JPH09265391A - Controller with program rom correction function, electronic equipment provided with the controller and correction method for program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic equipment without the need of simultaneously switching a microcomputer and a memory in the case of using a program ROM correction function and preparing nonvolatile memories for the same number as produced versions by a service department. SOLUTION: The correction data of the plural versions are paired with ID numbers and stored in the nonvolatile memory 24 corresponding to the version of a CPU 12 and collation with the ID number for indicating the version intrinsic to the CPU stored inside a program ROM 16 storing the operation procedure of the CPU is performed. When the ID numbers do not match with each other, the ID number paired with the correction data of the other version is read corresponding to an address stored along with the pertinent ID number of the nonvolatile memory and the collation is performed further. Only when the ID numbers match with each other, the correction of a program is executed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device having a program ROM correction function having a microcomputer and an electronic apparatus having the control device, and more particularly to a program ROM having a nonvolatile memory and a microcomputer having a program ROM correction function. The present invention relates to a control device with a correction function and an electronic device having the control device.

[0002]

2. Description of the Related Art As the price of microcomputers has become lower and popular, various electronic devices have come to be controlled by microcomputers. Electronic devices equipped with a microcomputer include a television receiver (television), a VTR, a CD player, and the like.
Microcomputers are widely used for controlling air conditioners, refrigerators, ovens, microwave ovens, and the like. A so-called one-chip microcomputer in which a CPU, a memory, and the like are incorporated in one chip is generally used as a microcomputer mounted on such an electronic device.

Usually, when manufacturing such a microcomputer,
It is necessary to finish programming a certain period before the time when an unalterable final product called mask product is made. This is because it takes several weeks to several months to mask the program after it is completed.
During this period, it is often the case that defects such as program changes and program bugs due to hardware configuration changes are discovered.

In such a case, it is general to use a program ROM correction function called ROM CORRECTION (ROM correction) to correct the masked program. The ROM correction is a function of storing correction data in a non-volatile memory and correcting some data of the masked program. The method is to use the hardware built into the microcomputer and the program, that is, hold the correction data of the address of the part to be corrected in the program in the non-volatile memory and use the function of the microcomputer hardware corresponding to the ROM correction in the program. There is a method of changing data at a certain address, a method of storing a program in a memory and reading the program into a RAM and using the RAM area as if it were a program area.

In any case, since the correction data stored in the non-volatile memory is data dedicated to the program to be corrected, it must be paired with the program.
When the program is upgraded, the correction data stored in the non-volatile memory for the previous program must be disabled.

Conventionally, as a method, an ID number such as a version number is held as data in a program of a microcomputer, and data to be stored in a nonvolatile memory is stored in a microcomputer in addition to correction data. I was taking the method of remembering the same ID number that I had. Before reading the correction data, the ID number held in the microcomputer program and the ID number stored in the non-volatile memory are subjected to a matching check, and if they are equal, the correction data for the microcomputer is read. Correct the data. The flowchart in that case is shown in FIG.
Shown in

In step S101, the ID number (memory ID) is read from the address of the non-volatile memory designated by the program. In step S102, a matching check is performed to determine whether the ID number (microcomputer ID) held in the program is equal to the read memory ID. If they are equal, the correction data is read from the non-volatile memory in step S103, and the process returns to the regular process. After that, the defects of the program will be corrected. If the microcomputer ID and the memory ID are different in step S102, it is determined that the correction data is not suitable for the microcomputer program, and the routine returns to the steady process without reading the correction data from the nonvolatile memory.

[0008]

According to this method, when the version of the microcomputer program is switched, the ROM collection is used in the old version, and the new version already has a defect, so that the ROM collection is not used. In such a case, the nonvolatile memory must be changed to one in which the correction data and the ID number correspond to the new version at the same timing as the version switching of the microcomputer at the time of manufacture. However, in the actual manufacturing process, it is difficult to make the switching timings of the microcomputer and the non-volatile memory exactly the same in this way. However, if they are not switched at the same time, a different version of the correction data is included, and a set in which the correction data cannot be properly read will be shipped.

In addition, if the version is updated several times and each has a defect, each version must have a non-volatile memory. A suitable non-volatile memory must be supplied for each case.

The masked microcomputer has some defects in the program, and when the program ROM correction function called ROM correction is used, the correction data can be stored only for one conventional version of the program. In the case where the ROM correction must be used in both versions due to the version switching, there was a problem that the microcomputer and the memory had to be switched at the same time.

Further, since the correction data must be paired with the program, it is necessary to use a fixed memory for a certain version, and when the ROM correction is used, a service department is created. There was a problem that it was necessary to prepare as many non-volatile memories as there were versions.

