JP6984201B2 - Electronic control device - Google Patents

Description

The present invention relates to an electronic control device.

For example, CAN (Controller Area Network: registered trademark) is an in-vehicle network used for various parts such as a power train system and a body system in an automobile, and can communicate with each other by connecting a plurality of electronic control devices by bus. (For example, see Patent Document 1). This Patent Document 1 describes the basic processing of the CAN communication method, and in particular, it is possible to synchronize data communication between specific nodes among a plurality of nodes.

Japanese Unexamined Patent Publication No. 2003-264567

As described in Patent Document 1, when CAN communication processing is applied, an empty area may be created in the CAN data frame. In recent years, the amount of data to be transmitted and received between a plurality of nodes tends to increase, and the bus load is becoming high. Therefore, it is desired to construct a communication system capable of reducing the bus load.

An object of the present invention is to provide an electronic control device constituting a communication system capable of reducing a bus load.

The invention according to claim 1 is a communication system in which a transmitting node stores first data in a transmission frame in a predetermined format and transmits the first data to a network, and a receiving node receives the first data as a receiving frame through the network. It is targeted. The electronic control device constituting the transmission node according to claim 1 is assigned by an allocation unit and an allocation unit that divides and allocates other second data to an empty area excluding the area in which the first data is allocated to the transmission frame. A transmission unit for transmitting the divided data and the first data as a transmission frame is provided.

Since the allocation unit divides and allocates the other second data to the empty area excluding the area to which the first data is allocated, the empty area in the area of the predetermined format can be utilized. Therefore, the empty area can be effectively used. It is not necessary to separately transmit the second data as a transmission frame, and the bus load can be reduced.

Further, according to the invention of claim 2, the identification unit discriminates between the first data and the divided data of the second data from the received frames, and restores data from the divided data based on the allocation destination information. Generate. This allows the data to be restored.

Configuration example of the communication system in the first embodiment Electrical configuration diagram of electronic control device A diagram functionally showing the electrical configuration of an electronic control device that serves as a transmitting node. A diagram functionally showing the electrical configuration of an electronic control device that serves as a receiving node. The figure which shows a part of the communication data format of the data frame used for CAN. Diagram showing the contents of the management table Other data examples Flowchart that outlines the processing of the sending node Flowchart that outlines the processing of the receiving node A diagram schematically showing an image of transmission / reception processing Diagram showing the result of data restoration Other data examples in the second embodiment A diagram schematically showing an image of transmission / reception processing Diagram showing the result of data restoration The figure which shows the content of the management table in 3rd Embodiment Other data examples Flowchart that outlines the processing of the sending node Flowchart that outlines the processing of the receiving node A diagram schematically showing an image of transmission / reception processing Diagram showing the result of data restoration Other data examples Diagram showing the contents of the management table Flowchart that outlines the processing of the sending node Flowchart that outlines the processing of the receiving node A diagram schematically showing an image of transmission / reception processing Diagram showing the result of data restoration

1 to 10 show explanatory views of the first embodiment. FIG. 1 shows a configuration example of the communication system 1. For the in-vehicle network (hereinafter abbreviated as network) 2, for example, a protocol of CAN (Controller Area Network: registered trademark) is adopted. CAN is a closed in-vehicle network that employs a communication protocol used for data transmission between interconnected devices. Various electronic control units (ECUs: Electronic Control Units), that is, ECU_A3, ECU_B4, and ECU_C5 (hereinafter abbreviated as ECUs 3, 4, and 5) are connected to this network 2. These ECUs 3 to 5 are connected to the network 2 and can communicate with each other. Many of these ECUs 3 to 5 perform various controls in the vehicle by operating in cooperation with other ECUs. Since it is assumed that a malicious third party illegally connects a device to the network 2, the unauthorized device 6 is shown in FIG. 1 using a broken line.

As shown in FIG. 2, the ECUs 3 to 5 include a microcomputer (hereinafter referred to as a microcomputer) 10 having a CPU 7, ROM 8, RAM 9, and other memories (for example, backup RAM, EEPROM, etc .: not shown), and a communication controller 11 by CAN. , Equipped with. Hereinafter, the ROM 8, RAM 9, and other memories (for example, backup RAM and EEPROM) will be collectively referred to as memories. The communication controller 11 makes a communication connection with the network 2 by, for example, CAN. The microcomputer 10 of the ECU (for example, 3) is connected to the communication controller 11 and is connected for communication with another ECU (for example, 4 or 5) connected to the network 2.

FIG. 3A functionally illustrates the case where the ECU 3 is considered as a transmission node. The CPU 7 has functions as a transmission unit 12 and an allocation unit 13 by executing a program stored in the memory, and has a storage area of a CAN format management table 14 in the memory. Further, FIG. 3B functionally illustrates the case where the ECU 4 is considered as a receiving node, and the CPU 7 serves as the identification unit 19 and the restoration unit 20 by executing a program stored in the memory. It has a function and has a storage area of a CAN format management table 14 in the memory.

