are successively sent to the laser printer or the like via the host interface with software change commands as delimiters.

The input buffer control of a laser printer or the like to which such a data string is sent includes command data for immediately interpreting and executing data received from the host computer, such as a system reset command or a status request command that differs depending on the software, and a command. Then, it is separated into other data, text data for printing, image data, and the like. The command data is interpreted immediately.
After execution, data other than the command data is temporarily stored in the input buffer and then sent to the next control in accordance with the printing speed of the printer. The software change request command is not usually immediately interpreted, but is stored in the input buffer. Because the software
The data put in the input buffer before the change request command is an example of data for different kinds of software before the software change, and should be processed before the software change. For this reason, software
The change request command is also stored in the input buffer like normal data.

When a software change request command is recognized while the data stored in the input buffer is sequentially read and interpreted by the interpreter and executed, the program jumps to the designated software initialization routine and changes. Entrust the entire control to the software. Then, the new software initializes the system, starts communication with the host computer, and performs a printing operation.

[Problem to be Solved by the Invention] In the input buffer control of the laser printer or the like, software stored in the input buffer
When recognizing a change request command and initializing the system, the input buffer is also initialized. For this reason, the data after the software change request command stored in the input buffer by the software before conversion is erased, resulting in a data loss.

In order to solve this problem, a buffer is provided on the host computer side, and a delay time is set for data transmission immediately after transmitting the software change request command,
In some cases, a method of resuming data communication after a software change of the printer control device is completed is adopted.

However, the method of providing a buffer on the host side requires that a means for recognizing a software change request command of a printer to be used and a means for controlling a waiting time at the time of software change be added to the host side.
The system construction on the host side becomes troublesome. In many cases, the above measures cannot be taken on the host side, and it has been difficult to completely eliminate the problem of data loss.

Therefore, it is necessary to take measures against data loss at the time of software change in the printer, but conventionally, such measures could not be taken in the printer. The reason is that the immediate processing command and the like are not put in the input buffer, the software change request command is stored in the input buffer, and the input buffer is also initialized together with the system initialization immediately after the software change. It depends. The latter inconvenience can be solved by limiting the input buffer area for each different software in advance so that it can be used as it is even after the software change. However, the inconvenience due to the former reason cannot be simply solved.

That is, until the routine for sequentially reading and developing the data stored in the input buffer and recognizing the software change request command recognizes the software change request command, the software immediately before executing the software change executes the immediate processing command. For this reason, if the data sent after receiving the software change request command should not be processed immediately by the software after the software change, but is data for normal processing, this data is used before the software change. May be immediately processed by this software and result in data loss. The most prominent example is when there is an image data transfer following a software change request command. Since all data codes are predicted for the image data, the image data transfer command receives the same processing as the immediate processing command, and the subsequent image data is not immediately processed. It is sufficient that the immediate processing command and the image data transfer command can be unified by each software, but it is impossible to unify by the software used as the emulation of the existing printer. Therefore, if the software before and after the software change has different recognition of image data, the image data for the software after the software change is immediately processed by the software before the software change. And
As a result, data loss may occur.

In order to eliminate the data loss, it is conceivable to store an immediate processing command in the input buffer or to have a processing routine for input buffer control for each software, but there is a disadvantage that the program becomes enormous.

SUMMARY OF THE INVENTION The present invention has been made in order to solve such a disadvantage, and an object of the present invention is to provide a printer control device capable of eliminating data loss at the time of software change without adding a buffer to a host. Is what you do.

[Means for Solving the Problems] A printer control device according to the present invention comprises software
An auxiliary buffer for storing a data string continuously transmitted from the host computer after a transmission stop request is made to the host computer when the change request is made and before the host computer actually interrupts data transmission; The data to be processed is separated by setting a software change request as a delimiter.

[Operation] In the present invention, data sent after the software change request command is sent to the printer is stored in the auxiliary buffer, the system is recognized upon recognition of the software change request command, and the input buffer is also initialized. During the conversion, the data stored in the auxiliary buffer is stored, and the data to be processed is separated by a software change request as a delimiter.

FIG. 1 is a block diagram showing a configuration of a laser printer according to an embodiment of the present invention. In the figure, 1 is a host computer for sending character information and image information, 2 is a control unit of a laser printer, 3 is an engine for printing image image information generated by the control unit 2 on paper, and 4 is recorded on a font card or the like. And an external information input unit for inputting external information.

