JP2012022541A - Electronic apparatus and program start control method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a program start control method and an electronic apparatus, capable of improving its reliability if the program is read from a nonvolatile memory and then the electronic apparatus starts.SOLUTION: An electronic apparatus includes a display part 12, an operating section 13, and a plurality of NAND flash memories 102 and 103 in which the same start program for start is stored, if data error on a first start program read from the memory 102 is detected(S203;Y), a second start program is read from the memory 103(S204), a selection message about whether or not the first start program is rewritten on the second start program is displayed on the display part 12(S205), and if the rewriting is selected by the operating section 13(S206;Y,S207;Y), the rewriting is executed(S208-S211).

Description

  The present invention relates to an electronic apparatus having a program control processor, and more particularly to a control method for reading a program from a nonvolatile memory such as a flash memory and starting it.

  NAND flash memory is used in many electronic devices because it has a simpler semiconductor structure than NOR flash memory and enables cost reduction. However, since data errors are likely to occur due to the structure, it is common to use error checking and correction (ECC) together. In particular, low-cost MLC (Multiple Level Cell) type NAND flash memories adopted in recent years are more susceptible to errors than SLC (Single Level Cell) type.

  Further, in a flash memory, a disturb phenomenon is known in which a high voltage applied at the time of erasing or writing data in a selected memory cell affects unselected memory cells and causes a data error (see Patent Document 1). . In particular, a portable communication device that reads and starts a program stored in a flash memory has a serious problem that the portable communication device does not start when an uncorrectable error occurs due to a disturb phenomenon. Therefore, there is a strong demand for sufficiently increasing the reliability of flash memory, and various methods for that purpose have been proposed.

  For example, in the storage device disclosed in Patent Document 1, program data is multiplexed and stored in a plurality of physical address areas, error detection / correction is executed when power is turned on, and data in an error-free area is used. Repair data in areas where uncorrectable errors occur. It has been recognized that this improves the reliability of recorded data and can prevent destruction of normal data even if the power is cut off during data restoration.

  According to the semiconductor device disclosed in Patent Document 2, the same boot program is stored in a plurality of blocks in the flash memory, and if the determination result of data read from one block is bad, the next block is read. If the determination is not bad, the data is output to the CPU.

  According to the flash memory system disclosed in Patent Document 3, data copies are stored at different locations in the flash memory, and the system is activated by selecting the best part from these copy data.

JP 2007-122640 A JP 2005-215824 A Special table 2007-518166 gazette

  However, as described above, the NAND flash memory is in a situation where data reliability is not sufficiently high due to the adoption of MLC. For this reason, there is a possibility that sufficient reliability cannot be secured by a method of storing the same data in a plurality of blocks or selecting and using a good portion from a plurality of data.

  In addition, it is sufficient that the original program can be restored while the spare program is operating, but it takes time to write data to the NAND flash memory. Therefore, if the battery of the portable device is exhausted during this time or if the user stops the power supply accidentally, the data in the NAND flash memory becomes abnormal and cannot be recovered only by subsequent reading.

  Furthermore, since the user generally does not have knowledge about the characteristics of the NAND flash memory, in a mobile communication device such as a mobile phone, memory management is usually performed in a state invisible to the user. However, this means that a critical process that may prevent the program from starting if the repair fails is performed without the user's knowledge. For this reason, there is a possibility that the user may perform some operation without knowing it, and it cannot be said that there is no possibility that the restoration of the program will fail due to the operation being turned off.

  As described above, the activation control method disclosed in the above-mentioned patent document cannot obtain sufficient reliability for activation because the possibility of power interruption cannot be excluded when the flash memory is restored.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a program activation control method for improving reliability when an electronic device is activated by reading a program from a nonvolatile memory, and an electronic device using the method.

  An electronic device according to the present invention is an electronic device having a display unit and an operation unit, and includes a plurality of nonvolatile storage means storing the same startup program for starting the electronic device, and a first nonvolatile storage An error detection means for detecting a data error in the first activation program read from the means, and when a data error in the first activation program is detected, the second activation program is read out from the second nonvolatile storage means; A program execution means for displaying a selection message as to whether or not to rewrite the first activation program with the second activation program on the display unit, and executing the rewriting when rewriting is selected through the operation unit; It is characterized by having.

