JP4239657B2 - Electronics - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a cost reduction of an electronic device that needs to store a program in a writable non-volatile memory, and particularly relates to the realization of a cost reduction by introducing a NAND flash, which is an inexpensive writable non-volatile memory, into the electronic device. is there.
[0002]
[Prior art]
As a conventional example of reducing the cost of electronic equipment using a nonvolatile semiconductor memory, data that cannot be rewritten is stored in a mask ROM that is a type of nonvolatile memory that can only be read, and data that can be rewritten Is stored in a writable nonvolatile memory (see Patent Document 1).
[0003]
FIG. 5 is a block diagram showing the configuration of the conventional electronic device.
[0004]
In FIG. 5, 51 is a system bus, 52 is a bus interface controller, 53 is a data controller, 54 is a flash memory, 55 is a mask ROM, and 56 is a data storage area.
[0005]
Hereinafter, a conventional example will be described with reference to FIG.
[0006]
The data storage area 56 includes a flash memory 54 and an inexpensive mask ROM 55. Here, of the data, data that cannot be rewritten is stored in the inexpensive mask ROM 55, and the flash memory 54 stores data that can be rewritten.
[0007]
This realizes proper use of memory depending on data, reduces the cost of a recording medium that conventionally stores data only in an expensive flash memory memory, and reduces the cost of electronic equipment.
[0008]
[Patent Document 1]
Japanese Patent Laid-Open No. 06-168599 [0009]
[Problems to be solved by the invention]
In an electronic device such as a digital broadcast receiver, there is a possibility that the device program is rewritten by downloading, and there is little data that cannot be rewritten, and it is difficult to reduce the cost by using a mask ROM. Therefore, there is a problem that the cost reduction effect of the conventional example is small.
[0010]
In digital broadcast receivers, the capacity of applications and device control programs tends to increase, and it is also necessary to store program guide data in a rewritable nonvolatile memory, and the required capacity of a rewritable nonvolatile memory is enormous. Therefore, cost reduction is an even greater challenge.
[0011]
In recent years, NAND flash memory has been used in memory cards such as smart cards for storing data, so that NAND flash memory can be used as a nonvolatile memory for digital broadcast receivers. It can be considered to be used as a memory.
[0012]
However, the NAND flash memory has a possibility that an error may occur at the time of reading, and an error correction is possible in the case of a 1-bit error, but there is a problem that an error of 2 bits or more cannot be corrected. Therefore, in the NAND flash memory, there is a possibility that an error of 2 bits or more occurs in the program data. If an error of 2 bits or more occurs, the program cannot be executed, and the NAND flash memory cannot be used for storing programs. (Reference: CQ publisher TECHI interface special issue PC card / memory card thorough research P.200 “Chapter 7 Overview of SmartMedia (Hiroshi Sukegawa / Hayato Maesako)”).
[0013]
[Means for Solving the Problems]
In order to solve the above problem, in the present invention, as a first invention, program data, management data, and application data of an electronic device are stored in one inexpensive and large-scale rewritable NAND flash memory, and these data are stored. If there is no data that cannot be corrected, the program is executed. If there is data that cannot be corrected, management data (memory usage information, memory division information, memory failure area information, electronic device operation) In the case of (environment / setting, etc.), a backup of management data is prepared in advance, and error correction is performed by selecting management data capable of error correction from the backup. In the case where error correction is impossible in the device program, electronic data for fetching the program data of the uncorrectable error part from an external memory such as a PC card or a CD ROM that stores the program in advance and executing the program after correcting the error Provide equipment.
[0014]
In the second invention, if there is uncorrectable data in the program data in the first invention, the network of the device manufacturer is accessed via the network, and the program data corresponding to the uncorrectable error portion of the device program is fetched. An electronic device that executes a program after correcting an error is provided.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of an electronic device according to the present invention will be described in detail below with reference to the drawings.
[0016]
(Embodiment 1)
FIG. 1 is a block diagram showing a configuration of an electronic apparatus according to Embodiment 1 of the present invention. FIG. 2 is an explanatory diagram of the electronic apparatus according to the first embodiment.
[0017]
In FIG. 1, 1 is a system bus, 2 is an external interface unit, 3 is a CPU, 4 is a main memory for the CPU, 5 is a NAND flash memory control unit,
6 is a mask ROM, 7 is a NAND flash memory, 8 is an electronic device, 9 is an interface bus with an external memory, and 10 is an external memory.
