JPH11284643A - Bus interface device for transmission and bus interface device for reception - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the capacity of a generated message storage means or received message storage means by improving a time delay up to the transmission or processing of the latest message. SOLUTION: A bus interface device 20A for transmission is equipped with a message generating means 201 which generates a message to be sent to a bus; a generated message storage means 205 which further stores a message having the same message identifier if the message is not stored when the message generated by the message generating means is stored and overwrites the message to a message having the same message identifier when the message having the same message identifier is stored; a transmission message selecting means 203 which selects a message to be sent to the bus out of messages stored in the generated message storage means; and a message transmitting means 204 which sends the selected message to the bus according to the communication protocol of the bus system.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used for transmitting a message including a message identifier for identifying a type of a message to a bus in a bus system in which each device connected to the bus transmits and receives the message. A bus interface device (hereinafter, referred to as a “transmission bus interface device”) and a bus interface device (hereinafter, referred to as a “bus interface device”) used to receive a message from a bus.
This is referred to as a “receiving bus interface device”. ). For example, as a communication protocol of a bus system, CAN (Controller Area Network) is used.
rk) A transmission bus interface device and a reception bus interface device in a vehicle control bus system using a communication protocol (automatic driving system, engine control system, anti-lock brake system, constant speed traveling system, automatic transmission system, etc.). Things.

[0002]

2. Description of the Related Art A conventional bus system will be described with reference to the drawings. FIG. 13 shows a configuration diagram of a general bus system. In the figure, 10 is a bus, 20 is a conventional transmission bus interface device connected to the bus 10, and 30 is a reception bus interface device. For example, in a bus system used for vehicle control, the transmission bus interface device 20 has an automatic driving control device 40, the reception bus interface device 30 has a brake device 50,
The throttle device 60 and the like are connected.

FIG. 14 shows, for example, Japanese Patent Application Laid-Open No. 4-32690.
FIG. 1 is a configuration diagram of a conventional transmission bus interface device disclosed in Japanese Patent Publication No. In the figure, 10, 20, 4
0 is the same as that in FIG. 201-
Reference numeral 204 denotes a unit that constitutes the conventional transmission bus interface device 20. 201 is a message generating means for generating a message to be transmitted to the bus 10, 202 is a generated message storing means for temporarily storing the message generated by the message generating means 201, and 203 is a message stored in the generated message storing means 202 Of which
Transmission message selection means 204 for selecting a message to be transmitted to the bus 10, and transmission message selection means 20
This is a message transmitting means for transmitting the message selected in 3 to the bus 10 according to the communication protocol of the bus system.

Hereinafter, the operation of the conventional transmission bus interface device 20 will be described. Here, an example of a vehicle control bus system using a CAN communication protocol as a communication protocol of the bus system will be described. In addition,
Regarding the CAN communication protocol, the draft CAN standard IS
O / DIS 11898 or ISO standard 11519 (VA
N and CAN low-speed serial data communication).

FIG. 15 shows an operation flow of the message generation means 201 and the generated message storage means 202, and FIG. 16 shows an operation flow of the transmission message selection means 203 and the message transmission means 204.

First, the message generating means 201 and the generated message storing means 202 will be described. The message generating means 201 and the generated message storing means 202 transmit the message shown in FIG.
Perform the operation of For example, when instructing the brake pressure from the automatic driving control device 40 to the brake device 50 in FIG.
Generates a message to be transmitted to the bus 10 (STEP 10). Here, for example, a message as shown in FIG. 17 is generated. The message in FIG. 17 includes a message identifier indicating the purpose of controlling the brake pressure, a message identifier indicating the priority of the message, and numerical data indicating the brake command pressure. In this case, the message identifier is 10 and the brake command pressure is 1000.

When the automatic operation control device 40 shown in FIG. 13 issues a throttle opening instruction to the throttle device 60, a message having a message identifier different from that shown in FIG. 17 is generated as shown in FIG. .

Next, the generated message is stored in the generated message storage means 202 (STE).
P20). This generated message storage means 202
As shown in FIG. 9, the message generated by the message generating means 201 is additionally stored regardless of the message identifier and the data content.