  A program activation control method according to the present invention is a program activation control method in an electronic apparatus having a display unit, an operation unit, and a plurality of nonvolatile storage units storing the same activation program. When a data error in the first startup program read from the first nonvolatile storage means is detected, and the program execution means detects a data error in the first startup program, the second nonvolatile storage means outputs the second error. The startup program is read, and the program execution means displays a selection message as to whether or not to rewrite the first startup program with the second startup program on the display unit, and the program execution means includes the operation unit When rewriting is selected through the rewriting, the rewriting is executed.

  ADVANTAGE OF THE INVENTION According to this invention, the reliability at the time of starting an electronic device by reading a program from a non-volatile memory | storage means can be improved.

It is a block diagram which shows the functional structure of the electronic device by one Embodiment of this invention. 1 is a schematic diagram showing a general data structure of a NAND flash memory. It is a flowchart which shows the program starting control method by 1st Example of this invention. It is a top view of the portable communication apparatus which shows the example of a message displayed on the display part of the portable communication apparatus by 1st Example. It is a flowchart which shows the program starting control method by 2nd Example of this invention.

  Hereinafter, a mobile communication device will be taken as an example of an electronic device, and an embodiment of the present invention will be described in detail. The mobile communication device includes a mobile phone and a mobile information terminal having a communication function. However, the electronic device according to the present invention is not limited to this, and may be any device that executes a startup program stored in a non-volatile memory such as a flash memory by means of program execution means. In addition to PDA (Personal Digital Assistants), portable music players, electronic notebooks, laptop PCs, portable transceivers, and the like are also included.

1. Functional Configuration As shown in FIG. 1, a portable communication device according to an embodiment of the present invention includes a transmission / reception unit 11, a display unit 12, an operation unit 13, a power supply unit 14, and other functional units (not shown) controlled by a control unit 10. A speaker and a microphone functioning as a handset). The power supply unit 14 supplies power to the entire device from a battery (not shown), but the power supply voltage is monitored by the control unit 10. The transmission / reception unit 11 includes a wireless communication circuit for performing wireless communication with a base station of a mobile phone system, for example. The display unit 12 is a monitor for visually displaying various information to the user, and the operation unit 13 is a keypad or a touch panel, and enables manual operation by the user.

  The control unit 10 includes a program control processor (CPU (central processing unit)) 101 as program execution means, and a NAND flash memory (# 1) 102 and a NAND flash memory (# 2) connected to the CPU 101 via a common bus. 103 and a random access memory (RAM) 104 connected to the CPU 101 by another bus. The NAND flash memories 102 and 103 store the same startup program, but here, the NAND flash memory 102 marked “# 1” is an initially set program read memory, and “# 2” It is assumed that the described NAND flash memory 103 is a spare memory. The CPU 101 transfers a program from the NAND flash memory 102 or 103 to the RAM 104 in units of pages in accordance with a procedure to be described later, and starts the portable communication device by executing the transferred program.

  As shown in FIG. 2, the data in the NAND flash memories 102 and 103 is configured in units of pages and is written / read. Here, the program for n pages is stored as one block depending on the size of the program and the memory arrangement, and each page stores program data and its ECC data. For example, page 0 stores program data P0 and ECC data E0 calculated from the program P0. When the CPU 201 reads out the program data, the CPU 201 also reads out the ECC data to check whether there is an error in the program. The program uses different pages according to the functions that it implements, and in the case of functions that use a large amount, the program may span multiple blocks.

  The system according to this embodiment is activated by executing the activation program stored in the NAND flash memory 102 or 103. When the activation program is executed when the power is turned on, the CPU 101 first reads a program in a predetermined NAND flash memory 102 together with ECC data, and determines whether there is a data error using the ECC data. When an error is detected, the CPU 101 changes the program reading source from the predetermined NAND flash memory 102 to the spare NAND flash memory 103, and transfers the program from the NAND flash memory 103 to the RAM 104 for execution.

  According to this embodiment, after starting the program from the other NAND flash memory 103, the user is notified that an error has occurred in the mobile communication device, and stored in the NAND flash memory 102 on the side where the error has occurred due to the user operation. The rewriting of the programmed program can be selected. Furthermore, when program rewriting is selected, it is possible to determine whether or not to perform rewriting in consideration of the state of the battery power supply. Hereinafter, embodiments of the present invention will be described in detail.

