JP2022161197A - Vehicle computer device - Google Patents

Abstract

To provide a vehicle computer device which can quickly update existing data stored in a nonvolatile memory.SOLUTION: In a vehicle computer device, a storage area 131 includes: a first storage area M11 storing first data D1b; a second storage area M12 storing second data D2; and margin areas E11, E12 which are arranged between the first storage area and the second storage area, and in which new data are written. An arithmetic device acquires a differential dataset which includes one or more pieces of differential data indicating a difference between before and after the update of the first data, and when a data size of the first data after the update is larger than a data size of the first data before the update, and the increase amount of the data size is smaller than the capacity of the margin area, writes at least one differential data in the differential dataset into the margin area.SELECTED DRAWING: Figure 7

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle computer device having a non-volatile memory and a function of updating existing data stored in the non-volatile memory.

2. Description of the Related Art Conventionally, a vehicle computer device (hereinafter referred to as a "conventional device") for controlling a vehicle is known (see, for example, Patent Literature 1 below). Conventional devices include non-volatile memory (flash ROM). Data (eg, binary data representing a plurality of computer programs) used to control the vehicle is stored in the non-volatile memory.

For example, when improving the function of a vehicle, an operator creates new binary data (hereinafter referred to as "old ROM image data IMa") that is different from the current binary data (hereinafter referred to as "old ROM image data IMa"), as shown in FIG. , referred to as "new ROM image data IMb"). Then, the operator creates difference data representing the difference between the old ROM image data IMa and the new ROM image data IMb. Specifically, the old ROM image data IMa and the new ROM image data IMb are respectively read into work areas WSa and WSb secured in the SDRAM of the development computer. Then, the work areas WSa and WSb are divided into blocks W[1], W[2], . As shown in FIG. 11, when the content (bit pattern) of block W[n] of old ROM image data IMa and the content (bit pattern) of block W[n] of new ROM image data IMb are different, the corresponding Block W[n] of new ROM image data IMb is extracted as difference data DD[n]. A differential data set DS consisting of one or more differential data DD[n] thus extracted is transferred to the conventional device.

10 to 12 (and FIGS. 2 to 5 and 7 to 9, which will be described later), rectangles in each block represent a logical address space generally called a "page". As shown in FIG. 12, the arrowhead side of the arrow corresponds to the lower (head) address side of the old ROM image data IMa and the new ROM image data IMb, and the arrowhead side corresponds to the upper (end) address side. The color (shading) of each rectangle (page) corresponds to the content of each page (data (bit pattern) stored in each page).

A conventional device acquires a difference data set DS via a communication line or a storage medium (for example, an SD card), and based on the difference data DD[n] and the old ROM image data IMa included in the difference data set DS, The new ROM image data IMb is generated (restored), and the generated new ROM image data IMb is written in the nonvolatile memory.

Japanese Patent No. 6568947

Here, as shown in FIG. 10, the old ROM image data IMa is formed by concatenating a plurality of binary data (first data D1, second data D2, . . . ) respectively representing a plurality of programs. There may be In this case, it may be necessary to update only some of the programs, and not to update the other programs. For example, when only the first data D1 is updated, new data ND may be inserted in the middle portion (for example, block B[3]) of the first data D1. In other words, in this case, the new ROM image data IMb shifts the contents of each page on the upper address side from the page Pb of the block B[3] of the old ROM image data IMa by two pages to the upper address side. It is the same as the data in which the new data ND is stored in the page Pb.

In this example, the second data D2, the third data D3, . However, in the new ROM image data IMb, the logical address of the area where the second data D2, third data D3, . It is shifted to the upper address side with respect to the address.

That is, the contents (bit patterns) of blocks B[1] and B[2] of the new ROM image data are the same as those of blocks B[1] and B[2] of the old ROM image data. On the other hand, the contents of the blocks after block B[3] of the new ROM image data are different from the contents of the blocks after block B[3] of the old ROM image data. Therefore, the contents of each block after block B[3] of the new ROM image data are extracted as differential data DD[3], DD"4", . Thus, in the conventional device, the difference data set DS includes the difference data DD[n] that constitute the second data D2, the third data, .