Therefore, according to the present invention, when the program ROM correction function is used, it is not necessary to switch the microcomputer and the memory at the same time, and it is necessary for the service department to prepare the same number of nonvolatile memories as the prepared version. An object of the present invention is to provide a control device with a program ROM correction function and an electronic device having the control device.

[0013]

In order to achieve the above object, according to the present invention, a plurality of versions of correction data are stored in a non-volatile memory so as to correspond to CPU versions in pairs with ID numbers. When the ID numbers do not match each other, it is stored together with the ID number of the non-volatile memory. According to the address, the ID number paired with the correction data of another version is read and further collated, and the program is corrected only when the ID numbers match each other.

That is, according to the present invention, a CPU, a program ROM storing the operation procedure of the CPU,
Corresponding to the version of the program ROM, the CP
A nonvolatile memory in which data for correcting the U ID number and the contents of the program ROM is written; and a means for reading the ID number stored in the nonvolatile memory,
Means for determining whether the read ID number is equal to the ID number written in the program ROM, and, as a result of the determination, correct data corresponding to the program from the non-volatile memory only when the ID numbers are equal. In a control device with a program ROM correction function having a means for permitting reading, one predetermined address is written in advance in the nonvolatile memory in correspondence with one ID number, and the result of determining the ID number If the two are not equal, the IDs stored in the non-volatile memory
Means for reading another ID number from the address stored together with the number and determining again whether or not the ID numbers are the same, and as a result of the determination, correspond to the program from the nonvolatile memory only when the ID numbers are the same. And a means for permitting reading of the corrected data, and a control device with a program ROM correction function is provided.

Further, according to the present invention, there is provided an electronic device having a controlled device, which corresponds to a CPU, a program ROM storing the operation procedure of the CPU, and a version of the program ROM. ID number and the data for correcting the contents of the program ROM are written in the nonvolatile memory, a means for reading the ID number stored in the nonvolatile memory, and the read ID
Means for determining whether the number is equal to the ID number written in the program ROM, and the result of the determination, the ID
An electronic device configured to control the control target device by a control device with a program ROM correction function, which has a means for permitting reading of correction data corresponding to a program from the nonvolatile memory only when the numbers are the same. In the device, one predetermined address corresponding to one ID number is written in advance in the non-volatile memory, and if the ID numbers are not equal as a result of judging the ID numbers, they are stored in the non-volatile memory. Means for reading another ID number from the address stored together with the ID number and determining again whether or not the ID numbers are the same, and only when the determination results show that the ID numbers are the same, the nonvolatile memory stores a program. And a means for permitting reading of corresponding correction data. An electronic device having a OM correction function control device is provided.

Further, according to the present invention, a CPU, a program ROM storing the operation procedure of the CPU,
In a method for correcting a program in a program ROM of a microcomputer having a nonvolatile memory connection portion to which a nonvolatile memory in which correction data of a program in the program ROM is written can be detachably mounted, a plurality of nonvolatile memories are previously stored in the nonvolatile memory. When the correction data of the corrected version is written, and each correction version is written together with one ID number, and the program of the program ROM is corrected, the nonvolatile memory is set to the nonvolatile memory. Attaching to the memory connection part, reading the ID number stored in the non-volatile memory, and reading the ID number from the program ROM.
And a step of permitting reading of the correction data corresponding to the program from the nonvolatile memory only when the ID numbers are equal as a result of the determination. If the ID numbers are not equal as a result of the determination of the ID numbers, another ID number is read from the address stored together with the ID number stored in the non-volatile memory, and the I number is read again.
The method further comprises a step of determining whether or not the D numbers are the same, and a step of permitting the correction data corresponding to the program to be read from the non-volatile memory only when the ID numbers are the same as a result of the determination. A method for correcting a program is provided.

According to the present invention, another ID number in the non-volatile memory is recorded when it is determined that the non-equalities are not equal to each other in the non-volatile memory as a result of matching check of the ID number and the correction data. By having address information, a plurality of ID numbers and a plurality of correction data associated therewith are stored in the non-volatile memory, and suitable correction data is read from the non-volatile memory subjected to matching check with the ID number of the microcomputer. be able to. Also,
If there is a need to change the version of the microcomputer at the time of manufacture, and if you need correction data for both the previous version and the later version, change it to a nonvolatile memory that contains both data in advance. Even if the switching timing of the non-volatile memory does not exactly match,
You can incorporate the correct modification data for each version.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a control device with a program ROM correction function and an electronic apparatus having the control device according to the present invention will be described below with reference to the accompanying drawings. FIG. 2 is a block diagram showing the entire control device with a program ROM correction function of the present invention and a part of electronic equipment having the control device. The electronic device 20 is, for example, a television, and a controlled device 22 that is a part of the electronic device 20 and a microcomputer 10 that controls the device 22 are shown. Controlled device 2
2, for example, the frequency setting of the tuner of the TV,
Although there is an AV selector and the like, the content of the control target device 22 is not directly related to the present invention, and therefore its explanation is omitted.