2. First Embodiment A first embodiment of the present invention will be described in detail with reference to FIGS.

  In FIG. 3, when starting the startup operation, the CPU 101 transfers the startup program stored in the predetermined NAND flash memory (# 1) 102 to the RAM 104 together with the ECC data (step S201). The CPU 101 starts an error check of program data using the ECC data (step S202). When it is determined that there is no error in the read program (step S203; N), the control exits the flow of FIG. 3 and activates the mobile communication device with the program transferred to the RAM 104.

  If it is determined that there is an error in the read program (step S203; Y), the CPU 101 reads the program from another NAND flash memory (# 2) 103 and transfers it to the RAM 104 (step S204). At this time, ECC data may also be read simultaneously to perform error detection / correction. However, the NAND flash memory (# 2) 103 has a smaller number of times of writing / erasing than the normally used NAND flash memory (# 1) 102, so that an error hardly occurs and sufficient reliability can be maintained. When the program is transferred from the NAND flash memory (# 2) 103 to the RAM 104, the CPU 101 displays a message asking the user whether or not to perform maintenance on the display unit 12 of the mobile communication device (step S205). Specifically, a message as shown in FIG. 4A is displayed on the display unit 12, and an operation input of the operation unit 13 by the user is waited (step S206). This display informs the user that an ECC error has been detected and allows the user to select whether or not the memory # 1 can be rewritten.

  If there is a user operation input and it is to select maintenance execution (“START” in the example of FIG. 4A) (step S206; Y, step S207; Y), the user uses the NAND flash memory (# 1). ), The display unit 12 displays a message indicating “in maintenance” as shown in FIG. 4B to alert the user not to stop the power supply (step S208). ). After the display, the CPU 101 erases the data in the NAND flash memory (# 1) 102 as a maintenance operation (step 209), and the data in the normally operated NAND flash memory (# 2) 103 is stored in the NAND flash memory ( # 1) Write to 102 (step S210). When the data writing from the NAND flash memory (# 2) 103 to the NAND flash memory (# 1) 102 is completed (step S211; Y), the CPU 101 activates the portable communication device with the program transferred to the RAM 104.

  Note that if there is a user operation input and it selects maintenance non-execution (“END” in the example of FIG. 4A) (step S206; Y, step S207; N), the user will read the NAND flash memory. The CPU 101 activates the portable communication device with the program transferred from the NAND flash memory (# 2) 103 to the RAM 204 without rewriting the program in the NAND flash memory (# 1) 102. To do.

  As described above, the present embodiment has the following effects.

  The first effect is that even if an error occurs in the NAND flash memory (# 1) 102 in which the program is stored due to a disturb phenomenon or the like, another NAND flash memory ( # 2) The mobile communication device can be activated using the program 103.

  The second effect is that the data in the NAND flash memory (# 2) 103 is written next time after the NAND flash memory (# 1) 102 is erased after being started by the program of the NAND flash memory (# 2) 103. To the NAND flash memory (# 1) 102.

  The third effect is that there is no expertise of the NAND flash memory by displaying that the maintenance is necessary on the display unit 12 before starting the erasing / writing of the NAND flash memory (# 1) 102 for recovery. The user can be alerted, and data restoration failure due to user operation can be avoided.

  As a fourth effect, the user can select whether or not to perform maintenance, and further display the fact that the maintenance operation is being performed, thereby making it possible to strongly impress the user on the status of the mobile communication device. Accordingly, it is possible to prevent an operation of stopping power supply during erasing / writing of the NAND flash memory, and it is possible to reliably avoid a situation in which the program data stored in the NAND flash memory is destroyed and the program is not started.

3. Second Embodiment A second embodiment of the present invention will be described in detail with reference to FIG. However, the same steps as those in FIG.

  In FIG. 5, when the CPU 101 starts the activation operation, it transfers the program stored in the predetermined NAND flash memory (# 1) 102 to the RAM 104 together with its ECC data (step S201). The CPU 101 starts an error check of program data using the ECC data (step S202). When it is determined that there is no error in the read program (step S203; N), the control exits the flow of FIG. 3 and activates the mobile communication device with the program transferred to the RAM 104. If it is determined that there is an error in the read program (step S203; Y), the CPU 101 reads the program data from another NAND flash memory (# 2) 103 and transfers it to the RAM 104 (step S204).