If the block into which the new data ND is inserted is the first block B[1], all the new ROM image data are extracted as the differential data DD[n]. Thus, in the conventional device, the data size of the differential data set DS may become relatively large, and in this case, it takes a relatively long time to cause the vehicle computer device to acquire the differential data set DS.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a vehicle computer system capable of rapidly updating existing data stored in a non-volatile memory.

In order to solve the above problems, the vehicle computer device (1) of the present invention comprises:
a nonvolatile memory having a rewritable storage area (131) and storing first data (D1, PD11) and second data (D2, PD12) in the storage area;
an arithmetic device (11) for controlling a vehicle (V) using the first data and the second data, the arithmetic device having a function of updating the first data;
Prepare.
The storage area is
a first storage area (M1, M!1) storing the first data;
a second storage area (M2, M12) storing the second data;
blank areas (E1, E11) provided between the first storage area and the second storage area and capable of writing new data;
including.
The computing device acquires a difference data set (DS) including one or more difference data (DD[n]) representing a difference between before and after the update of the first data, and data of the first data before update. When the data size of the first data after update is larger than the size and the increase is smaller than the capacity of the margin area, at least one difference data in the difference data set is moved to the margin. configured to write to the region.

Of the existing first data and second data stored in the nonvolatile memory, there are cases where the first data needs to be updated and the second data does not need to be updated. In this case, the data size of the first data after update (hereinafter referred to as "new data") is compared to the data size of the first data before update (hereinafter referred to as "old data"). can be large. In the vehicle computer device according to the present invention, a blank area is provided between the first storage area and the second storage area in the storage area of the nonvolatile memory. Therefore, even if the data size of the new data is slightly larger than the data size of the old data, the increased amount can be written in the blank area. That is, only the first data to be updated can be updated without affecting the second storage area storing the second data other than the first data to be updated. That is, the difference data set corresponds to part (or all) of the new data and does not include the second data that is not subject to update. Therefore, the data size of the difference data set is smaller than that of the conventional apparatus (when no margin area is provided). Therefore, the time required for the vehicle computer to acquire the difference data set DS is short, and the existing data stored in the nonvolatile memory can be quickly updated.

FIG. 1 is a block diagram of a vehicle computer device according to one embodiment of the present invention. FIG. 2 is a memory map of the flash ROM shown in FIG. FIG. 3 is a memory map of old ROM image data. FIG. 4 is a memory map of new ROM image data. FIG. 5 is a memory map of the difference data set. FIG. 6 is a flow chart of the update processing program. FIG. 7 is a memory map of the flash ROM of the vehicle computer device according to the modification of the present invention. FIG. 8 is a memory map showing new ROM image data according to the modification shown in FIG. FIG. 9 is a memory map of the difference data set according to the modification shown in FIG. FIG. 10 is a memory map of old ROM image data and new ROM image data of a conventional vehicle computer device. FIG. 11 is a memory map of differential data sets according to the conventional device shown in FIG. FIG. 12 is a diagram showing the arrangement of blocks and pages (in the direction from lower logical addresses to higher logical addresses) that make up the storage area of the flash ROM.

(Constitution)
A vehicle computer device 1 according to one embodiment of the present invention shown in FIG. A CPU, SDRAM 12, flash ROM 13, memory controller 14, and communication device 15 are mounted on a printed wiring board.

The CPU executes various computer programs (hereinafter simply referred to as "programs"), which will be described later, to control the engine, brakes, etc. of the vehicle V. FIG. The SDRAM 12 is a volatile memory that temporarily stores programs and calculation results in the course of their execution.

The flash ROM 13 is a NAND nonvolatile memory. The flash ROM 13 has a rewritable area 131 and a rewritable area 132 as shown in FIG. The rewritable area 132 is arranged on the upper address side with respect to the rewritable area 131 . A program (binary data) stored in the rewritable area 131 can be updated (OTA). On the other hand, the program (binary data) stored in the rewrite prohibited area 132 is not updated in principle (except during the production process of the vehicle computer device 1).

Programs for controlling the engine, brakes, etc. (for example, AEB (autonomous (Emergency Breaking) program, ACC (Adaptive Cruise Control) program, LKAS (Lane Keeping Assist System) program, etc.) is stored (stored).

