JPH03166620A - Printer controller - Google Patents

Abstract

PURPOSE:To prevent the data loss by saving the data stored in an auxiliary buffer at the time of recognizing a software change request command and initializing a system, and also, initializing an input buffer. CONSTITUTION:Data which is sent after a software change request command is sent to a printer is stored in an auxiliary buffer 83, and at the time of recognizing the software change request command and initializing a system, and also, initializing an input buffer 82, the data stored in the auxiliary buffer 83 is saved. In such a way, a data loss at the time of software change can be eliminated without adding a buffer to a host side.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a printer control device such as a laser printer, and particularly to prevention of data loss after a software change request.

[Prior Art] In order to cover the computer network, which was conventionally supported by a number of different types of printers, with as few printers as possible, it is intended to change the commands of different types of printers by a method called software change. ing. Conventional printer control devices do not have the ability to change software using commands communicated with a host computer, and software changes are made using a control panel attached to the printer itself. In addition, in recent years, software changes have been made using communication commands5, but in this case too, it was only possible to create a long period of time or a single document using only the specified software. However, in current document creation, a single document is created using different types of processing software within a printer control device, and various applications are used using a single printer connected on a network. It is hoped that this will be possible. In this case, data strings for different types of software are continuously sent to the laser printer, etc. via the host interface, with software change commands as delimiters. The input buffer control of laser printers and other devices to which such data strings are sent is based on command data that immediately interprets and executes the data received from the host computer, such as system reset commands and status request commands, etc., depending on the software. Other data that follows. Separate into text data for printing, image data, etc. Command data is immediately interpreted and executed, and data other than 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. Also, soft air
Change request commands are usually not interpreted immediately, but are stored in the input buffer. This is because the data entered into the input buffer before the software change request command is an example of data for a different type of software before the software change, and should be processed in the software change 111I. Therefore, the software change request command is also stored in the input buffer in the same way as normal data. When the software change request command is recognized while executing the data stored in this input buffer while sequentially reading and interpreting the data stored in the input buffer, the software jumps to the specified software initialization routine and changes are made. The entire control is entrusted to the developed software. After the new software initializes the system, it starts communicating with the host computer and prints. [Problem to be Solved by the Invention] In the input buffer control of a laser printer, etc., the software stored in the input buffer
When initializing the system by recognizing a change request command, the input buffer is also initialized. As a result, the data stored in the input buffer by the pre-conversion software after the software change request command was also erased, resulting in data loss. In order to resolve this problem, a buffer is provided on the host computer side, a delay time is set for data transmission immediately after the software change request command is exited, and data communication is resumed after the software change of the printer control device is completed. Some methods have been adopted to do so. However, with the method of providing a buffer on the host side, it is necessary to add a means to recognize the software change request command of the printer being used and a means to control the waiting time at the time of software change to the host side. System construction becomes troublesome. In addition, there are many cases in which the host cannot take the above measures, making it difficult to completely eliminate data loss problems. Therefore, it is necessary to take measures against data loss in the printer during software changes, but conventionally it has not been possible to take measures within the printer. The reason for this is that ■ Immediate processing commands etc. are not stored in the input buffer, but software change request commands are stored in the input buffer, and ■ Software change request commands are stored in the input buffer.
This is because the input buffer is also initialized when the system is initialized immediately after the change. The inconvenience caused by the latter reason can be solved by limiting the input buffer area for each different software in advance so that it can be used as is even after a software change. However, the inconvenience caused by the former reason cannot be solved simply. That is, until the routine that sequentially reads and controls data stored in the input buffer recognizes the software change request command, the immediate processing command is executed by the software before the software change is executed. Therefore, if the data sent after receiving the software change request command is data that should not be immediately processed by the software after the software change and is for normal processing, this data will be processed before the software change. There is a possibility that the data will be processed immediately by the software, resulting in data loss. The most obvious example is when there is an image data transfer after a software change request command. Since any data code is predicted for image data, the image data transfer command is processed in the same manner as the immediate processing command, and only the image data that follows is not immediately processed. It would be good if the immediate processing commands and image data transfer commands could be unified in each software, but this is not possible with software used as emulations of existing printers. Therefore, if the recognition of whether or not it is image data differs between the software before and after the software change, the image data for the software after the software change will be immediately processed by the software before the software change, and the resulting This may result in data loss. In order to eliminate this data loss, it is possible to store immediate processing commands in the input buffer or to have input buffer control processing routines for each piece of software, but this has the disadvantage of making the program huge. This invention has been made to solve these shortcomings, and aims to provide a printer control device that can eliminate data loss during software changes without adding a buffer to the host side. It is something. [Means for Solving the Problems] The printer control device according to the present invention is capable of controlling data transmission from when a request for a software change is made to a host computer to stop sending data until the host computer actually stops sending data. It is characterized by having an auxiliary buffer for storing data sent from the host computer between the two. [Operation] In this invention, data sent after a software change request command is sent to the printer is stored in an auxiliary buffer, the system is initialized by recognizing the software change request command, and the input buffer is initialized. Sometimes the data stored in the auxiliary buffer is saved.