FIG. 4 shows the format of the data frame used for CAN. The data frame 15 is divided into a format area including an arbitration field 16 and a data field 17 for storing data. For example, the data frame 15 also includes other fields, but the description thereof is omitted.

The arbitration field 16 is a field indicating the type and priority of data, and is usually a field for storing an 11-bit ID (corresponding to an identification number: so-called CANID). The data field 17 is a field for storing data to be actually transmitted and received, and is substantially defined by a maximum of 64 bits in 8-bit units depending on the DLC setting. As described above, the data is CANID, that is, data to be transmitted / received for each identification number, and the data field 17 is capable of transmitting data in 8-bit units.

Further, in the CAN protocol, the internal bit information of the data frame 15 is determined for each CANID. Therefore, as shown in FIG. 5, the CAN management table 14 is prepared in each of the ECUs 3 to 5. The example shown in FIG. 5 will be described. When the CANID is 101, the upper 4 bits in 1 byte are defined as used bits, that is, a used area, and are defined as a storage area for the original CANID 101 data (corresponding to the first data). When the CANID is 101, the lower 4 bits are defined as empty bits, that is, empty areas.

When the CANID is 102, it is shown that the upper 6 bits in 1 byte are defined as the data storage area of the original CANID 102 as the used bits, but the lower 2 bits are defined as the empty bits. Further, when the CANID is 103, the upper 2 bits and the lower 3 bits in 1 byte are defined as used bits as the data storage area of the original CANID 103, but the middle 3 bits are defined as free bits. Shows. Hereinafter, the frames to which the CANIDs 101 to 103 are assigned will be referred to as frames 101 to 103 and will be described below.

The present embodiment is characterized in that other data (corresponding to the second data) α is set as a free bit, that is, a free bit in frames 101 to 103. FIG. 6 shows an example of other data α. The other data α shows an example prepared in, for example, 9 bits, but the amount of information is not limited to this. In the following, the 9-bit data α to be transmitted as the data frame 104 using the prior art is set by the microcomputer 10 of the ECU 3 as an empty bit of frames 101 to 103, and the microcomputer 10 of the ECU 4 is set as this empty bit. The form of the process for restoring the data α is shown.

In the management table 14 shown in FIG. 5, bits α8 to α0 of other data α are assigned to the empty bits of each frame 101 to 103, respectively. For example, when the CANID is 101, the upper 4 bits α8 to α5 of the data α are assigned to the empty bits of the lower 4 bits. When the CANID is 102, the middle 2 bits α4 to α3 of the data α are assigned to the lower 2 empty bits. Further, when the CANID is 103, the lower 3 bits α2 to α0 of the data α are assigned to the empty bits of the middle 3 bits. Each of the ECUs 3 to 5 holds the management table 14 of the CAN, thereby establishing the communication rule of the network 2.

In the following description, the transmitting side ECU 3 will be used as a data frame transmitting node, and the receiving side ECU 4 will be used as a data frame receiving node. FIG. 7 shows the transmission process of the transmitting side ECU 3, that is, the transmitting node, and FIG. 8 shows the receiving process of the receiving side ECU 4, that is, the receiving node.

As shown in FIG. 7, the microcomputer 10 of the ECU 3 creates frames 101 to 103 in T1. Here, the microcomputer 10 refers to the management table 14, and creates frames 101 to 103 by setting data in each bit of the frames 101 to 103 defined as “used” in the management table 14.

After that, the microcomputer 10 of the ECU 3 determines whether or not the update cycle time of the frame 104 has elapsed in T2. Then, the microcomputer 10 of the ECU 3 determines NO in T2 if the update cycle time has not elapsed, counts up the update cycle counter in T3, and transmits frames 101 to 103 in T4.

When the update cycle time of the frame 104 elapses in T2, the microcomputer 10 of the ECU 3 determines YES in T2, and updates the data in the frame 104 in T5. At this time, another 9-bit data α is obtained as the frame 104 shown in FIG. After that, the microcomputer 10 of the ECU 3 refers to the management table 14, and sets data in each bit defined as an empty bit in the management table 14 in T6 to T8. For example, the microcomputer 10 of the ECU 3 sets the upper 4 bits of the frame 104 to the empty 4 bits of the frame 101 in T6. Further, for example, the microcomputer 10 of the ECU 3 sets the middle 2 bits of the frame 104 to the empty 2 bits of the frame 102 in T7.

Further, for example, the microcomputer 10 of the ECU 3 sets the lower 3 bits of the frame 104 to the empty 3 bits of the frame 103 in T8. Then, the microcomputer 10 of the ECU 3 clears the update cycle counter of the frame 104 at T9. Then, the microcomputer 10 of the ECU 3 transmits the frames 101 to 103 by outputting the frames 101 to 103 to the network 2 in T4. As a result, other data α can be transmitted without outputting the other data α to the network 2 as a frame 104.