Next, the operation of the transmission message selection means 203 and the message transmission means 204 will be described. Transmission message selection means 203 and message transmission means 204
When the power supply of the transmission bus interface device 20 is turned on, the operation of FIG. 16 is repeatedly executed. First, the message transmitting means 204 determines whether a message can be transmitted to the bus 10 (STEP 30). Here, C
In accordance with the AN communication protocol, it is determined whether or not the bus 10 is in an idle state. If the idle state is detected, it is determined that a message can be transmitted to the bus 10.

Next, when the message transmission means 204 determines that the message can be transmitted to the bus 10, the transmission message selection means 203
2 to check whether a message is stored (ST
EP40). If it is stored, the transmission message selection means 203 selects a message to be transmitted to the bus 10 (STEP 50). This transmission message selection means 2
03 is a FIFO (FiFi) for selecting a message stored in the generated message storage unit 202 for the longest time.
A message to be transmitted is selected using an rst In First Out method. Next, the message transmission means 204 transmits the message selected by the transmission message selection means 203 to the bus 1 in accordance with the CAN communication protocol.
After transmitting to “0” (STEP 60), the process returns to STEP 30. Note that the transmitted message is deleted from the generated message storage unit 202.

When a plurality of messages having different message identifiers are stored in the generated message storage means 202, the transmission message selection means 203 compares the message identifiers and determines the message having the smallest message identifier, that is, the message having the lowest priority. Higher messages may be selected first. Here, the smaller the message identifier, the higher the priority.

Here, the message generating means 20
1 shows an example in which a message to be transmitted to the bus 10 is generated, but a means for inputting a message from outside is provided instead of the message generating means 201, and the message is generated by a processing device external to the transmission bus interface device 20. The received message may be input as a message to be transmitted to the bus 10.

Further, here, the message transmitting means 2
Although the example in which the transmission message selection means 203 operates after it has determined that the message transmission can be transmitted to the bus 10 has been described, the timing at which the transmission message selection means 203 operates varies, for example, every fixed time period, or It may be activated each time a new message is stored in the generated message storage unit 202. In such a case, when the message transmission unit 204 determines that the message can be transmitted to the bus 10, the message transmission unit 204 immediately transmits the message selected by the transmission message selection unit 203.

FIG. 20 shows, for example, Japanese Patent Application Laid-Open No. 4-32689.
FIG. 9 is a configuration diagram of a conventional reception bus interface device disclosed in Japanese Patent Application Laid-Open Publication No. 9-99. In the figure, 10, 30, 5
0 is the same as that in FIG. 301-
Reference numeral 304 denotes a unit that constitutes the conventional reception bus interface device 30. 301 is a message receiving means for receiving a message from the bus 10 in accordance with the communication protocol of the bus system, 302 is a received message storing means for temporarily storing the message received by the message receiving means 301, and 303 is a received message storing means 302 A processing message selection unit 304 for selecting a message to be processed among the messages being processed, and a message processing unit 304 for processing the message selected by the processing message selection unit 303.

Hereinafter, the operation of the conventional reception bus interface device 30 will be described. Here, an example of a vehicle control bus system using the CAN communication protocol as the communication protocol of the bus system will be described.

FIG. 21 shows an operation flow of the message receiving means 301 and the received message storage means 302, and FIG. 22 shows an operation flow of the processing message selecting means 303 and the message processing means 304.

First, the message receiving means 301 and the received message storage means 302 will be described. The message receiving means 301 and the received message storing means 302 receive the message shown in FIG.
1 is performed. For example, when the automatic driving control device 40 instructs the brake device 50 to apply the brake pressure in FIG. 13, the message receiving unit 301 in FIG. 20 receives a message from the bus 10 according to the CAN communication protocol (STEP 110).

Next, the received message is stored in the received message storage means 302 (STEP 120).
Here, the received message is stored, for example, in a format as shown in FIG. FIG. 17 includes a message identifier indicating the purpose of controlling the brake pressure, a message identifier indicating the priority of the message, and numerical data indicating the brake command pressure. In this case, the message identifier is 10,
The brake command pressure is 1000.

When the automatic driving control device 40 in FIG. 13 issues an instruction to switch the automatic driving mode to the brake device 50, as shown in FIG. 23, a message having a different message identifier from the message in FIG. Received and stored.

Here, the received message storage means 302
24, as shown in FIG. 24, is additionally stored regardless of the message identifier and the data content.