The microcomputer 10 is a central processing unit C
It has a PU 12, a RAM 14 as a writable memory, a ROM 16 as a read-only memory, and an input / output interface (I / F) 18, and these elements are built in one board and configured as a one-chip microcomputer. ing. The microcomputer 10 can send and receive signals to and from the controlled device 22 via the interface 18, and also can send and receive signals to and from the nonvolatile memory 24.
The non-volatile memory 24 itself is a single-chip unit, and is attachable to and detachable from a socket provided on a substrate (not shown) of the electronic device 20.

The ROM 16 has the same contents as a normal computer.
The operation procedure of the CPU 12 is stored as a program, and the CPU 12 reads this program and performs an operation according to the instruction to execute a predetermined control for the controlled device 22. Although the CPU 12 is mass-produced, the hardware configuration, that is, the architecture, is improved as needed, and therefore the contents may be partially different even if the CPUs are of the same type. This improvement is generally referred to as a version upgrade, and can be identified from the chip-specific serial number printed on the outside of the CPU casing. The CPU version is the one used when correcting the program in the ROM 16, that is, the nonvolatile memory 2
It is necessary to make a correction as if the program itself of the ROM 16 was changed by using 4.
It is written in a predetermined area of the OM 16 in advance.

The non-volatile memory 24 stores data for correction when the program of the ROM 16 needs to be corrected. As shown in FIG. 3, a plurality of data corresponding to a plurality of versions of the CPU 12 are stored. The correction data of the version is stored. Now, as shown in FIG. 3, two versions of the correction data group, correction data and correction data, are stored in correspondence with the ID number and the ID number, respectively. Further, the storage area for the ID number has the following I
The address of the ID number, which is the D number, is also stored. Since there are two correction data groups in this example, it is not necessary to store the address of the next ID number in the ID number area. However, if a total of four correction data groups are stored, the first to third The following ID numbers, that is, the second to fourth IDs, are stored in the ID number areas
The address of the number will be stored together. In addition,
Although 4 bytes are assigned to the ID number and 2 bytes are assigned to the address, the number can be increased or decreased as necessary.

Now, assuming that there are two corrected versions of the program in the ROM 16, the non-volatile memory 24 in which two groups of correction data are stored is inserted into the non-volatile memory socket as shown in FIG. When the power of the electronic device 20 is turned on in this state, the CPU 12 is activated and executes the operation according to the flowchart shown in FIG. In step S201, the ID number (memory ID) is read from the determined address in the nonvolatile memory 24. Here, the memory ID is an ID number written in the non-volatile memory 24 and indicates a correction data group corresponding to a predetermined CPU version. The ID number (microcomputer ID) held in the program in step S202,
That is, a matching check (collation) between the ID number read from the ROM 16 and the memory ID is performed. The microcomputer ID is an ID number stored in advance in the ROM 16 and indicates the version of the CPU. As a result of this comparison, if the ID numbers are the same, the correction data is read from the non-volatile memory in step S203, and the routine returns. After that, the defects of the program will be corrected.

On the other hand, if the memory ID and the microcomputer ID are not equal as a result of the matching check in step S202, the jump destination address stored together with the memory ID is read (step S204). Then, in step S205, the memory ID written in the jump destination address read in step S204 is read. In step S206, the microcomputer ID and the memory ID are again checked for matching (matching). If they are equal, the correction data is read from the nonvolatile memory in step S207 and the routine returns. Microcomputer ID in step S206
And the memory ID are different, it is determined that there is no ROM collection suitable for the microcomputer program, and the routine returns to the regular processing.

Here, for the sake of convenience, if the result of the matching check in step S206 is different, the process returns to the steady process. However, as described above, when there are three or more correction data groups, the process is skipped again together with the memory ID. By writing the destination address, the memory ID written in the destination address can be read. By repeating this, it is possible to store several versions of correction data. When actually used, it seems that it is not necessary to support a large number of versions, and it can be said that it is desirable to set the jump address several times or so in order to prevent malfunctions. Therefore, for example, when the number of times the destination address has been designated reaches 4, it is possible to forcibly return to the regular processing without further jumping. Alternatively, in order to compulsorily notify that there is no jump destination address, for example, if an FF in hexadecimal notation that is predetermined data is written, the process is exited.