On the other hand, as shown in FIG. 8, the microcomputer 10 of the ECU 4 serving as a receiving node waits for reception of frames 101 to 103 from the network 2 in R1 to R3. When the microcomputer 10 of the ECU 4 receives the frame 101, it is determined as YES in R1, the management table 14 is referred to, the used bit in the frame 101 is accepted as the data of the CANID 101 in the R4a, and the lower part of the data field of the frame 101 in the R4b. 4 bits, that is, bits 3 to bit0 are set as the upper 4 bits of the storage area of the restored data αZ. Thereby, the original data of CANID 101 and the divided data α8 to α5 of other data α can be distinguished from the received frame 101. Then, the microcomputer 10 of the ECU 4 sets a flag that the frame 101 has been received in R5.

Further, when the microcomputer 10 receives the frame 102, it is determined as YES in R2, the management table 14 is referred to, the used bit in the frame 102 is accepted as the data of the CANID 102 in the R6a, and the lower 2 of the data field of the frame 102 in the R6b. Bits, that is, bits bit1 and bit0, are set to the middle 2 bits of the storage area of the restored data αZ. Thereby, the original data of CANID 102 and the divided data α4 and α3 of the other data α can be distinguished from the received frame 102. Then, the microcomputer 10 of the ECU 4 sets a flag that the frame 102 has been received in R7.

Further, when the microcomputer 10 receives the frame 103, it is determined as YES in R3, the management table 14 is referred to, the bits used in the frame 103 are accepted as the original CANID 103 data in R8a, and the data field of the frame 103 is received in R8b. The middle 3 bits, that is, bits 5 to 3, are set in the lower 3 bits of the storage area of the restored data αZ. Thereby, the original data of the CANID 103 and the divided data α2 to α0 of the other data α can be distinguished from the received frame 103. After processing R8a and R8b, the microcomputer 10 of the ECU 4 determines whether or not all the frames 101 to 102 have been received in R9, and only when all the frames 101 to 102 have been received. , R10 creates the restored data αZ.

In R9, if the microcomputer 10 of the ECU 4 has not received all the frames 101 to 102, it is determined as NO in R9, and when the frames 101 to 103 are further waited and the frames 103 are received again in R3, the frames 101 to 101 It is determined whether or not all 102 have been received, and when all the frames 101 to 102 have been received, the restored data αZ is created in R10.

The microcomputer 10 of the ECU 4 combines the upper 4 bits received in the frame 101, the middle 2 bits received in the frame 102, and the lower 3 bits received in the frame 103 in the R10 to create the restored data αZ. Then, the microcomputer 10 of the ECU 4 eliminates the received data of the frames 101 to 102, and at this time, clears the flag set as received by R5 and R7. As a result, the restored data αZ can be generated.

FIG. 9 shows an image of transmission / reception processing. As shown in FIG. 9, the ECU 3 outputs the frames 101 to 103 as transmission frames to the network 2, and the ECU 4 receives all the frames 101 to 103 as reception frames. As described above, each free bit in frames 101 to 103 is predetermined in the management table 14 so as to correspond to each bit in the data α. Therefore, the microcomputer 10 of the ECU 3 on the transmitting side can grasp which free bit each bit data α8 to α0 of the other data α should be inserted by referring to the management table 14, and the ECU 4 on the receiving side The microcomputer 10 can determine which free bit each bit data α8 to α0 of the other data α is inserted by referring to the management table 14, and can generate the restored data αZ as shown in FIG. .. As a result, it is not necessary to output the data α to the network 2 as another frame 104, so that the bus load can be reduced.

Further, for example, as shown in FIG. 1, it is assumed that the unauthorized device 6 is connected to the network 2. The fraudulent device 6 is a device illegally connected by a malicious third party or the like. When the unauthorized device 6 is connected to the network 2, the data frame flowing through the network 2 can be read. However, even if the unauthorized device 6 receives the data frame, it becomes difficult to determine which bit in the data field is the true data. Even if the unauthorized device 6 reads the data field of the frame 101, for example, it contains the divided data α8 to α5 to be combined and read together with the data of the frame 101, so that these data should be regarded as the original data. Can be directed to. As a result, the unauthorized device 6 recognizes the divided data α8 to α5 of the other data α as a part of the data of the frame 101, so that the possibility of misidentifying the data length of the data can be increased. The same applies to the other frames 102 and 103.

Hereinafter, the features of this embodiment are conceptually summarized. The microcomputer 10 of the ECU 3 divides and allocates other data α to the empty bits excluding the area where the original data is allocated to the transmission frames 101 to 103, and allocates the original data and the assigned divided data α8 to α5 and α4 to α3. , Α2 to α0 are transmitted as transmission frames 101 to 103, respectively. As a result, since the free bits in the transmission frames 101 to 103 of the predetermined format can be utilized, the communication information amount of the network 2 does not increase particularly, and the bus load can be reduced. It is possible to prevent an increase in the communication volume of the network 2.

Further, for example, even if the unauthorized device 6 is connected to the network 2 and the data flowing through the network 2 is read, the data of one transmission frame (for example, 101) and a part of the data α of the other frame 104 are part of the data α. Since the divided data α8 to α5 are read, it becomes difficult to analyze which data is normal data, and the data cannot be easily analyzed.