Next, the operation of the processing message selection means 303 and the message processing means 304 will be described. Processing message selection means 303 and message processing means 304
When the power of the receiving bus interface device 30 is turned on, the operation of FIG. 22 is repeatedly executed. First, the processing message selecting unit 303 sets the received message storing unit 3
02 to check whether a message is stored (S
If it is stored, the processing message selection means 303 selects a message to be processed (S130).
TEP140). This processing message selection means 303
Is a FIFO (Firsts) that selects a message stored in the received message storage unit 302 for the longest time.
The message to be processed is selected using the (tIn First Out) method.

Next, the message processing means 304 processes the message selected by the processing message selecting means 303 (STEP 150). The message processing here is, for example, if the message identifier of the processing message is a message for the purpose of controlling the brake pressure,
According to the numerical data of the message, the brake device 50
If the message identifier of the processing message is a message for instructing the automatic operation mode switching, the automatic operation mode of the brake device 50 is switched according to the numerical data of the message. That is. ST after processing the message
It returns to EP130. The processed message is deleted from the received message storage means 302.

When a plurality of messages having different message identifiers are stored in the received message storage means 302, the processing message selection means 303 compares the message identifiers and determines the message with the smallest message identifier, that is, the message with the lowest priority. Higher messages may be selected first. Here, the smaller the message identifier, the higher the priority.

Here, the message processing means 30
4 shows an example in which a message is processed, but a means for outputting a message to the outside is provided instead of the message processing means 304, and the message selected by the processing message selection means 303 is processed outside the reception bus interface device 30. The message may be output to a device, and the message may be processed by an external processing device.

[0025]

In the conventional transmission bus interface device as described above, an input or generated message is additionally stored in the generated message storage means 202 regardless of the message identifier. 25, when a situation occurs in which the processing for transmitting the message is slower than the processing for inputting or generating the message, as shown in FIG. 204 sequentially selects messages using the FIFO method and transmits all messages stored in the generated message storage means 202 to the bus 10, so that a large time delay occurs until the latest message is transmitted.
As a result, there is a problem that it is difficult to realize a bus system that performs control in real time.

Further, in order to prevent a situation in which a generated message cannot be additionally stored due to a limited storage capacity of the generated message storage means 202 as shown in FIG. 26, it is necessary to provide a large-capacity generated message storage means 202. There was a problem that it was expensive.

Furthermore, the conventional receiving bus interface device has the same problem as the generated message storage means 202 in the received message storage means 302.

The present invention has been made to solve the above-mentioned problem, and can improve the time delay until the latest message is transmitted or processed, and the storage capacity of the generated message storage means or the received message storage means. It is an object of the present invention to obtain a transmission bus interface device and a reception bus interface device that can reduce the size of the transmission bus interface device.

[0029]

A transmission bus interface device according to the present invention is a bus system in which a plurality of devices connected to a bus transmit and receive a message including a message identifier for identifying a type of a message.
When a message to be transmitted to the bus is input from an external processing device or a message input / generation unit that generates the message by itself, and a message input or generated by the message input / generation unit is stored, a message having the same message identifier is stored. Message storage means for additionally storing if not stored, and overwriting and storing the message with the same message identifier when storing the message with the same message identifier; A transmission message selection unit for selecting a message to be transmitted, and a message transmission unit for transmitting the message selected by the transmission message selection unit to the bus according to a communication protocol of the bus system.

Further, the transmission bus interface device according to the present invention further comprises a message identifier database referred to when the message storage means stores a message, wherein the message storage means is provided by the message input / generation means. When storing the input or generated message, it is the message of the message identifier registered in the message identifier database, and, if the message of the same message identifier is stored, overwrite and store the message of the same message identifier, A message with a message identifier registered in the message identifier database and not storing a message with the same message identifier, and a message with a message identifier not registered in the message identifier database. In the case of over-di it is to add memory.

Further, the transmission bus interface device according to the present invention further comprises a message identifier database referred to when the message storage means stores a message, wherein the message storage means is provided by the message input / generation means. When storing the input or generated message is a message of the message identifier not registered in the message identifier database, and, if the message of the same message identifier is stored, overwrite and store the message of the same message identifier, If the message has a message identifier not registered in the message identifier database and the message having the same message identifier is not stored, and if the message identifier is not registered in the message identifier database. If the message is to add memory.