[0018]
Hereinafter, a digital broadcast receiver will be described as an example with reference to FIGS.
[0019]
The NAND flash 7 stores digital broadcast receiver program data, application data such as NAND flash memory and electronic device management data, and program guide data.
[0020]
FIG. 6 is an explanatory diagram of an example of NAND flash memory management information.
[0021]
Reference numeral 61 denotes an entire NAND flash memory space, 62 a management information storage unit, 63 a program data storage unit, and 64 a program information storage unit.
[0022]
The management information storage unit 62 stores memory usage information (memory division) and defective block information of the NAND flash memory 7 in addition to user-specific data such as the operating environment (remote control settings, etc.) of the digital broadcast receiver. A plurality of backup data are stored. Note that the management data has a smaller data capacity to be stored than the device program data and application data, so even if a plurality of backup data is prepared, the influence on the cost increase is small.
[0023]
Further, the mask ROM 6 has a program for controlling the NAND flash memory control unit 5 for transferring various data stored in the NAND flash memory 7 from the NAND flash memory 7 to the main memory 4 and data errors in the NAND flash memory 7. A program for performing detection and correction and a program for controlling the external interface unit 2 for interfacing with the external memory 10 are stored.
[0024]
When the digital broadcast receiver is activated (S1), the CPU 3 activates a program stored in the mask ROM 6 (S2), and transfers various data from the NAND flash memory 7 to the main memory 4 (S3).
[0025]
In this transfer, the NAND flash memory control unit 5 performs error detection (S4, S5) on the data read from the NAND flash memory 7, and there is no error (no correction required), 1 bit error (correctable), 2 bit or more error In the case of a 1-bit error, the CPU notifies the CPU of the location of the error in order to correct the error. Based on this information, if there is no error, the CPU executes the program with the management data, program, and application data transferred from the NAND flash.
[0026]
If error correction is possible, error correction (S6) is performed by inverting the data at the error location, and then the program is executed.
[0027]
Here, in the NAND flash memory control unit 5, when reading from the NAND flash memory 7, the CPU performs based on the NAND flash memory management information, so that the currently transferred data is digital broadcast receiver program data or program guide data. Thus, it is possible to know the application data, and the address of each data, so that the error correction can be performed.
[0028]
Next, a case where an error that cannot be corrected occurs will be described.
[0029]
Transfer from the management data stored in the NAND flash memory 7 to the main memory 4 is started first, but when error correction is impossible in the management data (S9), a plurality of managements of the NAND flash memory 7 are performed. Data that can be corrected for error is selected from the data backup data and used as management data (S10). Since the management data has a smaller storage capacity than the program data and application data, the configuration of the present invention does not increase the cost.
[0030]
If the management data can be acquired without any problems, the device program data is transferred next.
[0031]
At this time, if error correction is impossible, an error message is presented by voice or graphics to the operator of the digital broadcast receiver 8 (S11). For example, “There is a problem in the system, please insert the external memory 10 provided by the manufacturer of the digital broadcast receiver 8”.
[0032]
With this message, the operator of the digital broadcast receiver 8 inserts the external memory 10 provided by the manufacturer of the digital broadcast receiver 8 into the digital broadcast receiver 8.
[0033]
The CPU 3 obtains the location (address) of the program in which an error that cannot be corrected has occurred from the NAND flash memory control unit 7, and loads this portion of the program from the external memory 10 (S12, 13). Since the uncorrectable error can be repaired by completing the loading from the external memory 10, a repair completion message is presented by voice or graphics (S14). For example, “System trouble has been repaired. Inconvenience. You can remove the external memory 10 provided by the manufacturer of the digital broadcast receiver 8”.
[0034]
Since the program has been completely repaired, the program can be executed from the main memory (S7). After the execution of the program, the error occurrence frequency when the power is turned on next time can be greatly suppressed by updating the data of the error location in the NAND flash memory 7 (S8).
[0035]
When an error that cannot be corrected occurs in the application data, the program is executed without correcting the error, and the application data is updated or reset after the program operates normally. For example, when the program data becomes uncorrectable during digital broadcast reception, the data at the error location in the NAND flash memory 7 is updated after the data is acquired again from the air.
[0036]
As a result, since only management data needs to be backed up, the capacity of the NAND flash memory can be reduced and the cost can be reduced.
