JP2004090232A - Recorder and its control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electronic apparatus and a recorder in which a program can be updated easily and inexpensively without deteriorating the performance. <P>SOLUTION: The recorder comprises a means for controlling the recording operation employing a recording head, an unrewritable storage means prestored with a program being executed by the control means, a second storage means for storing the address table of the program, and a third storage means for storing a correction program being executed in place of the program. The recorder further comprises a forth storage means for storing the correction program and an address table conversion program, and a table conversion means for altering the address table by executing the address table conversion program wherein the table conversion means is executed and the correction program stored in the fourth control means is stored in the third storage means when the recorder is started and then the control means executes the correction program. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an electronic device such as a recording device that can be updated by downloading control data, a structure of the downloaded data, and a storage method.
[0002]
[Background technology]
2. Description of the Related Art A conventional electronic device such as a recording apparatus stores a program in a non-rewritable mask ROM and operates the recording apparatus by executing the program. In such a configuration, it is impossible to update the program in the recording apparatus alone, and the program is updated by replacing the mounted mask ROM.
[0003]
In a recent recording apparatus, a program for operating the recording apparatus is stored in a rewritable nonvolatile element, and the program is executed from the rewritable nonvolatile element (memory element). In such a recording apparatus, there are elements that can be rewritten in a predetermined memory size unit or a block unit.
[0004]
[Problems to be solved by the invention]
However, changing the mask ROM requires time and cost for creating the mask ROM. Further, even when a rewritable nonvolatile memory element is used, product cost increases in order to secure a memory capacity capable of storing all programs.
[0005]
Further, when executing a program stored in the rewritable nonvolatile memory, there is a delay in accessing the nonvolatile memory.
[0006]
The present invention has been made in view of the above problems, and an object of the present invention is to provide an inexpensive electronic device and a recording device that can easily update a program without deteriorating performance as compared with the related art. .
[0007]
[Means for Solving the Problems]
In order to solve the above-described problems, a recording apparatus of the present invention includes a control unit that controls a recording operation using a recording head, a non-rewritable storage unit in which a program executed by the control unit is stored in advance, What is claimed is: 1. A recording apparatus comprising: a second storage unit for storing an address table; and a third storage unit for storing a correction program to be executed instead of a program, wherein the fourth storage stores a correction program and an address table conversion program. Means, table conversion means for changing the address table by executing the address table conversion program, execution of the table conversion means at the time of starting the recording apparatus, and correction program stored in the fourth storage means to the third storage means. After performing the storage, the control unit executes the correction program.
[0008]
Further, the control method of the recording apparatus of the present invention includes a control unit for controlling a recording operation using a recording head, a non-rewritable storage unit in which a program executed by the control unit is stored in advance, and an address of the program. A record comprising: a second storage unit for storing a table; a third storage unit for storing a correction program executed in place of the program; and a fourth storage unit for storing the correction program and the address table conversion program. A method for controlling an apparatus, comprising: a table conversion step of changing the address table by executing the address table conversion program; and a storing step of a correction program stored in the fourth storage unit in the third storage unit. And a control step of executing the table conversion step and the storage step at the time of starting the recording device. A.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
[0010]
[Example]
FIG. 1 shows an electronic apparatus, for example, an ink jet recording apparatus (printer). The CPU 101 prepares image data of a printer, drives a motor for recording control, controls ejection of a recording head (print head), analyzes commands transferred from a higher-level device (host device), various settings by input from the panel 112, and the like. I do.
[0011]
In this embodiment, in addition to this, analysis of program data at the time of program update, writing to the flash ROM 110, and at the time of system startup, a program read from the 110 flash ROM is written to the correction RAM 111, and then stored in the RAM 103. Update the address table for functions and global variables that exist.
[0012]
The ROM 102 stores a control program for driving the printer, various fixed value data (such as a motor drive table), font data, and the like. The program in the ROM 102 is read and executed by the CPU 101. Various fixed value data are used as initial values as they are, and are developed in the RAM 103 and processed and used by the CPU. In this embodiment, a non-rewritable mask ROM is used as the ROM, and the ROM operates as read-only.
[0013]
A function table for executing the function (referred to as function table A for the sake of explanation) is stored (developed) in the RAM 103 at the time of startup, and its address value is used for calling the function. (A function corresponding to each address can be used by referring to this address value.) The addresses of the global variables are similarly tabulated, and the addresses are called by the RAM 103 at the time of startup, and the addresses in the table are used. Is accessed.