On the other hand, the microcomputer 10 of the ECU 4 on the receiving side discriminates between the original data and the divided data α8 to α5, α4 to α3, and α2 to α0 of the original data and the other data α from the received frames 101 to 103, and the divided data α8. Restored data αZ is generated from ~ α5, α4 to α3, and α2 to α0 based on the allocation destination information. As a result, other data α transmitted by the transmitting side ECU 3 can be restored.

Further, the management table 14 is shared between the ECU 3 and the ECU 4, and the used bits of the frames 101 to 103, the information of the empty bits, and the allocation destination information of the other data α are in the management table 14. CANID, that is, it is predetermined for each identification number. Therefore, the microcomputer 10 of the ECU 4 on the receiving side can recognize that when the bit data (for example, α8 to α5) is stored in the empty bit, it is the divided data α8 to α5 obtained by dividing the other data α. The bit data stored in this empty bit can be restored as divided data α8 to α5 of other data α.

Further, as shown in the present embodiment, it is desirable to allocate the divided data α8 to α5, α4 to α3, and α2 to α0 to transmission frames 101 to 103 with one bit or more, and a plurality of transmission frames 101 to 103. It is desirable to allocate the divided data α8 to α5, α4 to α3, and α2 to α0 obtained by dividing the other data α into the empty bits of.

(Second Embodiment)
11 to 13 show additional explanatory views of the second embodiment. The second embodiment is characterized in that when a plurality of empty bits are separated from each other in one transmission frame, other data α is divided and allocated in one transmission frame.

FIG. 11 shows an example of other data α to be transmitted separately from the frames 201 and 202, and the other data α is prepared with, for example, 4 bits. In the present embodiment, using the prior art, an embodiment of a process in which the ECU 4 restores the 4-bit data α to be transmitted as the data frame 203 by the ECU 3 is shown.

FIG. 12 shows the contents of the management table 114 shared by the ECUs 3 and 4, and also shows an image of transmission / reception processing. As shown in FIG. 12, the management table 114 stores that bits α3 to α2 of the other data α are allocated to the upper two bits of the four bits of all free bits in one frame 201. Further, it is stored that bits α1 to α0 of other data α are allocated to a part of the three bits of all free bits in one frame 202. That is, a plurality of empty bits are spaced apart from each other in one frame 202, and bits α3 to α2 and α1 to α0 of other data α are spaced apart and allocated in this frame 202. In addition, "empty" shown in FIG. 12 indicates that even if other data α is inserted, it becomes an empty bit.

As shown in FIG. 12, the ECU 3 outputs the frames 201 to 202 as transmission frames to the network 2, and the ECU 4 receives all the frames 201 and 202 as reception frames.

The microcomputer 10 of the ECU 4 serving as a receiving node receives the used bits as data of each CANID, refers to the management table 114, and stores the middle 2 bits of the data field of the frame 201, that is, bits bits 3 to bit 2 as the restored data αZ storage area. Set to the upper 2 bits of. Then, the microcomputer 10 of the ECU 4 sets the middle 1 bit of the data field of the frame 202, that is, the bit bit 5 to the middle bit bit 1 of the storage area of the restored data αZ, and similarly, the lower 1 bit of the data field of the frame 202. That is, bit bit0 is set to the lower bit bit0 of the storage area of the restored data αZ. Then, as shown in FIG. 13, the microcomputer 10 of the ECU 4 can restore the other data α as the restored data αZ.

As shown in the present embodiment, when there are a plurality of consecutive free bits in one transmission frame 202, the other data α is divided and assigned as bit data α1 and α0 at intervals in the transmission frame 202. There is. Therefore, the amount of data transmitted / received as continuous bits can be reduced as compared with the above-described embodiment, and security can be enhanced as compared with the above-mentioned embodiment.

(Third Embodiment)
14 to 18 show additional explanatory views of the third embodiment. In the third embodiment, the allocating unit divides and allocates the second data to one transmission frame together with the serial number and the free bits specified for each serial number by dividing the second data, and the transmitting unit divides the second data into one transmission in which the serial number is changed. It is characterized by transmitting frames multiple times.

FIG. 14 shows an example of the management table 314. The management table 314 shows the internal bit information when the CANID is 301. As shown in FIG. 14, although the upper 4 bits of the frame 301 are defined as used bits, the lower 2 bits bits 3 and bit 2 are allocated as the serial number setting area. Further, the lower 2 bits bit1 and bit0 are defined as areas for allocating other bits β according to the serial number. For example, when the serial numbers are "0" and "0", it indicates that the lower 2 bits bit1 and bit0 are assigned to the upper 2 bits β2 and β1 of the other bits β. For example, when the serial numbers are "0" and "1", it indicates that an empty bit and a lower 1 bit β0 of another bit β are assigned to the lower 2 bits bit1 and bit0. The management table 314 in which such information is stored is shared among the ECUs 3 to 5.

FIG. 15 shows an example of other data β. The other data β is prepared, for example, with a 3-bit amount of information. Hereinafter, using the prior art, a mode of processing in which the ECU 3 sets another 3-bit data β to be transmitted as the data frame 302 as an empty bit of the frame 301 and the ECU 4 restores the other data α will be shown. ..