The rewritable area 131 (logical address space) is divided into a plurality of blocks B (for example, block B[1] to block B[256]) each having a predetermined size (storage capacity). Furthermore, each block B is divided into a plurality of pages P of a predetermined size. As described above, the NAND flash ROM 13 is used in this embodiment. Therefore, if data has already been written to a page P in the block B, the page P cannot be overwritten (directly rewritten) with new data. Therefore, first, the contents of all pages of the block B excluding the page P are backed up in the SDRAM 12 . Next, all data in the block B are erased. Finally, new data is written to the page P of the block B, and the data backed up in the SDRAM 12 is written back to the block B.

At the time when the vehicle V is shipped from the factory, for example, as shown in FIG. remembered. Further, the second data D2 representing the ACC program is stored in the second storage area M2 consisting of blocks B[9] to B[13]. In addition, the third data D3 representing the LKAS program is stored in the third storage area M3 consisting of blocks B[17] to B[21]. Fourth data, fifth data, . . . representing a plurality of other programs are stored in fourth storage areas, fifth storage areas, .

The data in blocks B[6] to B[8] between the first memory area M1 and the second memory area M2 has been erased, and new data can be written to the page P in this area. Hereinafter, this area will be referred to as a first blank area E1. The area between the second storage area M2 and the third storage area M3 is also a second blank area E2 similar to the first blank area E1. In this way, the blank area E (the first blank area E1, the second blank area E2, and the third blank area) consists of three blocks B that are continuous at the end of the area in which the binary data representing each program is stored. E3, . . . ).

Further, version information (version number va (eg, “1.00”)) indicating the version of the current ROM image data is stored in a predetermined block B (eg, block B [256]) in the latter half of the rewritable area 131. remembered.

Binary data representing a boot program, an update processing program, and the like are stored in the rewrite prohibited area 132 . The boot program includes steps (instructions) for initializing the CPU, SDRAM 12, memory controller 14 and communication device 15 when the vehicle V is started. The update processing program includes steps (instructions) for updating various programs stored in the rewritable area 131 .

The ROM image data representing the contents of the rewritable area 131 and the rewritable area 132 (factory version) are written in the flash ROM 13 using a ROM writer in the manufacturing process of the vehicle computer device 1. . Then, the flash ROM 13 is mounted on a printed wiring board.

Referring to FIG. 1 again, the memory controller 14 converts logical addresses to physical addresses when transmitting and receiving data between the CPU and the flash ROM 13 and between the SDRAM 12 and the flash ROM 13 . Furthermore, the memory controller 14 identifies normal blocks and defective blocks of the flash ROM 13 . For example, if the block (logical address space) specified as the data write destination is a defective block, the memory controller 14 writes the data to a normal block (physical address space) different from the specified block. Furthermore, the memory controller 14 equalizes (wear leveling) the number of rewrites of each block in the physical address space of the flash ROM 13 . The processing executed by the memory controller 14 may be executed by the CPU.

As will be described later in detail, the communication device 15 receives data for updating the program (difference data set DS described later) from the distribution server SV via a wireless communication line, and supplies the data to the CPU.

(motion)
When the engine of the vehicle V is started, the CPU executes the boot program and copies binary data representing each program stored in the flash ROM 13 to predetermined storage areas of the SDRAM 12 . The CPU controls the vehicle V by executing a program represented by the binary data copied to the SDRAM 12 .

By the way, for example, in order to improve the function of the vehicle V, it may be necessary to update the program (binary data) stored in the rewritable area 131 . A procedure for updating the AEB program (first data D1) will be described below as an example. In this case, first, the worker modifies the source code of the AEB program using the development computer PC. Then, the operator compiles the modified source code to generate an object file, links the object file with another object file, and generates binary data representing a new AEB program. Hereinafter, the binary data representing the AEB program before update will be referred to as "old first data D1a", and the binary data representing the AEB program after update will be referred to as "new first data D1b" (see FIGS. 3 and 4). reference).

In this example, the new first data D1b is the same as "data obtained by inserting new data ND into the middle portion of the old first data D1a". The data size of the new data ND is the same as the storage capacity of two pages P. That is, the data size of the new first data D1b is larger than the data size of the old first data D1a.

Next, the worker secures two work areas WSa and WSb in the logical address space of the SDRAM of the development computer PC. The storage capacity of the work area WSa is the same as that of the rewritable area 131 . The storage capacity of the work area WSb is also the same as that of the rewritable area 131 .