[0025]

As described above, according to the control device with a program ROM correction function and the electronic device having the control device of the present invention, not only the ID number but also the jump destination address are recorded in the nonvolatile memory. Thus, the ID number matching check can be performed a plurality of times when the ROM correction function is used. Therefore, when the version of the microcomputer program is changed on the manufacturing line and the ROM correction function is used for both versions, the version can be changed without replacing the microcomputer and the nonvolatile memory at the same time. If you replace it with a non-volatile memory that stores both versions of the correction data before it is changed, the correct correction data will be used only for the correct version of the microcomputer, so the versions will differ during manufacturing. There is no need to worry that suitable correction data will not be entered.

Further, since the correction data must be paired with the program, it is not necessary to prepare the same number of non-volatile memories as the created version, and if a new version of the correction data is created, all If the corrected data of the versions are sequentially stored in the non-volatile memory, all the versions can be finally covered by one non-volatile memory, and the trouble is eliminated.

[Brief description of drawings]

FIG. 1 is a flowchart showing an operation of a CPU in a preferred embodiment of a control device with a program ROM correction function and an electronic device having the control device according to the present invention.

FIG. 2 is a block diagram showing a preferred embodiment of the electronic device of the present invention.

FIG. 3 is a diagram schematically showing the contents of a nonvolatile memory used in a control device with a program ROM correction function of the present invention and an electronic device having the control device.

FIG. 4 CP in a conventional control device or electronic device
6 is a flowchart showing the operation of U.

5 is a diagram schematically showing the contents of a non-volatile memory used in the conventional device of FIG.

[Explanation of symbols]

10 Microcomputer 12 CPU (means for reading ID number, means for judging, means for permitting) 14 RAM 16 ROM (program ROM) 18 Interface 20 Electronic equipment 22 Controlled equipment 24 Nonvolatile memory

Claims (3)

[Claims] 1. A CPU, a program ROM storing the operation procedure of the CPU, and data for correcting the ID number of the CPU and the contents of the program ROM corresponding to the version of the program ROM. A non-volatile memory, means for reading the ID number stored in the non-volatile memory, means for determining whether the read ID number is equal to the ID number written in the program ROM, and its determination As a result, in a program ROM correction function control device having means for permitting reading of correction data corresponding to a program from the non-volatile memory only when the ID numbers are the same, one ID is previously stored in the non-volatile memory. 1 corresponding to the number
If two predetermined addresses are written and the ID numbers are not equal as a result of determining the ID numbers, another ID number is read from the address stored together with the ID number stored in the nonvolatile memory, and the ID number is read again. A means for determining whether or not the numbers are the same, and a means for permitting reading of the correction data corresponding to the program from the nonvolatile memory only when the results of the determination indicate that the ID numbers are the same. A control device with a program ROM correction function. 2. An electronic device having a controlled device, comprising:
A CPU, a program ROM storing the operation procedure of the CPU, and a nonvolatile memory corresponding to the version of the program ROM and in which data for correcting the ID number of the CPU and the contents of the program ROM are written , Means for reading the ID number stored in the non-volatile memory, means for determining whether the read ID number is equal to the ID number written in the program ROM, and the result of the determination, the ID number An electronic device configured such that the control target device is controlled by a control device with a program ROM correction function, which has a means for permitting the correction data corresponding to the program to be read from the non-volatile memory only when the two are equal. In the non-volatile memory, 1 corresponding to one ID number in advance
If two predetermined addresses are written and the ID numbers are judged to be unequal to each other, another ID number is read from the address stored together with the ID number stored in the nonvolatile memory, and the ID number is read again. A means for determining whether or not the numbers are the same, and a means for permitting reading of the correction data corresponding to the program from the nonvolatile memory only when the results of the determination indicate that the ID numbers are the same. And an electronic device having a control device with a program ROM correction function. 3. A CPU, a program ROM that stores the operating procedure of the CPU, and a non-volatile memory connection portion to which a non-volatile memory in which the correction data of the program of the program ROM is written is detachably mountable. In the method of correcting a program in the program ROM of a microcomputer having: a plurality of correction versions of correction data are written in advance in the nonvolatile memory, and one I version is provided for each correction version.
When the program of the program ROM is corrected by writing it together with a D number, the step of mounting the non-volatile memory in the non-volatile memory connection part, and storing the non-volatile memory in the non-volatile memory The read ID number, a step of determining whether the read ID number is equal to the ID number written in the program ROM, and the result of the determination is that the ID numbers are equal to each other, the nonvolatile memory From the step of permitting the reading of the correction data corresponding to the program from the step of, and if the result of judging the ID numbers is not the same, the address stored together with the ID number stored in the non-volatile memory is used. A step of reading out another ID number and determining again whether the ID numbers are the same, Constant results, program correcting method characterized by a step of permitting to read the correction data corresponding to the program from the nonvolatile memory only if the ID number comrades are equal.