FIG. 16 shows the transmission process of the ECU 3 on the transmitting side, and FIG. 17 shows the receiving process of the ECU 4 on the receiving side. As shown in FIG. 16, the microcomputer 10 of the ECU 3 creates a frame 301 at T31. Here, the microcomputer 10 of the ECU 3 refers to the management table 314, and creates the frame 301 by setting data in the bits 7 to bit 4 of the data field defined as “used” in the management table 314.

After that, the microcomputer 10 of the ECU 3 sets Nos. "0" and "0" indicating the serial numbers in the serial number setting bits 3 and 2 of the frame 301 in T32, respectively, and sets the empty bits bit1 and bit0 of the frame 301 in T33. Set bits bit2 and bit1 of the data β of. Then, the ECU 3 transmits the frame 301 at the T34.

After that, the microcomputer 10 of the ECU 3 sets Nos. "0" and "1" indicating the serial numbers in the serial number setting bits 3 and 2 of the frame 301 in T35, respectively, and sets the empty bits bit0 of the frame 301 in T36. Set the low-order bit bit0 of the data β of. Then, the ECU 3 transmits the frame 301 at T37. That is, the ECU 3 changes the serial number and transmits the frame 301 twice.

On the other hand, as shown in FIG. 17, when the microcomputer 10 of the ECU 4 receives the frame 301 in R31, the microcomputer 10 confirms the serial number of the frame 301 in R32 and R33, and the serial number is "0" "0" or "0". It is determined whether or not it is "0" or "1". When the microcomputer 10 of the ECU 4 receives a serial number other than this, the microcomputer 10 discards the frame 301.

Then, for example, when the serial number of the frame 301 is "0" or "0", it is determined as YES in R32, the used bit in the frame 301 is accepted as the data of the CANID 301 in the R34a, and the bits bit1 and bit0 of the frame 301 in the R34b. Is set in the upper 2 bits bit2 and bit1 of the restored data βZ, respectively. Further, a flag is set to set the serial numbers "0" and "0" to have been received, that is, to set the frame 301 corresponding to the serial numbers "0" and "0" to have been received.

Further, for example, when the serial number of the frame 301 is "0" or "1", it is determined as YES in R33, the bit used in the frame 301 is accepted as the data of the CANID 301 in the R36a, and the bit bit0 of the frame 301 in the R36b. Is set to the lower 1 bit bit0 of the restored data βZ. Here, the microcomputer 10 of the ECU 4 determines whether or not the serial numbers "0" and "0" have been received. The microcomputer 10 of the ECU 4 determines whether or not it has been received by determining whether or not the flag is set, and if it has not been received, determines NO in R37, exits this process, and sets the frame 301. The process is repeated from R31 until the serial numbers "0" and "0" are received.

On the contrary, in R37, the microcomputer 10 of the ECU 4 has received the serial numbers “0” and “0” in the R38 only when the serial numbers “0” and “0” have been received. The lower 1 bit received with the serial numbers No. "0" and "1" is combined to create a 3-bit restored data βZ. Then, the microcomputer 10 of the ECU 4 clears the flag that the serial numbers No. "0" and "0" are not received in R39, that is, the frame 301 is received corresponding to the serial numbers "0" and "0".

FIG. 18 shows an image of transmission / reception processing. As shown in FIG. 18, the ECU 3 sequentially outputs and transmits frames 301 having different serial numbers as transmission frames to the network 2, and the ECU 4 receives all of these frames 301 as reception frames. The middle 2 bits bit3 and bit2 of the frame 301 indicate the serial number, and the lower 2 bits bit1 and bit0 are predetermined in the management table 314 as data corresponding to the serial number.

Therefore, the transmitting side ECU 3 can grasp which free bit the other data β should be inserted by referring to the management table 314, and the receiving side ECU 4 microcomputer 10 refers to the management table 314. By doing so, it can be determined which free bit the other data β is inserted into. By referring to the management table 314, the ECU 4 on the receiving side can restore the bit bit1 of the serial numbers "0" and "0" of the frame 301 as the most significant bit bit2, and the serial numbers "0" and "0" of the frame 301 can be restored. Bit bit0 can be restored as middle bit bit1. Further, the bit bit0 of the serial numbers "0" and "1" of the frame 301 can be restored as the least significant bit bit0.

As a result, as shown in FIG. 19, the restored data βZ can be generated from the other data β, and it is not necessary to transmit the other data β as another frame 302 to the network 2, so that the bus load can be reduced. The ECU 3 may alternately transmit the n (however, n ≧ 1) th transmission data and the n + 1th transmission data, whereby the ECU 4 can alternately receive these data.

According to the present embodiment, a serial number is assigned to one transmission frame 301, another data β is divided and assigned to free bits specified for each serial number, and one transmission frame 301 whose serial number is changed is assigned. I try to send it multiple times. Therefore, one transmission frame 301 can be used to divide the other data β and transmit it in a plurality of times. Moreover, when the ECU 4 on the receiving side receives the plurality of transmission frames 301, the restored data βZ can be restored by referring to the allocation destination information in the management table 314 from these divided data.
Although the form in which the frame 301 is transmitted in two times is shown, the frame 301 may be transmitted in three or more times.