The control unit 2 includes a host interface 5, a CPU 6, a program ROM 7, a RAM 8, a font RAM 9, a nonvolatile RAM 10, and a scaling unit 1.
1, an operation panel 12, an option interface 13, a video control unit 14, and an engine control unit 15.
Connected by The video controller 14 and the engine controller 15 are connected to the engine 3 via a laser printer video interface (hereinafter, LPVI) 17.

The host interface 5 is an interface for connecting the host computer 1 and the control unit 2,
Consists of RS232C, Centronics specifications, etc.

The CPU 6 consists of 16 bits or 36 bits, and the data processing unit 61
And a central processing unit having an image information processing unit 62 and generally controlling the entire control unit 2. Program ROM7 is CPU6
The microcode for controlling is stored.

The RAM 8 is a large-capacity random access memory, and includes a system memory 81, an input buffer 82 including a ring buffer, an auxiliary buffer 83, a page buffer 84, a font file 85, a micro file 86, an image file 87,
Print control file 88 and video buffer 89
Used for etc.

The font ROM 9 stores font data for converting character information transmitted from the host computer 1 via the host interface 3 into image information. The nonvolatile RAM 10 stores information for controlling the operation state of the printer after the power is turned on.

The scaling unit 11 performs scaling processing of the image information. The video controller 14 converts the image data stored in the video buffer of the RAM 8 with the bus width (16 bits or 32 bits) of the CPU 6 into serial data, and sends it to the engine 3 via the LPVI 17. The engine control unit 15 detects the state of the engine 3 by a bidirectional serial signal via the LPVI 17 and sends a command to control the engine 3.

First, the outline of the operation of the laser printer configured as described above will be described with reference to the block diagram in FIG. 2 showing the relationship between each memory and the flow of data processing.

A data string continuously transmitted from the host computer 1 is stored directly in the auxiliary buffer 83 via the data storage processing unit 51 of the host interface 5 or temporarily in the auxiliary buffer 83, and then stored in the input buffer 82. The data stored in the input buffer 82 is stored in the data processing unit of the CPU 6.
The data is extracted by 61 and registered in the memory area of the RAM 8 according to the type of data. That is, the print sequence control information such as the specification of the paper transport path and the number of prints is registered in the print control file 88, the page layout information such as the relationship between the print data and the print position is stored in the page buffer 84, and the image information is stored in the image file 87. To
Downloaded fonts are registered in a font file 85, and overlay information and the like are registered in a microfile 86, respectively.

The image information processing unit 62 of the CPU 6 stores an image file 87 and a font file 8 in accordance with the contents of the page buffer 84.
Read out the contents of 5 and font ROM 9 and video buffer 8
Expand to 9. When one page of print data is developed in the video buffer 89, the engine control unit 15 activates the engine 3 via the LPVI 17 according to the contents of the print control file 88. When the engine 3 reaches the image recording timing, the video data expanded in the video buffer 89 is sent to the engine 3 via the video control unit 12 and the LPVI 17,
The sent video data is printed on printing paper by the engine 3.

Next, the operation when storing data in the input buffer 82 and the auxiliary buffer 83 and the operation when reading data from the input buffer 82 and the auxiliary buffer 83 in the above processing operation will be described with reference to the flowcharts of FIGS. It will be described with reference to FIG.

When storing data in the data storage processing unit 51, the third
As shown in the figure, when data is sent from the host computer 1 to the control unit 2, the data storage processing unit 51 of the host interface 5 is activated (step S301), and the host computer 1 controls the printer every time data is transmitted. Part 2
Then, it is determined whether or not a data transmission stop request is being made (step S302). When the data transmission stop request is not being made, the data storage processing unit 51 determines whether or not the sent data matches the software change request command for the software currently being executed (step S303). When the transmitted data is recognized as a software change request command, a data transmission stop request is issued to the host computer 1 (step S3).
04).

If the data transmission stop request is being issued to the host computer 1, it is determined whether or not the stop request is due to a software change request (step S305). If the data sent is not a data transmission stop request and the transmitted data is not a software change request command, or if the data transmission stop request is being made but the stop request is not due to a software change request, the It is determined whether the data is an immediate processing command (step S306), and if the data is an immediate processing command, immediate processing is executed (step S30).
7). If it is not an immediate processing command, it is determined whether or not there is free space in the storage capacity of the input buffer (82) (step S308). (82) (step S309). If there is no free space in the input buffer (82), a data transmission stop request is issued to the host computer 1 (step S310).