Next, the operator stores the same data as the pre-update binary data (hereinafter referred to as "old ROM image data IMa") stored in the rewritable area 131 in the work areas WSa and WSb. let it load. That is, the rewritable area 131 before update is reproduced in the work area WSa and the work area WSb. In the following description, among work areas WSa and WSb, areas corresponding to blocks B[1] to block B[256] are referred to as blocks W[1] to W[256].

Next, the worker replaces the old first data D1a stored in the work area WSb with the new first data D1b. At this time, the new first data D1b is written in the work area WSb so that the leading address of the old first data D1a and the leading address of the new first data D1b match. As described above, the data size of the new first data D1b is larger than the data size of the old first data D1a. That is, the old first data D1a is stored in an area consisting of five blocks W (block W[1] to block W[5]), while the new first data D1b is stored in an area consisting of six blocks W (block W[1] to block W[5]). It is stored in an area consisting of blocks W[1] to W[6]). Here, block W[6] corresponds to block B[6], which is the top block of the first blank area E1. In the work area WSb, the second data D2, the third data D3, . Binary data is retained as it is without being rewritten.

Further, the worker updates the version information (version number va) stored in block W[256]. Specifically, the operator updates the version number va to the version number vb obtained by adding a predetermined step value dv (for example, "0.01") to the version number va. The data generated in the work area WSb as described above is called "new ROM image data IMb".

Next, the operator causes the development computer PC to execute a difference data extraction program for extracting the difference data DD[n]. The development computer PC compares the contents of block W[n] in work area WSa with the contents of block W[n] in work area WSb. Then, when the contents of block W[n] in work area WSa and the contents of block W[n] in work area WSb are different, computer PC for development converts the contents of block W[n] in work area WSb to the difference. Extract as data DD[n]. In the examples shown in FIGS. 3 and 4, the contents of blocks W[3] to W[6] and block W[256] in the work area WSb are differential data DD[3] to differential data DD[6], respectively. ], and differential data DD[256] (see FIG. 5). Next, the worker uploads the extracted difference data DD[n] to the distribution server SV as one difference data set DS (see FIG. 1). At that time, a name including the vehicle model name of the application target and the version number vb of the new ROM image data IMb is given as the file name of the differential data set DS. As a result, the difference data set DS can be distributed (OTA) to each vehicle V from the distribution server SV via the wireless communication line.

The CPU of the vehicle computer device 1 executes the update processing program shown in FIG. 6 at predetermined time intervals. The CPU starts the update processing program from step 600 . Next, at step 601, the CPU determines whether or not the ROM image data stored in the rewritable area 131 needs to be updated. Specifically, the CPU accesses the distribution server SV via the communication device 15 and determines whether or not the difference data set DS that satisfies the following conditions has been uploaded to the distribution server SV.
<Condition>
- The file name contains the model name of the own vehicle.
- The version number vb included in the file name is greater than the version number va of the current ROM image data stored in block B[256], and the difference between the two matches the step value dv.
If the difference data set DS that satisfies the above <condition> has been uploaded, the CPU determines that "the ROM image data stored in the rewritable area 131 needs to be updated" (601: Yes). , go to step 602 .

Next, in step 602, the CPU downloads the difference data set DS (see FIG. 5) that satisfies the above <conditions> from the distribution server SV via the communication device 15. FIG. Next, in step 603, the CPU erases blocks in which data has already been written, among the blocks B[n] corresponding to the difference data DD[n] included in the downloaded difference data set DS. Next, in step 604, the CPU writes difference data DD[n] to block B[n].

The differential data set DS shown in FIG. 5 includes differential data DD[3] to differential data [6] and differential data DD[256]. Referring now to FIG. 2, data has already been written to blocks B[3] to B[5] and block B[256]. Therefore, the CPU erases blocks B[3] to B[5] and block B[256]. Then, the CPU writes the difference data DD[3] to DD[6] and the difference data DD[256] to the blocks B[3] to B[6] and the block B[256], respectively.

After finishing writing all the difference data DD[n], the CPU ends the update processing program in step 605 .

In step 601 above, if the difference data set DS that satisfies the above <condition> has not been uploaded, the CPU states that "there is no need to update the ROM image data stored in the rewritable area 131" (601 : No) and proceeds to step 605 .