(Fourth Embodiment)
20 to 25 show additional explanatory views of the fourth embodiment. The first to third embodiments show a mode in which one other data α or β is divided and set as an empty bit in a data field of a frame, but in the fourth embodiment, a plurality of other data α and β are shown. A mode is shown in which β is divided and set as an empty bit in the data field of the transmission frames 401 to 404. In particular, the microcomputer 10 of the ECU 3 on the transmitting side is characterized in that the divided data of the plurality of other data α and β are separately allocated to the free bits of the plurality of transmission frames 401 to 404.

FIG. 20 shows an example of other data α and β. The other data α and β are prepared, for example, 3 bits and 7 bits, respectively. In the following, using the prior art, the ECU 3 on the transmitting side sets the 3-bit data α and the 7-bit data β to be transmitted as the data frames 405 and 406, respectively, as the empty bits of the frames 401 to 404. The mode in which the ECU 4 on the receiving side restores these data α and β is shown.

FIG. 21 shows an example of the management table 414. The management table 414 stores the internal bit information when the CANID is 401 to 404. As shown in FIG. 21, the upper 4 bits bit7 to bit4 of the frame 401 are defined as the bits to be used, but the lower middle 2 bits bit3 and bit2 are the upper 2 bits α2 of the other data α. It is assigned as α1. The least significant bit bit0 is assigned as the least significant bit β0 of the other data β.

Further, although the upper 6 bits bits 7 to 2 of the frame 402 are defined as the bits used, the lower middle 1 bit bit1 is assigned as the least significant bit α0 of the other data α. The least significant bit bit0 is assigned as the middle bit β1 of the other data β.

Further, although the upper 2 bits bits 7 to 6 and the lower 3 bits bits 2 to bit0 of the frame 403 are specified by the bits used, the intermediate intermediate bits bits 4 and 3 are the intermediate bits of other data β. It is assigned as bits β3 and β2. The middle bit bit5 of the frame 403 is defined as an empty bit. Further, although the upper 1 bit bit7 and the lower 4 bits bit3 to bit0 of the frame 404 are defined as the bits to be used, the intermediate intermediate bits bits 6 to bit4 are the intermediate bits β4 of other data β. It is assigned as β5 and β6. A management table 414 that stores such information is shared among the ECUs 3 to 5.

FIG. 22 shows the transmission process of the ECU 3 on the transmitting side, and FIG. 23 shows the receiving process of the ECU 4 on the receiving side. As shown in FIG. 22, the microcomputer 10 of the ECU 3 creates frames 401 to 404 in T41. Here, the microcomputer 10 of the ECU 3 refers to the management table 414, and creates frames 401 to 404 by setting data in the bits of the data field defined as "used" in the management table 414.

After that, the microcomputer 10 of the ECU 3 sets the empty bits bit3 and bit2 of the frame 401 to the bits 2 and bit1 of the other data α, respectively, and sets the empty bit bit0 of the frame 401 to the bit bit0 of the other data β. .. Then, the microcomputer 10 of the ECU 3 outputs the frame 401 to the network 2 at T43 and transmits the frame 401.

Further, the microcomputer 10 of the ECU 3 sets the bit bit0 of the other data α in the free bit bit1 of the frame 402 in T44, and sets the bit bit1 of the other data β in the free bit bit0 of the frame 402. Then, the microcomputer 10 of the ECU 3 outputs the frame 402 to the network 2 at T45 and transmits the frame 402. Further, the microcomputer 10 of the ECU 3 sets the empty bits bit4 and bit3 of the frame 403 in the T46 to set the bits 2 and bit1 of the other data β, and outputs and transmits the frame 403 to the network 2 in the T47.

Further, the microcomputer 10 of the ECU 3 sets the empty bit bit 6 of the frame 404 to the bit bit 4 of the other data β in T48, sets the empty bit bit 5 of the frame 404 to the bit bit 5 of the other data β, and sets the empty bit of the frame 404 to the empty bit bit. Set bit 6 of other data β to bit 4. Then, the microcomputer 10 of the ECU 3 outputs the frame 404 to the network 2 at T49 and transmits the frame 404.

On the other hand, as shown in FIG. 23, the microcomputer 10 of the ECU 4 waits for reception of frames 401 to 404 in R41 to R44. At this time, when the microcomputer 10. Bit2 is set to the upper two bits of the storage area of the restored data αZ, that is, bits bit2 and bit1. Thereby, the original data of the CANID 401 and the divided data α2 to α1 and β0 of the other data α and β can be distinguished from the received frame 401. Then, a flag is set in R46 to mark that the frame 401 has been received.