A receiving bus interface device according to the present invention provides a bus system in which a plurality of devices connected to a bus transmit and receive a message including a message identifier for identifying a type of a message, according to a communication protocol of the bus system. Message receiving means for receiving a message from the bus, and storing the message received by the message receiving means, if the message with the same message identifier is not stored, additionally storing the message with the same message identifier; Message storage means for overwriting and storing a message having the same message identifier when there is a message, processing / output message selecting means for selecting a message to be processed or output to an external processing device among the messages stored in the message storage means, Said Physical / output message itself a message selected by the selection means treatment or, in which a message processing / output means for outputting to said external processing device.

Further, the receiving bus interface device according to the present invention further comprises a message identifier database referred to when the message storage means stores a message, and the message storage means receives the message by the message reception means. When memorizing a message,
If the message is a message with the message identifier registered in the message identifier database, and the message with the same message identifier is stored, the message is overwritten and stored in the message with the same message identifier, and the message is registered in the message identifier database. If the message is an identifier and the message with the same message identifier is not stored, or if the message has a message identifier not registered in the message identifier database, the message is additionally stored.

Further, the receiving bus interface device according to the present invention further comprises a message identifier database referred to when the message storage means stores a message, and the message storage means receives the message by the message reception means. When memorizing a message,
If the message is a message with a message identifier not registered in the message identifier database, and a message with the same message identifier is stored, the message is overwritten and stored in the message with the same message identifier, and the message is not registered in the message identifier database. If the message is an identifier message and the message with the same message identifier is not stored, or if the message has a message identifier registered in the message identifier database, it is additionally stored.

[0035]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 A transmission bus interface device according to Embodiment 1 of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a configuration of a transmission bus interface device according to Embodiment 1 of the present invention. In the drawings, the same reference numerals indicate the same or corresponding parts.

The transmission bus interface device 20A of the first embodiment is a vehicle control bus system using a CAN communication protocol as the communication protocol of the bus system, as in the conventional example. In FIG.
Reference numerals 1, 203, and 204 are the same as those in the conventional example, and a description thereof will be omitted. Reference numeral 205 denotes a generated message storage unit that temporarily stores the message generated by the message generation unit 201.

Next, the operation of the transmission bus interface device according to the first embodiment will be described. Message generation means 2
FIG. 2 shows an operation flow of the generated message storage unit 205. The message generating means 201 and the generated message storing means 205 execute the operation of FIG. 2 each time a message needs to be transmitted to the bus, as in the conventional example.
The operations of the transmission message selection means 203 and the transmission message transmission means 204 are the same as those in the conventional example, and the description is omitted.

The message generating means 201 and the generated message storing means 205 will be described with reference to the operation flow of FIG. In FIG. 2, the operation of generating a message by the message generating means 201 (STEP 10) is the same as that of the conventional example, and a description thereof will be omitted.

Next, the generated message storage means 205
The message generated by the message generating means 201 is stored (STEP 22). This generated message storage means 2
When storing the generated message, as shown in FIG. 3, if the message having the same message identifier is not stored as shown in FIG.

On the other hand, as shown in FIG. 4, if the generated message storage means 205 stores a message with the same message identifier, the generated message storage means 205 overwrites a transmission message with the same message identifier.

In the first embodiment, only the newest message having the same message identifier is stored in the generated message storage means 205 in this manner. Even when a situation that is slower than the generation processing occurs, the time delay until the latest message is transmitted is smaller than before. In addition, the bus usage rate becomes smaller than before. Further, when the number of types of message identifiers of the message to be generated is known, it is sufficient to provide the generated message storage unit 205 by the capacity of the number of types at the maximum.
The storage capacity of the generated message storage unit 205 can be smaller than before.

Embodiment 2 A transmission bus interface device according to a second embodiment of the present invention will be described with reference to the drawings. FIG. 5 is a block diagram showing a configuration of a transmission bus interface device according to Embodiment 2 of the present invention.

The transmission bus interface device 20B according to the second embodiment is, like the first embodiment, a vehicle control bus system using a CAN communication protocol as a communication protocol of the bus system. In FIG. 5, reference numerals 201, 203, and 204 are the same as those in the conventional example, and thus description thereof is omitted. Reference numeral 206 denotes a generated message storage unit that temporarily stores the message generated by the message generation unit 201, and 207 denotes a generated message storage unit 206.
Is a message identifier database referred to when storing the message generated by the message generating means 201.

