JP2006065550A - Nonvolatile memory writing control method for ink jet recording apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To equalize writing frequencies to a nonvolatile memory. <P>SOLUTION: A nonvolatile memory writing control method includes address replacement information and address count information in the nonvolatile memory. When the difference between the maximum value and minimum value for writing frequencies indicated by the address count information becomes a specified value or more, the contents of an address indicating the maximum value and minimum value are replaced, and are written in the nonvolatile memory. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an inkjet recording apparatus, and more particularly to a writing control method for a nonvolatile memory.

2. Description of the Related Art Conventionally, an ink jet recording apparatus is equipped with a non-volatile memory (EEPROM) for storing printer information. In the nonvolatile memory, there is a limit of data writing to the memory area of the same cell (same address), and is usually about 10,000 to 100,000 times. Therefore, the nonvolatile memory chip is selected and mounted on the ink jet printer so as not to exceed the limit of the number of times of writing data with reference to the number of times of writing to the address having the highest writing frequency.
JP 2000-094763 A JP 2002-120375 A

  However, in the above conventional example, the non-volatile memory chip is selected based on the address with the highest write frequency, so the address with the low write frequency is over-spec, and the original performance of the non-volatile memory can be extracted. I was not there. Also, if the number of data writes to the memory area with the same address is extremely large, an expensive nonvolatile memory chip must be selected accordingly, and a method for randomizing the write address has also been proposed. However, there was a problem that the nonvolatile memory could not be controlled accurately in conjunction with the number of times of writing.

  The present invention has been made paying attention to the above points, and an object of the present invention is to provide a nonvolatile memory writing control method for an ink jet recording apparatus that equalizes the writing frequency with respect to the nonvolatile memory.

  In order to solve the above problems, the present invention is a write control method for leveling the write frequency for a non-volatile memory having a limited number of data writes to the memory area of the same address. The address replacement information and address count information are stored in the memory. When the difference between the maximum and minimum write counts indicated by the address count information is greater than or equal to the “specified value”, the contents of the address indicating the maximum and minimum values are displayed. It is characterized by providing an ink jet recording apparatus which can be mounted even on an inexpensive non-volatile memory chip by controlling so that the same address is not specially written and the number of times of writing is increased by writing by replacement.

  Furthermore, if this is summarized, it can be summarized in the following configuration.

  (1) In a control method for writing data to a nonvolatile memory with a limited number of times of writing, an address indication storage area for instructing the contents to be stored in the nonvolatile memory, an address indication means, and the nonvolatile memory When the difference between the maximum value and the minimum value of the address count information exceeds a specified value, the address count information is indicated by the address indication means. A non-volatile memory writing control method for an ink jet recording apparatus, comprising: means for replacing an address indicated by the maximum value and the minimum value, and means for replacing data by the means for replacing the address.

  In the ink jet recording apparatus according to the present invention, the contents of the address having the maximum value and the address having the minimum value of the number of times of writing to the nonvolatile memory in which the number of times of data writing to the memory area of the same address is limited Thus, it is possible to provide an ink jet recording apparatus that can level the writing frequency, control the same address so that the number of writing does not increase, and can be mounted even on an inexpensive nonvolatile memory chip.

  Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to examples.

  As shown in FIG. 1, the recording apparatus incorporates a CPU 1 (central processing unit) such as a programmable microprocessor. The ROM 2 stores font data, a program instruction sequence executed by the CPU 1 for controlling the recording apparatus system, and various control tables. The RAM 22 is sent from the host computer 21 through the interface 20 to the print buffer in the RAM 22 for print output by the black recording head 11 and the color recording head 12 while the CPU 1 executes the program stored in the ROM 2. Stores various recorded data.

  The gate array 8 serving as control logic controls the print head driver 10 to output control signals for the nozzles in the print heads 11 and 12, and transfers data between the interface 20, the CPU 1, and the RAM 22. The control logic of the DC motor driver 13 and the pulse motor driver 16 is further provided.

  The recording apparatus includes a CPU 1 connected to the CPU bus 7 and an interface 20 that mediates between the recording apparatus and the host computer 21. The interface 20 has a signal path capable of bidirectional transmission and reception, and transmits and receives recording data and commands from the host computer 21.