Further, when the microcomputer 10 of the ECU 4 receives the frame 402, it refers to the management table 414 and accepts the used bit in the frame 402 as the data of the CANID 402 in the R47a, and restores the middle bit bit1 of the data field of the frame 402 in the R47b. The lowest bit bit0 of the data αZ is set, and the lowest bit bit0 of the data field of the frame 402 is set to the middle bit bit1 of the restored data βZ. Thereby, the original data of CANID 402 and the divided data α0 and β0 of other data α and β can be distinguished from the received frame 402. Then, the microcomputer 10 of the ECU 4 sets a flag in R48 that the frame 402 has been received.

Further, when the microcomputer 10 of the ECU 4 receives the frame 403, the management table 414 is referred to, and the bits used in the frame 403 are accepted as the data of the CANID 403 in the R49a, and the middle bits bit4, bit3 of the data field of the frame 403 in the R49b. Is set to the middle bits bit2 and bit1 of the restored data βZ. Thereby, the original data of CANID 403 and the divided data β3 and β2 of other data β can be distinguished from the received frame 403. Then, the microcomputer 10 of the ECU 4 sets a flag that the frame 403 has been received in the R50.

Further, when the microcomputer 10 of the ECU 4 receives the frame 404, it refers to the management table 414 and accepts the used bit in the frame 404 as the data of the CANID 404 in the R51a, and receives the middle bit bit 6 of the data field of the frame 404 in the R51b. Set the middle bit bit4 of the restored data βZ to the middle bit bit4 of the data field of the frame 404, set the middle bit bit5 of the data field of the restored data βZ to the middle bit bit5 of the restored data βZ, and set the middle bit bit4 of the data field of the frame 404 to the restored data βZ. Set to medium bit bit6. Thereby, the original CANID 404 data and the divided data β6 to β4 of the other data β can be distinguished from the received frame 404.

After processing R51, the microcomputer 10 of the ECU 4 determines whether or not all the other frames 401 to 403 have been received in R52, and only when all the frames 401 to 404 have been received. , R53 restores the data α and β based on each received frame data. That is, all the data are combined to create restored data αZ and βZ, respectively. Then, the microcomputer 10 of the ECU 4 eliminates the received data in the frames 401 to 403 in R54, that is, clears the flag set as received in R46, R48, and R50. As a result, restored data αZ and βZ can be generated.

FIG. 24 shows an image of transmission / reception processing. As shown in FIG. 24, the ECU 3 outputs frames 401 to 404 as transmission frames to the network 2, and the ECU 4 receives all frames 401 to 404 as reception frames. Each free bit of frames 401 to 404 is predetermined in the management table 414 so as to correspond to each bit of data α and β. Therefore, the microcomputer 10 of the ECU 3 on the transmitting side can grasp which free bit each bit of the other data α and β should be inserted by referring to the management table 414, and the microcomputer 10 of the ECU 4 on the receiving side Can determine which free bit the other data α, β is inserted into by referring to the management table 414, whereby the restored data αZ, βZ can be generated as shown in FIG. 25. This eliminates the need to transmit the data α and β to the network 2 as separate frames 405 and 406, so that the bus load can be reduced.

(Other embodiments)
The present invention is not limited to the above-described embodiment, but can be variously modified and implemented, and can be applied to various embodiments without departing from the gist thereof. For example, the following modifications or extensions are possible.

For example, in the first embodiment, the receiving ECU 4 confirms the frames 101 to 103 output to the network 2 in the ascending order of the frames 101, 102, 103, but the order may be descending. , And may be replaced in any other order. This is the same in each of the second and subsequent embodiments, and the order of frame confirmation may be changed. Further, in the above-described embodiment, the description has been given with reference to the flowcharts, but the order of the processes shown in these flowcharts is only an example, and the processes may not be executed in the order shown in these flowcharts. .. That is, if the same or similar purpose as the above-described embodiment can be achieved, the processing order may be changed, the processing may be changed as necessary, or a part may be omitted as necessary. ..

In the above-described embodiment, the empty area is considered in bit units, and continuous free bits are described as "empty areas". However, it is not necessary to consider in bit units, and byte units may be used.
The communication controller 11 may be incorporated in the microcomputer 10. It is not limited to CAN, and can be applied to any communication system using a protocol having a format including an empty area.

Although each of the ECUs 3 to 5 is provided with and shared with the management tables 14, 114, 314 and 414, the management tables 14, 114, 314 and 414 are stored in another ECU or the like connected to the network 2. In addition, each ECU 3 to 5 may refer to the management tables 14, 114, 314, 414 through the network 2.

A part or all of the functions executed by the microcomputers 10 of the ECUs 3 to 5 may be configured in hardware by one or a plurality of ICs. It may be configured by combining a plurality of the above-mentioned embodiments. The reference numerals in parentheses described in the claims indicate an example of the correspondence with the specific means described in the above-described embodiment as one aspect of the present invention, and are technically of the present invention. It does not limit the range. An embodiment in which a part of the above-described embodiment is omitted as long as the problem can be solved can also be regarded as an embodiment. In addition, any conceivable embodiment can be regarded as an embodiment as long as it does not deviate from the essence of the invention specified by the wording described in the claims.