Next, the operation of the transmission bus interface device according to the second embodiment will be described. Message generation means 2
FIG. 6 shows the operation flow of 01 and the generated message storage means 206. The message generating means 201 and the generated message storing means 206 execute the operation of FIG. 6 every time a message needs to be transmitted to the bus, as in the conventional example.
The operations of the transmission message selection means 203 and the transmission message transmission means 204 are the same as those in the conventional example, and the description is omitted.

The message generating means 201 and the generated message storing means 206 will be described with reference to the operation flow of FIG. In FIG. 6, the operation (STEP 10) until the message generation means 201 generates a transmission message is as follows.
The description is omitted because it is the same as the conventional example.

Next, the generated message storage means 206
It is determined whether the message identifier of the message generated by the message generating means 201 is registered in the message identifier database 207 (STEP 24).

When the message identifier of the message generated by the message generating means 201 is registered in the message identifier database 207, the generated message storing means 206 stores the message in the same manner as in the first embodiment (STEP 26). . That is, as shown in FIG. 3, if the message with the same message identifier is not stored in the generated message storage means 206, it is additionally stored in the generated message storage means 206, and as shown in FIG.
If you remember the message with the same message identifier,
Overwrite and store the message with the same message identifier.

When the message identifier of the message generated by the message generating means 201 is not registered in the message identifier database 207, the generated message storage means 206 stores the generated message in the same manner as in the conventional example (STEP 28). That is, as shown in FIG. 19, the message generated by the message generation unit 201 is additionally stored in the generated message storage unit 206 regardless of the message identifier.

In the second embodiment, only the message with the message identifier registered in the message identifier database 207 and only the latest message with the same message identifier are stored in the message identifier database 207 in this manner. Since all the messages with the message identifiers which are not stored are additionally stored, it is possible to cope with both the message in which only the latest message is to be stored and the message in which all the messages are to be stored as required.

In the second embodiment, the message of the message identifier registered in the message identifier database 207 is stored in the same manner as in the first embodiment, and the message of the message identifier not registered in the message identifier database 207 is stored. The message is stored in the same manner as in the conventional example. Contrary to this example, a message having a message identifier not registered in the message identifier database 207 is stored in the same manner as in the first embodiment. The message of the message identifier registered in 207 may be stored in the same manner as in the conventional example.

Also, in the first and second embodiments, the example in which the message generating means 201 generates a message to be transmitted to the bus 10 has been described. And a means for inputting a message from the transmission bus interface device 20A, 20B. A message generated by a processing device outside the transmission bus interface device 20A, 20B may be input as a message to be transmitted to the bus 10.

Embodiment 3 FIG. A receiving bus interface device according to a third embodiment of the present invention will be described with reference to the drawings. FIG. 7 is a block diagram showing a configuration of a receiving bus interface device according to Embodiment 3 of the present invention.

The receiving bus interface device according to the third embodiment is a vehicle control bus system using the CAN communication protocol as the communication protocol of the bus system, as in the conventional example. In FIG. 1, 301, 3
03 and 304 are the same as those in the conventional example, and the description is omitted. Reference numeral 305 denotes a received message storage unit for temporarily storing the message received by the message receiving unit 301.

Next, the operation of the receiving bus interface device according to the third embodiment will be described. Message receiving means 3
FIG. 8 shows the operation flow of the received message storage unit 305 in the case of the first message. The message receiving means 301 and the received message storage means 305 execute the operation of FIG. 8 every time a message needs to be received from the bus, as in the conventional example. The operations of the processing message selection means 303 and the message processing means 304 are the same as those in the conventional example, and the description is omitted.

The message receiving means 301 and the received message storing means 305 will be described with reference to the operation flow of FIG. In FIG. 8, the operation of receiving a message by the message receiving means 301 (STEP 110) is the same as in the conventional example, and therefore will not be described.

Next, the received message storage means 305
The message received by the message receiving means 301 is stored (STEP 122). When storing the received message, as shown in FIG. 9, the received message storage means 305 additionally stores a message having the same message identifier as shown in FIG.

On the other hand, as shown in FIG. 10, if the received message storage means 305 stores a message with the same message identifier, it overwrites the received message with the same message identifier.