  The DC motor driver 13 controls the two motors (line feed motor 14 and carriage motor 15). The line feed motor 14 drives the conveying roller to control sheet feeding and feeding / discharging. The carriage motor 15 drives the carriage to control the movement of the recording heads 11 and 12 to the recording position on the scanning line. The pulse motor driver 16 also controls the two motors (the paper feed motor 17 and the recovery motor 18). A sheet feeding motor 17 controls pickup in sheet feeding. The recovery motor 18 controls recovery operations such as cleaning, wiping, and cap of the recording heads 11 and 12. The black recording head 11 and the color recording head 12 controlled by the recording head driver 10 are detachable units that are moved by a carriage. These heads include ink ejection nozzles for forming a recording image on a recording medium, Also included is a head diode 9 that feeds back information regarding the presence and characteristics of the removable recording head.

  Based on the electrical signal sent from the recording head driver 10, the electrothermal conversion elements of the recording heads 11 and 12 are driven to generate thermal energy for causing film boiling in the ink. Since the ink ejection amount varies depending on the temperature of the recording heads 11 and 12, the temperature output from the thermistor 3 for measuring the ambient temperature in the recording apparatus and the head diode 9 of the recording heads 11 and 12 is monitored.

  The nonvolatile memory 19 includes a checksum 19a, an ink status 19b in the ink cartridge, an ink consumption history 19c, an error occurrence status history 19d, a head recovery history 19e, a recording head alignment parameter 19f, a user usage status history 19g, and a sensor correction value. 19h, motor drive history 19i, factory adjustment value 19j, CD-R printing position correction value 19k, printer state 19l, recording head initial state count 19m, destination information 19n, waste ink counter 19o, address replacement information 19r, This is a non-volatile memory for storing printer information such as address count information 19s. Buffer 1 22a, Buffer 2 22b, and Buffer 3 22c are buffers on the RAM 22 used for reading, writing, and comparing the contents of the nonvolatile memory.

  Various sensors 4 are mounted on the recording apparatus. The PE sensor 4a (paper end sensor) detects a passing sheet. The ASF sensor 4b (feed sensor) detects the rotational position of the cam of the feed unit. The PG sensor 4c (purge sensor) detects the cam position of the head recovery unit. The ink remaining detection sensor 4d is an optical sensor, and detects the presence or absence of ink in the ink tank by the light transmittance when the ink tank mounted on the carriage passes over the sensor by moving the carriage. In addition, sensors such as a cover sensor interlocked with the cover switch 5c, an encoder 4e for reading the position information of the carriage, and an encoder 4e for reading the position information of the LF are also included here. A switch 5 for user operation such as a power switch 5a and a resume switch 5b is provided. Further, a display LED 6 is provided for informing the user of the status of the recording apparatus. The timer 23 is involved in the control of each motor. Note that the power supply 24 supplies power for driving the recording apparatus.

  FIG. 2 is an original map of a non-volatile memory 19 of 1024 bytes that can be accessed in 16-bit units. The checksum 19a for error recovery of the non-volatile memory, the ink status 19b in the ink cartridge, the ink consumption history 19c, Error occurrence status history 19d, head recovery history 19e, recording head alignment parameter 19f, user printer usage status history 19g, sensor correction value 19h of various sensors 4, driving history 19i of motors 14, 15, 17, 18 and factory shipment Time adjustment value 19j, CD-R printing position correction value 19k, printer state 19l during capping and cleaning, recording head initial state count 19m for initial recovery operation of recording head, destination information 19n, and product life Waste ink counter 19o, non-volatile In order to store printer information such as a free area 19p of the volatile memory, a backup area 19q of the non-volatile memory, address replacement information 19r for generating a logical address, and address count information 19s for counting the number of physical address writes The contents of the non-volatile memory are shown.

  Each content is assigned the address indicated in FIG. In the backup area, the same data as the range of addresses 0 to 254 is stored. The address replacement information 19r is allocated to an invariant fixed area indicating a logical address of a data area in the range of addresses 0 to 254. For example, data “206” is stored in 19r2 for address 206, and 19r2 for address 206 in address replacement information 19r indicates 206 in the data area. Similarly, 19r3 for the address 208 in the address replacement information 19r indicates the 208 address of the data area. The address count information 19s stores the number of writes in the range of data area addresses 0 to 254. For example, data “10” is stored in the address 206 19s2 and represents the number of times of writing at the address 206 in the data area.