[0014]
In the case of image data, the RAM 103 expands the image data read by the CPU 101 on the RAM 103 corresponding to the designated recording position (print position) and uses the image data as image data (print data). Further, the RAM 103 is also used as a work memory required for executing the program, and as a reception buffer as a temporary storage location for input data from the interface (I / F) 104.
[0015]
Further, in this embodiment, as described above, the table stores the addresses of the functions and the global variables. Further, it is also used for temporarily storing data in the download mode.
[0016]
The I / F 104 is connected to a host device (not shown) and receives data such as image data (print data), a print instruction command, and download program data.
[0017]
The I / F 104 according to the present embodiment has electrical specifications based on the USB standard, and transfers not only data from the host device but also the status of the printer to the host, thereby enabling bidirectional communication. I have.
[0018]
The EEPROM 105 not only stores the settings of the printer, but also stores the number of records (prints), the remaining amount of ink, and the like. The status of the printer is stored as corresponding paper, function items such as automatic power ON / OFF, and the like.
[0019]
In the printer of this embodiment, the motor controller 106 is used for printing by scanning the print head in the main scanning direction, and for printing by scanning the print head once or a plurality of times. The control of the motor controller 106 is performed by the CPU 101, and recording (printing) is performed using the constant speed region and the acceleration / deceleration region of the motor. Another control of the motor controller 106 is a transport motor controller (line feed motor controller) which is a transport motor (LF motor) for moving a recording medium (for example, recording paper) in the transport direction.
[0020]
This motor can operate independently of a carriage motor (a printhead scanning motor) that scans the printhead. In a normal printing operation, the printhead scanning motor scans once or a plurality of times and then a line feed motor. The controller controls the recording paper to be conveyed by a predetermined amount.
[0021]
FIG. 8 is a perspective view of the printer. A recording head 205 is mounted on a carriage 204 and is capable of reciprocating in a longitudinal direction along a shaft 203. The ink ejected from the recording head reaches the recording material 202 whose recording surface is regulated by the platen 201 at a minute interval from the recording head, and forms an image thereon.
[0022]
An ejection signal is supplied to the print head via the flexible cable 219 in accordance with image data. Reference numeral 214 denotes a carriage motor for scanning the carriage 204 along the shaft 203. A wire 213 transmits the driving force of the motor 214 to the carriage 204. A conveyance motor 218 is coupled to the platen roller 201 to convey the recording material 202.
[0023]
The resolution of the recording head is 600 DPI. This recording head has an ink jet system in which 320 recording elements for black and 128 recording elements for color are arranged. The recording element includes a driving unit and a nozzle, and the driving unit can apply heat to the ink by a heater. The ink causes the film to boil due to the heat, and the pressure change caused by the growth or shrinkage of the bubble due to the film boiling causes the ink to be ejected from the nozzle.
[0024]
Returning to the description of FIG. 1, the bus line 109 is a data and address bus for transferring data. The CPU 101 controls each unit from 102 to 111 using the 109 bus lines.
[0025]
A flash ROM 110 is an inexpensive memory having a serial input / output of data and a memory capacity of 16 Kbytes. In order to execute another program instead of the program stored in the ROM 102, a substitute program is stored in the flash ROM 110.
[0026]
The writing and reading of the flash ROM 110 are performed by the CPU 101. The writing is performed when the printing apparatus is in the download mode, and the reading is performed when the program is started (for example, when the power of the printer is turned on), the contents of the flash ROM 110 are checked by the CPU 101, and a predetermined keyword is stored. Is In this embodiment, this keyword is “BJPR”.
[0027]
Reference numeral 111 denotes a correction RAM. The correction RAM 111 is used to prepare a program that can replace the program stored in the ROM 102 together with the flash ROM 110. The usage is performed by writing a program read from the flash ROM 110 into the correction RAM 111 and executing the program. The correction RAM 111 is an SRAM that can be accessed at high speed so that the stored program can be executed at a high speed.
[0028]
When writing the program stored in the flash ROM 110 into the correction RAM 111, only the program is written into the correction RAM 111 without reading out the keyword. At the same time, a table conversion program is also written in the correction RAM 111.
[0029]
Thereafter, by executing the table conversion program, the addresses stored in a part of the function table A store the addresses of the corrected RAM 111 after conversion.
[0030]
With this operation, the function stored in the ROM 102 is now called from the function previously stored in the ROM 102.