  When the program is transferred from the NAND flash memory (# 2) 103 to the RAM 104, the CPU 101 displays a message asking the user whether or not maintenance is to be performed on the display unit 12 of the portable communication device. Wait for selection input (step S401). When maintenance execution (“START” in the example of FIG. 4A) is selected (step S401; Y), the CPU 101 compares the power supply voltage of the power supply unit 14 with a predetermined threshold Vth to estimate the remaining battery power ( Step S402). If the remaining battery capacity is sufficient for rewriting the program (step S402; Y), the program in the NAND flash memory (# 1) 102 is rewritten by executing steps S208 to S211 described above.

  If the remaining battery level is insufficient for rewriting the program (step S402; N), the CPU 101 displays the necessity for charging on the display unit 12 to alert the user and program the NAND flash memory (# 1) 102. Without rewriting, the portable communication device is activated by the program transferred from the NAND flash memory (# 2) 103 to the RAM 204.

  In the second embodiment described above, the same effects as in the first embodiment described above can be obtained, and furthermore, the power supply is stopped due to the battery running out during erasing / writing of the NAND flash memory, and stored in the NAND flash memory. It is possible to reliably avoid a situation in which the programmed program data is destroyed and the program does not start.

4). Other Embodiments The present invention is not limited to the above-described embodiments, but should be understood as including the following modifications. For example, in FIG. 1, the NAND flash memory 102 and the NAND flash memory 103 are separately described, but these may be configured by different areas (different blocks) of one NAND flash memory.

  Further, since the NAND flash memory 103 is used for storing a program, it may be a non-volatile memory, and the interface with the CPU 101 may be different from that of the specific NAND flash 102. The same effect can be obtained even with different types of memories such as NOR flash memory and PRAM (Phase Change RAM). The NAND flash memory 103 may be a removable memory card.

  Further, in the first and second embodiments, the CPU 201 performs an error check on the program data. However, some NAND flash memories have a built-in ECC error check function, and the CPU 101 itself performs the ECC calculation using them. The same effect can be obtained even if only error confirmation is performed without performing this.

  Note that the message on the display unit 12 illustrated in FIG. 4 is an example, and any message may be used as long as the same content is instructed. Also, the layout of buttons on the operation unit 13 is arbitrary.

  The present invention is applicable to portable devices such as a cellular phone, a PDA, a portable music player, an electronic notebook, a laptop PC, and a transceiver.

DESCRIPTION OF SYMBOLS 10 Control part 11 Transmission / reception part 12 Display part 13 Operation part 14 Power supply part 101 CPU
102 NAND flash memory 103 NAND flash memory 104 RAM

Claims (8)

An electronic device having a display unit and an operation unit,
A plurality of nonvolatile storage means storing the same activation program for activating the electronic device;
Error detection means for detecting a data error in the first activation program read from the first nonvolatile storage means;
When a data error in the first activation program is detected, the second activation program is read from the second nonvolatile storage means, and whether or not the first activation program is rewritten with the second activation program is selected. A program execution means for displaying a message on the display unit and executing the rewrite when rewrite is selected through the operation unit;
An electronic device comprising:   The electronic device according to claim 1, wherein when the rewriting is selected and executed, the program execution unit displays a message indicating that rewriting is being performed on the display unit.   The electronic device according to claim 2, wherein the message indicating that rewriting is in progress includes a word prohibiting power supply from being stopped. Further comprising power monitoring means for estimating a remaining amount of a battery serving as a power source for the electronic device,
The said program execution means displays the message which urges | charges on the said display part, without performing the said rewriting, when the remaining amount of the said battery is less than a predetermined threshold value. The electronic device described. A program activation control method in an electronic device having a display unit, an operation unit, and a plurality of storage units storing the same activation program,
The error detection means detects a data error in the first activation program read from the first nonvolatile storage means;
When the program execution means detects a data error in the first activation program, the program execution means reads the second activation program from the second nonvolatile storage means,
The program execution means causes the display unit to display a selection message as to whether or not to rewrite the first activation program with the second activation program;
The program execution means executes the rewrite when rewrite is selected through the operation unit;
And a program start control method. When the rewriting is selected and executed, the program execution means displays a message indicating that rewriting is being performed on the display unit.
6. The program start control method according to claim 5, wherein   The program start control method according to claim 6, wherein the message indicating that rewriting is in progress includes a word prohibiting the power supply from being stopped. The power monitoring means estimates the remaining amount of the battery serving as a power source for the electronic device,
The program execution means displays a message prompting charging on the display unit without executing the rewriting when the remaining amount of the battery is less than a predetermined threshold.
The program activation control method according to claim 5, wherein the program activation control method is defined.

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