  The range of addresses 0 to 254 is an address replacement target area, and changing the address replacement information 19r means that the logical address in the range of data area addresses 0 to 254 is updated. The address count information 19s uniquely indicates the same address, and even if the address replacement information 19r changes, the address indicated by the address count information 19s does not change, and always represents only the write count of the indicated address.

  The change timing of the address replacement information 19r is only when the maximum value and the minimum value of the address count information 19s indicating the number of times of writing to the nonvolatile memory exceed the “specified value”, and is always written when writing to the nonvolatile memory. There is nothing. As the “specified value” related to the change of the address replacement information 19r, an appropriate value is obtained depending on the number of times the nonvolatile memory can be written. The address replacement target area in the data area is a replacement of an address with a high write count and an address with a low write count by switching the logical address indicating the maximum value and the minimum value of the address count information 19s indicating the write count of the nonvolatile memory. Thus, the frequency of writing to one address is drastically reduced, and the number of times of nonvolatile memory writing is leveled.

  In addition, this configuration is configured such that the range of addresses 0 to 510 in the data area including the backup area and the ranges of addresses 512 to 1022 of the address replacement information 19r and address count information 19s can be interchanged.

  FIG. 3 is a memory map after the logical address information of the nonvolatile memory 19 is changed. The data of 19r3 for the address 208 in the address replacement information 19r is “210” indicating the address 210 of the data area. Further, the data of the address 210 for 19r4 in the address replacement information 19r is “208”, which indicates the address 208 of the data area. That is, the sensor correction value 19h at the address 208 in the data area in FIG. 2 indicates the address 210 in FIG. 3 after the logical address change, and the motor drive history 19i at the address 210 in the data area in FIG. In FIG. 3, the address 208 is indicated.

  Similarly, the data of the address 214 19r6 in the address replacement information 19r is “218”, which indicates the address 218 of the data area. Further, the data of the address 218 19r8 in the address replacement information 19r is “214”, which indicates the 214th address of the data area. That is, the CD-R print position correction value 19k at the address 214 in the data area in FIG. 2 indicates the address 218 in FIG. 3 after the logical address change, and the print head initial state count 19m at the address 218 in the data area in FIG. In FIG. 3 after changing the logical address, the address 214 is shown.

  In FIG. 4, when a non-volatile memory writing event occurs due to power-off, recovery completion, etc., the non-volatile memory writing program of the inkjet recording apparatus stored in the ROM 2 (see FIG. 1) starts (S4-1). . Information to be written is instructed to the nonvolatile memory writing program. In S 4-2, the contents of the nonvolatile memory are read into Buffer 1 22 a of the RAM 22. In S4-3, the entire contents of the read Buffer 1 22a are copied to the Buffer 2 22b of the RAM 22. In S4-4, the position of the write data is obtained based on the instructed information to be written based on the address replacement information 19r in Buffer 1, and various data in Buffer 1 22a are updated. In S4-5, the address count information 19s of Buffer1 22a is updated. In S4-6, the data in the data area in Buffer1 22a is replaced based on the address count information 19s. In S4-7, the checksum of the entire Buffer1 22a is calculated, and the checksum 19a of the Buffer1 22a is updated. In S4-8, data comparison is performed based on the physical addresses of Buffer1 22a and Buffer2 22b. Only the different data of Buffer1 22a and Buffer2 22b compared in S4-9 is written to the nonvolatile memory, and the nonvolatile memory writing process is terminated in S4-10.