[0031]
In the allocation of the memory space in this embodiment, for example, 0x0000 to 0x5FFFF is allocated to the ROM 102, and 0x60000 and thereafter are allocated to the correction RAM 111.
[0032]
2 and 7, a description will be given of processing when downloading a program in the present embodiment.
[0033]
In FIG. 7, the shift to the download mode is performed by pressing all of the power key, the reset key, and the door key when the power of the printer is turned on. If all the keys have been pressed (S31), the mode shifts to the download mode, and the USB interface enters a reception waiting state (S32). If the download data is received, a download process is performed (S33). If the reception is started, it is determined whether or not data is received at a predetermined time (S34), and if there is no data within the predetermined time, the operation returns to the normal state (ends). In this embodiment, 20 seconds is set as the time until data reception is completed.
[0034]
In FIG. 2, in the download mode, header analysis is performed in a state of receiving program data (S11). The received data is analyzed to determine whether or not the data transmitted from the header information is download data.
[0035]
In the case of download data, the process proceeds to S12, where the length data added to the header information is read, and all remaining data is received based on the length. The processing time is counted until the reception is completed.
[0036]
When all the data for the length is received, the SUM value added to the header information is compared with the SUM value of the actually received data, and it is checked whether the data is properly received (S13). If the SUM value is the same in the header information and the transferred data, the flow advances to S14 to erase (delete) the contents of the flash ROM used for writing. Either the entire erasure or partial erasure of the flash ROM can be selected depending on the conditions to be used. However, in this embodiment, the entire erasure is performed because the entire capacity is as small as 16 Kbytes.
[0037]
Next, the program data whose SUM value check is completed is stored in the flash ROM (S15). In this case, the header is removed and stored at the specified address. After that, the capacity (the number of data) of the written program and a keyword (storage completion information) indicating that the writing has been completed are stored in the determined address (S16), and the processing is terminated to reset the system.
[0038]
FIG. 3 shows the printer startup processing after downloading the program as shown in FIG. At the time of this startup, the data at the keyword storage address of the flash ROM is read, and it is determined whether or not a keyword (information) indicating completion of writing (storage completion) is stored (S21). If the designated keyword is stored, the process proceeds to S22, where the program capacity (data length) stored in the flash ROM is read, and then the program is loaded based on the program capacity (program size). Read from the flash ROM (S23). After that, the read program is written to the correction RAM (S24).
[0039]
Thereafter, a program for updating the address table of functions and global variables in the program written in the correction RAM is started (S25). By these processes, the function on the correction RAM can be used instead of the function stored in the ROM 102 which has been used conventionally.
[0040]
FIG. 4 illustrates how the program is actually changed.
Reference numeral 401 denotes a non-rewritable ROM space. When the function Func1 calls the function funcA, the function 402 refers to the table “func [] []” 402, finds the function funcA that is the first element of the table, and refers to the address to call the function. This method can be similarly applied to global variables by referring not only to functions but also to tables of variables.
[0041]
The operation up to this point is the operation of the program before the change (stored in the ROM 102). If the program needs to be changed, prepare a program to be downloaded as follows.
[0042]
First, a function of the same type as the function to be changed in the program is defined. After correcting the contents of the function, the address specification is changed so that the function can be executed in the correction RAM, and compilation and linking are performed.
[0043]
Next, in order to modify the function and replace the address of the function to be modified with the address of the substitute function for modification (change the address of the function to be modified to the address of the substitute function), the address of that function Create a program like 403 with the conversion program, compile and link.
[0044]
By executing such a program, the first element of func [] [] stored in the RAM 103 is changed from the address of funcA to the address of funcB. This allows funcB to be called, and funcB is executed instead of funcA.
[0045]
The function in the non-rewritable ROM 102 refers to the address of the first element from the address table called func [] [] as before the correction. However, since the address has been changed in 403, this time, instead of referring to the address of funcA, it refers to the address of funcB and calls that funcB. Since funcB is a corrected program, the whole program operates in a corrected form.
[0046]
As described above, the program can be modified using one function or one global variable as a modification unit, and the program can be modified with a smaller memory capacity than before.
[0047]
FIG. 5 shows the structure of data transferred from the host device. In this embodiment, the download data to be used is identified in the header section 501. The contents of the header are "0x1B, 0x00, 0x18, 0x00".