In the third embodiment, only the newest message having the same message identifier is stored in the received message storage means 305 in this manner, so that the operation for processing the message receives the message. Even when a situation slower than the operation occurs, the time delay until the latest message is processed is smaller than before. In addition, a message processing unit that operates at a lower speed than conventional messages can be used. Further, when the number of types of message identifiers of the received message is known, the received message storage means 305 may be provided with the maximum number of types of the message identifiers. Can be smaller.

Embodiment 4 FIG. Embodiment 4 A receiving bus interface device according to Embodiment 4 of the present invention will be described with reference to the drawings. FIG. 11 shows Embodiment 4 of the present invention.
1 is a block diagram showing a configuration of a receiving bus interface device according to the present invention.

The receiving bus interface device of the fourth embodiment is similar to that of the third embodiment in a vehicle control bus system using a CAN communication protocol as a communication protocol of the bus system. In FIG. 11, 3
01, 303, and 304 are the same as those in the conventional example, and the description is omitted. 306 is a received message storage means for temporarily storing the message received by the message receiving means 301, and 307 is a message identifier database which the received message storage means 306 refers to when storing the message received by the message receiving means 301. is there.

Next, the operation of the receiving bus interface device according to the fourth embodiment will be described. Message receiving means 3
FIG. 12 shows an operation flow of the received message storage means 306 in the step S01. The message receiving means 301 and the received message storing means 306 execute the operation shown in FIG. 12 every time a message needs to be received from the bus as in the conventional example. The operations of the processing message selection means 303 and the message processing means 304 are the same as those in the conventional example, and the description is omitted.

The message receiving means 301 and the received message storing means 306 will be described with reference to the operation flow of FIG. In FIG. 12, operation until message receiving means 301 receives a received message (STEP 11)
0) is the same as in the conventional example, and will not be described.

Next, the received message storage means 306
It is determined whether the message identifier of the message received by the message receiving means 301 is registered in the message identifier database 307 (STEP 124).

When the message identifier of the message received by message receiving means 301 is registered in message identifier database 307, received message storing means 306 stores the message in the same manner as in the third embodiment (STEP 126). . That is, as shown in FIG. 9, if a message with the same message identifier is not stored, additional storage is performed. As shown in FIG. 10, if a message with the same message identifier is stored, a received message with the same message identifier is stored. Overwrite and store.

When the message identifier of the message received by the message receiving means 301 is not registered in the message identifier database 307, the received message storage means 306 stores the received message in the same manner as in the conventional example (STEP 128). That is, as shown in FIG. 24, the message received by the message receiving unit 301 is additionally stored in the received message storage unit 306 regardless of the message identifier.

In the fourth embodiment, only the message with the message identifier registered in the message identifier database 307 and only the latest message with the same message identifier are stored in the message identifier database 307 in this manner. Since all the messages with the message identifiers which are not stored are additionally stored, it is possible to cope with both the message in which only the latest message is to be stored and the message in which all the messages are to be stored as required.

In the fourth embodiment, the message of the message identifier registered in the message identifier database 307 is stored in the same manner as in the third embodiment, and the message of the message identifier not registered in the message identifier database 307 is stored. Although the message is stored in the same manner as in the conventional example, the message of the message identifier not registered in the message identifier database 307 is stored in the same manner as in the third embodiment. The message of the message identifier registered in 307 may be stored in the same manner as in the conventional example.

In the third and fourth embodiments, the example in which the message processing means 304 processes a message has been described. However, as in the conventional example, a means for outputting a message to the outside instead of the message processing means 304. And the message selected by the processing message selecting means 303 may be output to a processing device outside the receiving bus interface devices 30A and 30B, and the message may be processed by the external processing device.

[0069]

As described above, the transmission bus interface device according to the present invention provides a bus system in which a plurality of devices connected to a bus transmit and receive a message including a message identifier for identifying a type of a message. When a message to be transmitted to the bus is input from an external processing device or a message input / generation unit that generates the message by itself, and a message input or generated by the message input / generation unit is stored, a message having the same message identifier is stored. If you have not memorized, additionally memorize,
Message storing means for overwriting and storing a message having the same message identifier when a message having the same message identifier is stored, and transmitting message selection for selecting a message to be transmitted to the bus among the messages stored in the message storing means Means for transmitting a message selected by the transmission message selecting means to the bus in accordance with the communication protocol of the bus system, so that the process of transmitting a message to the bus is more than the process of generating a message. Even when a late situation occurs, the time delay until the latest message is transmitted is smaller than before. In addition, the bus usage rate becomes smaller than before. As a result, it is possible to provide a transmission bus interface device capable of realizing a bus system that performs control in real time more easily than before. Furthermore, if the number of types of message identifiers of the message to be generated is known, it is sufficient to provide the message storage means at the maximum in the capacity of the number of types, and the storage capacity of the message storage means can be made smaller than before, This has the effect of providing a transmission bus interface device that is less expensive than in the past.