[Embodiment] FIG. 1 is a block diagram showing the configuration of a laser printer according to an embodiment of the present invention. In the figure, 1 is a host computer that sends out character information and image information, 2 is a control unit of a laser printer, 3 is an engine that prints image information generated by control unit 2 onto paper, and 4 is a computer that is recorded on a font card, etc. This is an external information input section for inputting external information.

The control unit 2 includes a host interface 5. CPU6. Program ROM7. RAM8. Font RAM9. Non-volatile RAMIO, scaling processing unit 11. It has an operation panel 12, an interface 13, a video control section 14, and an engine control section 15, which are connected to each other by a CPU bus 16. Further, the video control unit 14 and the engine control unit 15 are connected to the engine 3 via a laser printer video interface (hereinafter referred to as LPVI) 17. The host interface 5 is an interface for connecting between the host computer l and the control unit 2, and
S232C. Compliant with Centronics specifications, etc. The CPU 6 is a 16-bit or 36-bit central processing unit that has a data processing section 6l and an image information processing section 62, and controls the entire control section 2 in an integrated manner. The program ROM 7 stores microcode for controlling the CPU 6. RAM8 is a large capacity random access memory, and system memory 81. Input buffer 82 consisting of a ring buffer. Auxiliary buffer 83
and page buffer 84. Font file 85. Microfile 86. Image file 87. Used for print control file 88, video buffer 89, etc. The font ROM 9 stores font data for converting character information sent from the host computer 1 via the host interface 3 into image information. The nonvolatile RAM 10 stores information for controlling the operating state of the printer after the power is turned on.

The scaling processing unit 11 performs scaling processing of image information. The video control unit 14 serially 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, and
7 to engine 3. The engine control unit 15 detects the state of the engine 3 via a bidirectional serial signal via the LP VI17, and controls the engine 3 by sending commands. First, an overview of the operation of the laser printer configured as described above will be explained with reference to the block diagram shown in FIG. 2 showing the relationship of each memory to the flow of data processing. Data sent from the host computer 1 is stored directly or temporarily in the auxiliary buffer 83 via the data storage processing section 5l of the host interface 5, and then stored in the input buffer 82. This imbut 1.
The data stored in the buffer 82 is taken out by the data processing unit 6l of the CPU 6, and is sent to the RA according to the type of data.
It is registered in the memory area of M8. In other words, specifying the paper transport path. Print sequence system such as specifying the number of prints {Wholesale information is registered in the print control file 88, page layout information such as the relationship between print data and print position is stored in the page buffer 84, image information is stored in the image file 87, and downloaded fonts are stored in the font File 85 contains overlay information, etc., and microfile 86
are registered respectively. The image information processing unit 62 of the CPU 6 uses a page buffer 78
Image file 87 according to the contents of 4. The contents of the font file 85 and font ROM 9 are read and expanded into the video buffer 89. This video buffer 8
When one page's worth of print data is developed in 9, the engine control unit 15 starts 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 developed in the video buffer 89 is stored in the video control units l2 and L.
The video data is sent to the engine 3 via the PVI 17, and the sent video data is printed on printing paper by the engine 3. Next, in the above processing operation, 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 783 are explained in the flowcharts of FIGS. 3 to 5. This will be explained with reference to. When storing data in the data storage processing section 5l, the third
As shown in the figure, when data is sent from the host computer l to the control unit 2, the data storage processing unit 5l of the host interface 5 is activated (step S301).
For each data transmission, the printer control unit 2 also determines whether the host computer 1 is requesting to stop data transmission (step S302). The data storage processing unit 5l determines whether the command matches the software change request command for the software being executed (step S303). When recognizing that the sent data is a software change request command, it issues a data transmission stop request to the host computer l (step S304).