Although the present disclosure has been described in accordance with the embodiments described above, it is understood that the present disclosure is not limited to such embodiments or structures. The present disclosure also includes various variations and variations within a uniform range. In addition, various combinations and forms, as well as other combinations and forms, including one element, more, or less, are within the scope and ideology of the present disclosure.

In the drawing, 1 is a communication system, 2 is an in-vehicle network (network), 3 to 5 are ECUs (electronic control device: 3 is a transmission node, 4 is a reception node), 6 is an unauthorized device, and 10 is a microcomputer (10 of ECU 3 is). The allocation unit and the transmission unit: 10 of the ECU 4 is an identification unit and a restoration unit), 12 is a transmission unit, 13 is an allocation unit, and 14,114,314,414 are management tables.

Claims (8)

Communication in which the transmitting node (3) stores the first data in a transmission frame having a predetermined format and transmits the first data to the network (2), and the receiving node (4) receives the first data as a receiving frame through the network. The system (1) and the electronic control device (3) constituting the transmission node.
An allocation unit (13) that divides and allocates other second data to an empty area excluding the area to which the first data is allocated to the transmission frame, and
A transmission unit (12) for transmitting the divided data and the first data allocated by the allocation unit as a transmission frame is provided .
The first data is data sent and received for each identification number, and is
The empty area of the transmission frame and the allocation destination of the divided data are predetermined for each identification number.
The information of the empty area in the transmission frame and the allocation destination information of the divided data of the first data and the second data are stored in the management table (14,114,314,414) between the transmission node and the reception node. Electronic control device (3) shared by. Communication in which the transmitting node (3) stores the first data in a transmission frame having a predetermined format and transmits the first data to the network (2), and the receiving node (4) receives the first data as a receiving frame through the network. The system (1) and the electronic control device (4) constituting the receiving node.
The allocation unit (13) in which the transmission node divides and allocates the other second data to the empty area excluding the area in which the first data is allocated to the transmission frame, the divided data allocated by the allocation unit, and the first. When the transmission unit (12) for transmitting data as a transmission frame is provided.
An identification unit (19) that discriminates between the first data and the divided data of the second data from the received frames,
A restoration unit (20) that generates restoration data (αZ, βZ) based on the allocation destination information from the divided data is provided .
The first data is data sent and received for each identification number, and is
The empty area of the transmission frame and the allocation destination of the divided data are predetermined for each identification number.
The information of the empty area in the transmission frame and the allocation destination information of the divided data of the first data and the second data are stored in the management table (14,114,314,414) between the transmission node and the reception node. Electronic control device (4) shared by. Communication in which the transmitting node (3) stores the first data in a transmission frame having a predetermined format and transmits the first data to the network (2), and the receiving node (4) receives the first data as a receiving frame through the network. The system (1) and the electronic control device (3) constituting the transmission node.
An allocation unit (13) that divides and allocates other second data to an empty area excluding the area to which the first data is allocated to the transmission frame, and
A transmission unit (12) for transmitting the divided data and the first data allocated by the allocation unit as a transmission frame is provided .
The allocation unit divides and allocates the second data to the one transmission frame together with the serial number in the empty area specified for each serial number.
The transmission unit is an electronic control device (3) that transmits the one transmission frame having a changed serial number a plurality of times. Communication in which the transmitting node (3) stores the first data in a transmission frame having a predetermined format and transmits the first data to the network (2), and the receiving node (4) receives the first data as a receiving frame through the network. The system (1) and the electronic control device (4) constituting the receiving node.
The allocation unit (13) in which the transmission node divides and allocates the other second data to the empty area excluding the area in which the first data is allocated to the transmission frame, the divided data allocated by the allocation unit, and the first. When the transmission unit (12) for transmitting data as a transmission frame is provided.
An identification unit (19) that discriminates between the first data and the divided data of the second data from the received frames,
A restoration unit (20) that generates restoration data (αZ, βZ) based on the allocation destination information from the divided data is provided .
The allocation unit divides and allocates the second data to the one transmission frame together with the serial number in the empty area specified for each serial number.
The transmission unit is an electronic control device (4) that transmits the one transmission frame having a changed serial number a plurality of times. In the electronic control device (3, 4) according to any one of claims 1 to 4.
The second data is composed of a plurality of bits.
The allocation unit is an electronic control device that allocates the divided data to an empty area of the transmission frame in a state where the divided data is 1 bit or more. In the electronic control device (3, 4) according to any one of claims 1 to 4.
The allocation unit is an electronic control device that allocates the second data separately in the one transmission frame when a plurality of empty regions are separated from each other in the one transmission frame. In the electronic control device (3, 4) according to any one of claims 1 to 4.
The plurality of transmission frames are provided, and each of the plurality of transmission frames has an empty area.
The allocation unit is an electronic control device that divides and allocates one second data to an empty area of the plurality of transmission frames. In the electronic control device (3, 4) according to any one of claims 1 to 4.
There are a plurality of second data to be divided,
When the transmission unit transmits a plurality of second data using a plurality of transmission frames,
The allocation unit is an electronic control device that allocates the divided data of the plurality of second data to the empty areas of the plurality of transmission frames.

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