For example, when a relatively large modification is made to the AEB program, when each block of the old first data D1a and each block of the new first data D1b are compared, there are blocks whose contents match each other. may not. In this case, all blocks of the new first data D1b are included in the differential data set DS.

As described above, when updating a program among the existing programs stored in the rewritable area 131, binary data representing the updated program (hereinafter referred to as "new data") data The size may be larger than the data size of the binary data representing the program before update (hereinafter referred to as "old data"). In this embodiment, in the rewritable area 131 of the flash ROM 13, a continuous blank area is provided at the end of the binary data storage area of each program. Therefore, even if the data size of the new data is slightly larger than the data size of the old data, the increased amount can be written in the blank area. That is, only the target program can be updated without affecting the storage area of the binary data representing programs other than the program to be updated. In other words, the difference data set DS corresponds to part (or all) of the new data and does not contain binary data representing programs not to be updated. Therefore, the data size of the difference data set DS is smaller than that of the conventional apparatus (where the blank area is not provided). Therefore, the time required for the vehicle computer device 1 to download the difference data set DS is short, and the existing data stored in the flash ROM 13 can be quickly updated.

The present invention is not limited to the above embodiments, and various modifications can be adopted within the scope of the present invention as described below.

<Modification 1>
In the above embodiment, the first data D1, the second data D2, the third data D3, . are stored in M3, . . . , and blank areas are provided between these storage areas. Instead, as shown in FIG. 7, the first data D1, the second data D2, the third data D3, . , ``PD31 to PD34'', . . . ), and blank areas E11, E12, . may According to this, as shown in FIG. 8, for example, when the data size of the parts data PD11 increases due to the update of the AEB program (first data D1), the increased amount is transferred to the subsequent blank area E11. can be written to That is, only the parts data PD11 can be updated without affecting the storage areas of the other parts data PD. 2 to 5, in the new first data D1b, a plurality of blocks from the block in which the new data ND is inserted to the last block of the new first data D1b are the difference data DD. extracted as [n]. On the other hand, in this modification, only the block in which the new data ND is inserted and the block immediately after that are extracted as the difference data DD[n] from the new first data D1b. Therefore, according to this modification, the data size of the difference data set DS can be further reduced, and the existing data stored in the flash ROM 13 can be updated more quickly.

<Modification 2>
2, each blank area E is composed of three blocks B, and each blank area E is composed of one block B in the example illustrated in FIG. The number of blocks B forming the blank area E (capacity of the blank area E) is not limited to the above example. The capacity of each blank area E may not be the same. For example, it is preferable to allocate a relatively large-capacity blank area E to a storage area for data that is highly likely to be significantly modified.

<Modification 3>
In the above embodiment, the NAND type flash ROM 13 is used, but instead of this, a NOR type flash ROM or EEPROM may be used.

<Modification 4>
In the above embodiment, the boot program, the update processing program, and the like are stored in the rewrite prohibited area 132 of the flash ROM 13, but these programs are stored in a nonvolatile memory (eg, EEPROM, MASKROM, etc.) provided separately from the flash ROM 13. etc.).

DESCRIPTION OF SYMBOLS 1... Computer apparatus for vehicles, 13... Flash ROM, 15... Communication apparatus, B, W... Block, D1... 1st data, D2... 2nd data, D3... 3rd data, DD... Difference data, DS... Difference data set, E...blank area, IMa...old ROM image data, IMb...new ROM image data, PD...parts data, SV...distribution server, V...vehicle

Claims (1)

a nonvolatile memory having a rewritable storage area and storing first data and second data in the storage area;
an arithmetic device for controlling a vehicle using the first data and the second data, the arithmetic device having a function of updating the first data;
A vehicle computer device comprising:
The storage area is
a first storage area storing the first data;
a second storage area storing the second data;
a blank area provided between the first storage area and the second storage area, in which new data can be written;
including
The computing device acquires a difference data set including one or more pieces of difference data representing a difference between before and after the update of the first data, and compares the data size of the first data before update with the data size of the after update. When the data size of the first data is large and the increase is smaller than the capacity of the blank area, at least one differential data of the differential data set is written to the blank area.
Vehicle computer equipment.

Images