Further, as described above, the transmission bus interface device according to the present invention further comprises a message identifier database referred to when the message storage means stores a message, and the message storage means stores the message When storing a message input or generated by the input / generation means, if the message is a message with a message identifier registered in the message identifier database and a message with the same message identifier is stored, the message with the same message identifier is stored. Overwrites the message with the message identifier registered in the message identifier database, and stores the message with the same message identifier and the message not registered in the message identifier database. Since a message with a message identifier is additionally stored, a transmission bus interface device capable of responding to both a request to store only the latest message and a request to store all messages according to the request can be provided. To play.

Further, as described above, the transmission bus interface device according to the present invention further includes a message identifier database referred to when the message storage means stores a message, and wherein the message storage means stores the message. When storing a message input or generated by the input / generation means, if the message has a message identifier that is not registered in the message identifier database and a message having the same message identifier is stored, the message has the same message identifier. If the message is a message with a message identifier not registered in the message identifier database, and the message with the same message identifier is not stored, and is registered in the message identifier database. Since a message having a message identifier is additionally stored, a transmission bus interface device capable of responding to both a request to store only the latest message and a request to store all messages according to the request can be provided. To play.

As described above, the receiving bus interface device according to the present invention provides a bus system in which a plurality of devices connected to a bus transmit and receive a message including a message identifier for identifying a type of a message. Message receiving means for receiving a message from the bus according to the communication protocol of the system, and when storing the message received by the message receiving means, if the message with the same message identifier is not stored, the message is additionally stored, and Message storing means for overwriting and storing a message having the same message identifier when the message is stored;
Processing / output message selecting means for selecting a message to be processed or output to an external processing device from among the messages stored in the message storage means; and processing the message selected by the processing / output message selecting means by itself or Of messages output to the processing unit
Because of the provision of the output means, even when a situation where processing of a message is slower than receiving a message occurs, a time delay until processing of the latest message is smaller than before. As a result, it is possible to provide a receiving bus interface device capable of realizing a bus system that performs control in real time more easily than before. In addition, a message processing unit that operates at a lower speed than conventional messages can be used. Furthermore, when the number of types of message identifiers of the received message is known, it is sufficient to provide the message storage means only by the capacity of the maximum number of types, and the storage capacity of the message storage means can be made smaller than before, This has the effect of providing a receiving bus interface device that is less expensive than in the past.

As described above, the receiving bus interface device according to the present invention further includes a message identifier database referred to when the message storage means stores a message, and the message storage means stores the message When storing the message received by the receiving means, when storing the message with the message identifier registered in the message identifier database and storing the message with the same message identifier, the message is overwritten and stored in the message with the same message identifier. A message having a message identifier registered in the message identifier database and not storing a message having the same message identifier, and a message identifier not registered in the message identifier database Since in the case of the message is additionally stored exhibits requests and you want to store only the most recent message, both requests to be stored all messages, an effect of providing a receiving bus interface unit that can be used for on demand.

As described above, the receiving bus interface device according to the present invention further includes a message identifier database referred to when the message storage means stores a message, and the message storage means stores the message When storing the message received by the receiving means, if the message is a message with a message identifier not registered in the message identifier database and a message with the same message identifier is stored, the message is overwritten and stored in the message with the same message identifier. A message with a message identifier not registered in the message identifier database, and
If a message with the same message identifier is not stored and if the message has a message identifier registered in the message identifier database, additional storage is performed. Therefore, a request to store only the latest message and a request to store all messages are required. An advantage is provided in that a reception bus interface device that can respond to both requests can be provided.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a transmission bus interface device according to Embodiment 1 of the present invention.

FIG. 2 is a flowchart showing an operation of the transmission bus interface device according to the first embodiment of the present invention.

FIG. 3 is a diagram showing an operation of the transmission bus interface device according to the first embodiment of the present invention.

FIG. 4 is a diagram illustrating an operation of the transmission bus interface device according to the first embodiment of the present invention.