[0048]
0x1B, which is the first data, is recognized as an escape sequence and is recognized as a data delimiter or head. Subsequent 3-byte data is a recognition code, which is a code meaning download data. Reference numeral 502 denotes sum value data, which is represented by 16 bits. This value is the sum value of the program data 504. Reference numeral 503 stores the capacity (length of data) of the entire program data in 16 bits. Reference numeral 504 denotes data actually stored in the flash ROM, which has a binary data format, and all areas not used in the correction RAM 111 are filled with 0xFF.
[0049]
FIG. 6 is a map of the flash ROM and the correction RAM. At the beginning of the address, a keyword indicating the end of writing is stored in a 4-byte area. Thereafter, the capacity (length) of the program is stored in an area of 2 bytes. This capacity is the length from the address conversion program starting at address 0x10 to the last address of the changing function program stored at address 0x400 and thereafter.
[0050]
The data value 0xFF is embedded from the address next to the last address of the address conversion program to just before the head of the change function program (address 0x3FF), and this area is also included in the program capacity.
[0051]
Thereafter, as described above, the address conversion program is stored from address 0x10, and the function program for change is stored from address 0x400. This map has exactly the same configuration as the map of the flash ROM and the correction RAM, and is all copied when the power of the recording apparatus is turned on. Thereafter, by executing the address conversion program, the function program for change becomes effective, and the program is modified.
[0052]
[Other Examples]
In the above embodiment, the checksum is used to detect a transmission error when transferring the program data for change, but a data communication error detection function such as CRC-16 may be used.
[0053]
Further, in the configuration of the change program data, the address conversion program and the change function program are divided into two areas when stored in the memory, but they are arranged at adjacent addresses when the change program is created. Thus, an unused area generated between the address conversion program and the change function program can be eliminated.
[0054]
Further, in the structure of the change program data, the image data of the change program has a binary data structure as a data structure. However, the image data of the change program has a data structure used for ROMization such as Intel HEX or Motorola S format. However, since the data check mechanism can be used in units of 16 bytes, the reliability is further improved.
[0055]
【The invention's effect】
As described above, according to the present invention, a program in place of a program stored in a non-rewritable ROM can be modified at low cost.
[0056]
In particular, since the program can be modified for each function or for each variable as the minimum unit for modifying the program, the program can be modified with a small memory capacity.
[0057]
In addition, the execution speed of this alternative program can be faster than executing the program stored in the flash ROM.
[Brief description of the drawings]
FIG. 1 is a block diagram of a printer according to an embodiment. FIG. 2 is a control flow of a writing process to a flash ROM according to the embodiment. FIG. 3 is a control flow at the time of starting up the printer according to the embodiment. Description of the part [FIG. 5] Transfer data structure of the embodiment [FIG. 6] Data arrangement diagram of flash ROM of the embodiment [FIG. 7] Control flow of download processing of the embodiment [FIG. 8] Perspective view of printer in the embodiment

Claims (7)

Control means for controlling a printing operation using a printhead, non-rewritable storage means in which a program executed by the control means is stored in advance, second storage means for storing an address table of the program, and the program A storage device for storing a correction program to be executed in place of the storage device,
Fourth storage means for storing the correction program and the address table conversion program;
Table conversion means for changing the address table by executing the address table conversion program,
At the time of starting the recording device, after executing the table conversion unit and storing the correction program stored in the fourth storage unit in the third storage unit, the control unit executes the correction program. A recording device characterized by the above-mentioned. 2. The recording apparatus according to claim 1, wherein the recording apparatus further includes a program storage unit that stores the correction program and the address table conversion program in the fourth storage unit. 3. The recording apparatus according to claim 2, wherein the program storage unit stores storage completion information in the fourth storage unit when the storage processing is completed. 3. The program storage unit according to claim 2, wherein the program storage unit includes: a data analysis unit that analyzes whether the data is data to be stored; and a communication error detection unit that detects an error at the time of input by the input unit. Recording device. 4. The recording apparatus according to claim 3, wherein the storage completion information is stored at a head address of the fourth storage unit. The recording apparatus according to claim 1, wherein the correction program is in a binary format. Control means for controlling a printing operation using a printhead, non-rewritable storage means in which a program executed by the control means is stored in advance, second storage means for storing an address table of the program, and the program A control method for a recording apparatus, comprising: a third storage unit that stores a correction program to be executed instead of the storage unit; and a fourth storage unit that stores the correction program and the address table conversion program.
A table conversion step of changing the address table by executing the address table conversion program,
Storing the correction program stored in the fourth storage means in the third storage means;
A control method for a printing apparatus, comprising: a control step of executing the table conversion step and the storing step when the printing apparatus is started.

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