On the other hand, if the data transmission stop request to the host computer 1 is due to a software change request, the data sent after the data transmission stop request is stored in the auxiliary buffer 83 (step S311). For this reason, the auxiliary buffer 83 issues a data transmission stop request to the host computer 1 and then transmits the data to the host computer 1.
Has at least a capacity to store the data to be sent until the request is recognized and the data transmission is actually interrupted. That is, in an interface such as a Centronics interface in which data transmission stop can be controlled by hardware, the response on the host computer 1 side is fast, but in the case of RS232C protocol control,
This is to deal with the delay in the response to the request.

The data stored in this manner is sequentially taken out of the input buffer 82 by the data processing unit 61 of the CPU 6 and interpreted.
Execute.

In this case, as shown in the flowchart of FIG.
First, the data processing section 61 determines whether or not there is data in the input buffer 82 (step S41). If the result of this determination is that there is data in the input buffer 82, the data is sequentially read from the input buffer 82 (step
S43). It is determined whether or not the read data is a software change request command (step S44). If the read data is not a software change request, a process based on each data is executed (step S45). When the read data is a software change request,
Transfer all control to requested software (step
S45). The destination software is the auxiliary buffer 8.
Initialize the system while protecting the 3 raw data,
The input buffer 82 is also initialized (step S46).
Thereafter, the data processing section 61 again determines whether or not there is data in the input buffer 82 (step S41), confirms that there is no data in the input buffer 82, and then shifts to an auxiliary buffer processing routine (step S47).
The data in 3 is transferred to the input buffer 82 and the same processing as the above processing is performed. Then, when the interpretation and execution of all the data are completed, the process ends (step S48).

The auxiliary buffer processing routine is performed according to the flowchart shown in FIG. When the data processing unit 61 recognizes the software change request command while reading and interpreting / executing the data in the input buffer 82, after initializing the system, it is determined whether or not there is data in the auxiliary buffer 83. A judgment is made (step S51). When there is data in the auxiliary buffer 83, the data is read from the auxiliary buffer 83 (step S52). It is determined whether or not the read data is immediate processing data (step S53).
If the data is immediate processing data, immediate processing is performed (step S54), and data is subsequently read from the auxiliary buffer 83. If the data read from the auxiliary buffer 83 is not immediate processing data, the data is stored in the input buffer (step S55). Then, the process ends after reading all the data in the auxiliary buffer 83. (Step S56). On the other hand, when there is no data in the auxiliary buffer 83, it is determined whether a data transmission stop request is being issued to the host computer 1 (step S57).
If the data transmission stop request is being issued, the host computer 1 is notified that data transmission is possible, and the process ends (step S58).

[Effect of the Invention] As described above, the present invention stores data sent after a software change request command is sent to a printer in an auxiliary buffer, recognizes the software change request command, and initializes the system. The data stored in the auxiliary buffer is saved when the input buffer is initialized and the input buffer is initialized.
Since the data to be processed can be separated by the change request command as a delimiter, the data loss caused by the immediate processing of the software data after the software change by the software before the software change is prevented. be able to.

Further, since it is only necessary to add an auxiliary buffer to the RAM of the printer control device and add a processing program for the auxiliary buffer, data loss can be avoided without breaking the entire structure of the conventional software program.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the configuration of a laser printer according to an embodiment of the present invention, FIG. 2 is a block diagram showing the relationship of each memory to the flow of data processing in the above embodiment, and FIG. 4 is a flowchart showing an operation when data is stored in the input buffer and the auxiliary buffer, FIG. 4 is a flowchart showing an operation when reading data from the input buffer, and FIG. 5 is a flowchart showing an operation when reading data from the auxiliary buffer. is there. DESCRIPTION OF SYMBOLS 1 ... Host computer, 2 ... Control part, 3 ... Engine, 5 ... Host interface, 51 ... Data storage processing part, 6 ... CPU, 61 ... Data processing part, 8 ... RA
M, 82: Input buffer, 83: Auxiliary buffer.

Claims (1)

(57) [Claims] 1. A printer control device which receives a continuous data string from a host computer via one host interface, temporarily stores the data string in an input buffer, and creates and prints an image from the stored data. A software change request including an auxiliary buffer for storing data sent from the host computer after a transmission stop request is made to the host computer until the host computer interrupts data transmission when a change request is issued; A printer control device that separates data to be processed by using as a delimiter.