[0037]
Further, in the error repair method of the first embodiment, there is a problem that when the program data is updated, it cannot be updated to the latest program. However, in the case of a digital broadcast receiver, the next digital broadcast system after the error is repaired It is possible to update to the latest program by downloading the program data. In addition, by accessing the equipment manufacturer with a personal computer or the like and obtaining the latest program data, it is possible to update to the latest program without waiting for the program data to be downloaded in the digital broadcasting system.
[0038]
Further, when an error that cannot be corrected occurs, the error occurrence content is stored in the management data block of the NAND flash memory 7, so that even if the process is interrupted during error recovery, the next time the electronic device is trajected It is possible to perform error repair again.
[0039]
The external memory 10 includes a PC card or an optical disk.
[0040]
(Embodiment 2)
FIG. 3 is a block diagram showing a configuration of an electronic apparatus according to the second embodiment of the present invention. FIG. 4 is an explanatory diagram of the electronic apparatus according to the second embodiment.
[0041]
In FIG. 2, 21 is a system bus, 22 is an external interface unit, 23 is a CPU, 24 is a main memory for the CPU, 25 is a NAND flash memory control unit,
26 is a mask ROM, 27 is a NAND flash memory, 28 is an electronic device, 29 is a public line / ISDN network, and 30 is a manufacturer of a digital broadcast receiver.
[0042]
Hereinafter, a digital broadcast receiver will be described as an example with reference to FIGS.
[0043]
The NAND flash 27 stores program data for digital broadcast receivers, application data such as NAND flash memory and electronic device management data, and program guide data (see FIG. 6). In the mask ROM 26, a program for controlling the NAND flash memory control unit 25 for transferring various data stored in the NAND flash memory 27 from the NAND flash memory 27 to the main memory 24, and data errors in the NAND flash memory 27 are stored. A program for performing detection and correction, and a program for controlling the external interface unit 22 for accessing the digital broadcast receiver manufacturer 30 and a network including a public line, ISDN network, or LAN are stored.
[0044]
When the digital broadcast receiver is activated (S21), the CPU 23 activates a program stored in the mask ROM 26 (S22), and transfers various data from the NAND flash memory 27 to the main memory 24 (S23).
[0045]
Based on this information, if there is no error, the CPU executes the program with the management data, program, and application data transferred from the NAND flash.
[0046]
If error correction is possible, error correction (S26) is performed by inverting the data at the error location, and then the program is executed.
[0047]
Here, in the NAND flash memory control unit 25, when reading from the NAND flash memory 27, the CPU performs based on the NAND flash memory management information. Therefore, the currently transferred data is the program data for the digital broadcast receiver or the program guide data. Thus, it is possible to know the application data, and the address of each data, so that the error correction can be performed.
[0048]
Next, a case where an error that cannot be corrected occurs will be described.
[0049]
First, transfer from the management data stored in the NAND flash memory 27 to the main memory 24 is started. When error correction is impossible in the management data (S29), a plurality of managements of the NAND flash memory 27 are performed. Data that can be error-corrected is selected from the data backup data and used as management data (S30). Since the management data has a smaller storage capacity than the program data and application data, the configuration of the present invention does not increase the cost.
[0050]
If the management data can be acquired without any problems, the device program data is transferred next.
[0051]
If the program data has an error of 2 bits or more (cannot be corrected), an error message is presented by voice or graphics to the operator of the digital broadcast receiver 28 (S31). For example, “There is a problem with the system, and the digital broadcast receiver manufacturer is being accessed.
[0052]
The CPU 23 obtains the location (address) of the program in which an error that cannot be corrected has occurred from the NAND flash memory control unit 27, and loads this portion of the program from the digital broadcast receiver manufacturer 30 (S32, 33). Since the uncorrectable error can be repaired by completing the loading from the digital broadcast receiver manufacturer 30, a repair completion message is presented by voice or graphics (S34). For example, “System trouble has been repaired.
[0053]
Since the program has been completely repaired, the program can be executed from the main memory (S27). After the program is executed, the error occurrence frequency when the power is turned on next time can be significantly suppressed by updating the data of the error location in the NAND flash memory 27 (S28).
[0054]
It should be noted that when data other than the program, for example, the program information data of the digital broadcast receiver becomes uncorrectable, it will not be a fatal problem. Therefore, after acquiring the program information data again from the on-air, the NAND flash memory 7 Update the data at the error location. As a result, since only management data needs to be backed up, the capacity of the NAND flash memory can be reduced and the cost can be reduced.