  In FIG. 5, the address replacement process program shown in S4-6 of FIG. 4 starts (S5-1). In S5-2, the Buffer3 22c is initialized, and all corresponding addresses described later are unprocessed. In S5-3, the maximum value of the address count information of Buffer1 22a of the RAM 22 read from the nonvolatile memory is found. In S5-4, it is checked in Buffer3 22c whether the address corresponding to the maximum value of the found address count has been processed. If it has already been processed, the process returns to S5-3 to search for address count information having the next largest value. When not yet processed, the minimum value of the address count information of Buffer1 22a of the RAM 22 read from the nonvolatile memory is found in S5-5. In S5-6, it is checked in Buffer3 22c whether or not the address corresponding to the minimum value of the found address count has been processed. If already processed, the process returns to S5-5 to search for address count information having the next smallest value. When not yet processed, it is checked in S5-7 whether the difference between the maximum value and the minimum value of the address count is equal to or greater than the “specified value”. If it is not equal to or greater than the “specified value”, the process proceeds to S5-11, and the process ends. If it is equal to or greater than the “specified value”, the address replacement information indicated by the maximum value and the minimum value of the unprocessed address count of Buffer1 22a is exchanged in S5-8. Similarly, in S5-9, the data indicated by the maximum value and the minimum value of the unprocessed address count of Buffer1 22a is exchanged. In S5-10, the corresponding address in Buffer3 22c is processed, and the process returns to S5-3.

It is a control block diagram of an inkjet recording device. It is a detailed map of the non-volatile memory of an inkjet recording device. 4 is a memory map after replacement of a logical address of a nonvolatile memory of an inkjet recording apparatus. It is a flowchart of writing of the non-volatile memory of an inkjet recording device. It is a flowchart of the address replacement process of the non-volatile memory of an inkjet recording device.

Explanation of symbols

1 CPU
2 ROM
3 Thermistor 4 Sensor 4a PE sensor 4b ASF sensor 4c PG sensor 4d Residual ink detection sensor 4e CR, LF encoder 5 Switch 5a PowerSW
5b ResumeSW
5c CoverSW
6 LED
7 CPU bus 8 Gate array 9 Head diode 10 Recording head driver 11 Black recording head 12 Color recording head 13 DC motor driver 14 Line feed motor 15 Carriage motor 16 Pulse motor driver 17 Paper feed motor 18 Recovery motor 19 Non-volatile memory 19a Checksum 19b Ink status in ink cartridge 19c Ink consumption history 19d Error occurrence history 19e Head recovery history 19f Recording head alignment parameter 19g User usage history 19h Sensor correction value 19i Motor drive history 19j Factory adjustment value 19k CD- R printing position correction value 19l Printer state 19m Recording head initial state count 19n Destination information 19o Waste ink counter 19p Empty area 19q Backup area 19r address replacement information 19s address count information 20 interface 21 the host computer 22 RAM
22a Buffer 1
22b Buffer2
22c Buffer3
23 Timer 24 Power supply

Claims (7)

  In a control method for writing data to a nonvolatile memory with a limited number of times of writing, an address indication storage area for instructing contents to be stored in the nonvolatile memory, an address indication means, and the number of times of writing to the nonvolatile memory Address count information storage area and address count information means, and when the difference between the maximum value and the minimum value of the address count information exceeds a specified value, the address count information is indicated by the address indication means. A nonvolatile memory writing control method for an ink jet recording apparatus, comprising: means for replacing an address indicated by a value and a minimum value; and means for replacing data by the means for replacing the address.   The nonvolatile memory writing control method for an ink jet recording apparatus according to claim 1, wherein the entire address indication storage area and the entire address count information storage area stored in the nonvolatile memory are replaced.   2. The nonvolatile memory writing of an ink jet recording apparatus according to claim 1, wherein the entire address control area and the entire data area of the address indication storage area and the address count information storage area stored in the nonvolatile memory are replaced. Control method.   3. The nonvolatile memory write control for an ink jet recording apparatus according to claim 2, wherein a timing for replacing the entire address indication storage area and the entire address count information storage area stored in the nonvolatile memory is obtained from a timer. Method.   4. The inkjet according to claim 3, wherein a timing for replacing the entire address control area and the entire data area of the address indication storage area and the address count information storage area stored in the nonvolatile memory is obtained from a timer. A non-volatile memory writing control method for a recording apparatus.   2. The non-volatile memory writing control method for an ink jet recording apparatus according to claim 1, wherein the address indicating means stored in the non-volatile memory can indicate all addresses of the data area in the non-volatile memory.   2. The non-volatile memory writing control method for an ink jet recording apparatus according to claim 1, wherein the address count information means stored in the non-volatile memory can indicate all addresses of the data area in the non-volatile memory.

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