Also, if a data transmission stop request is being made to the host computer, the stop request is
It is determined whether the request is due to a change request (step S305). Then, if the data sent is not a request to stop data transmission and the sent data is not a software change request command, or if the data transmission stop request is in progress but the stop request is not due to a software change request, the sent data is Determine whether or not it is an immediate processing command (Step 7" S306). If it is an immediate processing command, execute immediate processing (step S307). Also, if it is not an immediate processing command, check whether there is free space in the storage capacity of the input buffer (82). It is determined whether or not (step 3308), and if there is free space in the storage capacity of the input buffer (82), the sent data is stored in the input buffer (82) (step S309). If not, issue a data transmission stop request to host computer l (step S310). On the other hand, if the data transmission stop request to host computer l is due to a software change request, the data sent after the data transmission stop request is sent to the auxiliary buffer. 83 (step S311).For this reason, the auxiliary buffer 83 requests the host computer 1 to stop data transmission until the host computer 1 recognizes the request and actually interrupts data transmission. It has a minimum capacity to store the data to be sent.In other words, in interfaces such as the Centronics interface that can control data transmission stop using hardware, the response from the host computer side is fast, but the IIS232G protocol control In this case, there is a delay in the response to the request, so this is to deal with this.The data processing unit 6l of the CPU sequentially retrieves the data stored in this way from the input buffer 82, interprets and executes it. As shown in the flowchart of FIG. 4, the data processing unit 6l first determines whether or not there is data in the input buffer 82 (step S41).As a result of this determination, if there is data in the input buffer 82, , sequentially reads data from the input buffer 82 (
Step S43). It is determined whether this read data is a software change request command (step S
44), When it is not a software change request,
Processing is performed using each data (step S45). If the read data is a software change request, all control is transferred to the requested software (step S45). The destination software then initializes the system while protecting the unprocessed data in the auxiliary buffer 83, and also initializes the input buffer 82 (step 346). Thereafter, the data processing unit 6l again determines the presence or absence of data in the input buffer 82 (step S41), and after confirming that there is no data in the input buffer 82, moves to the auxiliary buffer processing routine (step S47). The data is transferred to the input buffer 82 and the same processing as described above is performed. Then, when all the data has been interpreted and executed, the process ends (step S48). The above-mentioned auxiliary buffer processing routine is carried out according to the flowchart shown in FIG. When the data processing unit 6l reads, interprets, and executes the data in the input buffer 82,
When the software change request command is recognized, after initializing the system, it is determined whether there is data in the auxiliary buffer 83 (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 the read data is immediate processing data (step S5).
3) If the data is immediate processing data, immediate processing is performed (step S54). Thereafter, data is read out from the auxiliary buffer 83. Further, when the data read from the auxiliary buffer 83 is not immediate processing data, the data is stored in the input buffer (step S55).
). After all the data in the auxiliary buffer 83 is read out, the process ends. (Step 356). On the other hand, if there is no data in the auxiliary buffer 83, it is determined whether the host computer 1 is being requested to stop data transmission (step S57). If a data transmission stop request is in progress, the process is terminated by notifying the host computer that data transmission is possible (step 358). The data sent after being sent to the auxiliary buffer is stored in the auxiliary buffer, and when the software change request command is recognized, the system is initialized, and the input buffer is also initialized, the data stored in the auxiliary buffer is saved. Therefore, the data to be processed can be separated using the software change request command as a delimiter, so data loss that occurs when the software before the software change immediately processes data for the software after the software change can be avoided. It can be prevented. Furthermore, since it is only necessary to add an auxiliary buffer to the RAM of the printer control device and add a processing program for this auxiliary buffer, data loss can be avoided without destroying the overall structure of the conventional software program.

[Brief explanation of the drawing]

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 data processing flow of the above embodiment, and FIG. 3 is a block diagram showing the relationship of each memory to the data processing flow of the above embodiment. 4 is a flowchart showing the operation when data is stored in the input buffer and the auxiliary buffer, FIG. 4 is a flowchart showing the operation when reading data from the input buffer, and FIG. 5 is a flowchart showing the operation when reading data from the auxiliary buffer. It is. l...Host computer, 2...Control unit, 3
...Engine, 5...Host interface, 5l...Data storage processing unit, 6...CPU,
6l...Data processing unit, 8...RAM, 82...
...Input buffer, 83...Auxiliary buffer.

Claims (1)

[Claims] In a printer device that receives data from a host computer via a host interface, temporarily stores it in an input buffer, and creates and prints an image from the stored data, when a software change request is received, the host computer 1. A printer control device comprising: an auxiliary buffer for storing data sent from a host computer after a transmission stop request is made until the host computer interrupts data transmission.