[0055]
Further, when an error that cannot be corrected occurs, the error occurrence content is stored in the management data block of the NAND flash memory 27, so that even if the process is interrupted during error correction, the next time the electronic device is trajected It is possible to perform error repair again.
[0056]
In the second embodiment, since it can be updated to the latest program via the network, it is not necessary to wait for program data download in the digital broadcasting system as in the first embodiment, and the latest program is not required. It can be updated to other programs.
[0057]
Further, according to the present invention, since the data capacity to be stored is small with respect to the management data, the management data is backed up because it is considered that there is no significant effect on the cost increase even if a plurality of backups are stored. However, if the cost increase is affected, the method of backing up to the external memory in the first invention and the method of backing up via the network of the second invention can be handled.
[0058]
【The invention's effect】
According to the electronic apparatus of the present invention, an inexpensive and large-scale rewritable NAND flash memory can be used as a program storage memory. Further, since data to be backed up can be minimized and program data, management data, and application data of the electronic device can be stored in one NAND flash memory, it is effective in reducing the cost of the electronic device, particularly the digital broadcast receiver.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of an electronic device according to a first embodiment of the present invention. FIG. 2 is an operation explanatory diagram of the electronic device according to a first embodiment of the present invention. FIG. 4 is a block diagram showing the operation of the electronic device according to the second embodiment of the present invention. FIG. 5 is a block diagram showing the configuration of the conventional electronic device. FIG. Figure showing an example [Explanation of symbols]
1 System bus 2 External interface controller 3 CPU
4 Main memory 5 NAND flash memory controller 6 Mask ROM
7 NAND flash memory 8 electronic device 9 external memory interface bus 10 external memory 21 system bus 22 external interface control unit 23 CPU
24 Main memory 25 NAND flash memory controller 26 Mask ROM
27 NAND flash memory 28 Electronic device 29 Public line / ISDN network 30 Digital broadcast receiver manufacturer 51 System bus 52 Bus interface controller 53 Data controller 54 Flash memory 55 Mask ROM
56 Storage Area 61 NAND Flash Memory Total Space 62 Management Data Storage Unit 63 Program Data Storage Unit 64 Program Information Storage Unit

Claims (7)

A readable and writable first non-volatile recording unit that stores at least a control program for controlling an electronic device and management data;
A main storage unit for transferring and storing information from the first non-volatile recording unit;
An external interface control unit for controlling an interface to an external memory or network connectable to the electronic device;
A second non-volatile recording unit capable of reading only, storing a program for transferring information from the first non-volatile recording unit to the main storage unit and controlling the external interface control unit;
A CPU that executes a program for transferring information from the first nonvolatile recording unit stored in the second nonvolatile recording unit to the main storage unit, and then executes a control program for the electronic device;
A memory control unit that detects and corrects errors that occur in the first non-volatile recording unit,
When the memory control unit detects that the error correction is impossible in the first nonvolatile recording unit and the error detection is the control program or the management data, the second nonvolatile recording unit A control program or management data is acquired by the external interface control unit based on a program for controlling the external interface control unit stored in the unit, and stored in the first nonvolatile recording unit. Electronic equipment.   The first non-volatile recording unit further stores application data of an electronic device, and the memory control unit cannot perform error correction and detects an error in the first non-volatile recording unit. In the case of the application data, after executing the control program and management data, the external interface control unit based on a program for controlling the external interface control unit stored in the second nonvolatile recording unit 2. The electronic device according to claim 1, wherein the application data is acquired and stored in the first nonvolatile recording unit.   The electronic device according to claim 1, wherein the external memory includes a PC card or an optical disk. The electronic device further includes an output unit that outputs audio or video to the outside of the electronic device, and an error that cannot be corrected in the first nonvolatile recording unit has occurred in the memory control unit. the when detecting, by the output unit, electronic apparatus according to any one of claims 1 to 3, and outputs a video or audio requires connection to the external memory to the external interface controller. The network, the electronic device according to any one of claims 1 to 4, characterized in that it comprises a public line or LAN.   6. The electronic device according to claim 5, wherein the network is connected to a network of the electronic device manufacturer, and the control program of the electronic device can be acquired through the network. The said 1st non-volatile recording part is comprised by NAND type flash, and the said 2nd non-volatile recording part is comprised by ROM , The any one of Claim 1 to 6 characterized by the above-mentioned. Electronic equipment.

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