FIG. 5 is a block diagram showing a configuration of a transmission bus interface device according to Embodiment 2 of the present invention.

FIG. 6 is a flowchart showing an operation of the transmission bus interface device according to Embodiment 2 of the present invention.

FIG. 7 is a block diagram showing a configuration of a receiving bus interface device according to a third embodiment of the present invention.

FIG. 8 is a flowchart showing an operation of the receiving bus interface device according to Embodiment 3 of the present invention.

FIG. 9 is a diagram showing an operation of the receiving bus interface device according to Embodiment 3 of the present invention.

FIG. 10 is a diagram showing an operation of a receiving bus interface device according to a third embodiment of the present invention.

FIG. 11 is a block diagram showing a configuration of a receiving bus interface device according to Embodiment 4 of the present invention.

FIG. 12 is a flowchart showing an operation of the receiving bus interface device according to Embodiment 4 of the present invention.

FIG. 13 is a block diagram showing a configuration of a conventional bus system.

FIG. 14 is a block diagram showing a configuration of a conventional transmission bus interface device.

FIG. 15 is a flowchart showing the operation of a conventional transmission bus interface device.

FIG. 16 is a flowchart showing the operation of a conventional transmission bus interface device.

FIG. 17 is a diagram showing a configuration of a message in a conventional transmission bus interface device.

FIG. 18 is a diagram showing a configuration of a message of a conventional transmission bus interface device.

FIG. 19 is a diagram showing a message storage operation of a conventional transmission bus interface device.

FIG. 20 is a block diagram showing a configuration of a conventional reception bus interface device.

FIG. 21 is a flowchart showing the operation of a conventional reception bus interface device.

FIG. 22 is a flowchart showing the operation of a conventional reception bus interface device.

FIG. 23 is a diagram showing the structure of a message in a conventional receiving bus interface device.

FIG. 24 is a diagram showing a message storing operation of the conventional receiving bus interface device.

FIG. 25 is a diagram showing a problem of a conventional transmission bus interface device.

FIG. 26 is a diagram showing a problem of a conventional transmission bus interface device.

[Explanation of symbols]

20A, 20B Transmission bus interface device, 30
A, 30B receiving bus interface device, 201
Message generating means, 203 transmitting message selecting means, 204 message transmitting means, 205, 206 generated message storing means, 207 message identifier database, 301 message receiving means, 303 processing message selecting means, 304 message processing means, 3
05, 306 Received message storage means, 307 Message identifier database.

Claims (6)

[Claims] In a bus system in which a plurality of devices connected to a bus transmit and receive a message including a message identifier for identifying a type of a message, a message to be transmitted to the bus is input from an external processing device; Or a message input / generation unit that generates the message by itself, and when storing a message input or generated by the message input / generation unit, if a message with the same message identifier is not stored, the message is additionally stored, and a message with the same message identifier is stored. Message storing means for overwriting and storing a message having the same message identifier when stored; transmitting message selecting means for selecting a message to be transmitted to the bus among messages stored in the message storing means; The menu selected by the selection means Transmitting bus interface unit being characterized in that a message transmission means for transmitting a message to the bus in accordance with the communication protocol of the bus system. 2. The apparatus according to claim 1, further comprising a message identifier database referred to when the message storage means stores the message, wherein the message storage means stores the message input or generated by the message input / generation means. If the message is a message with a message identifier registered in the message identifier database, and the message with the same message identifier is stored, the message is overwritten and stored in the message with the same message identifier, and the message identifier registered in the message identifier database The message is additionally stored when the message does not store the message with the same message identifier and when the message has a message identifier not registered in the message identifier database. 2. The transmission bus interface device according to 1. 3. The apparatus according to claim 1, further comprising a message identifier database referred to when the message storage means stores the message, wherein the message storage means stores the message input or generated by the message input / generation means. If the message is a message with a message identifier not registered in the message identifier database, and stores a message with the same message identifier, the message is overwritten and stored in the message with the same message identifier, and the message identifier is not registered in the message identifier database. And if the message does not store the message with the same message identifier and if the message has a message identifier registered in the message identifier database, the message is additionally stored. Item 2. The transmission bus interface device according to Item 1. 4. A bus system in which a plurality of devices connected to a bus transmit and receive a message including a message identifier for identifying a type of a message, wherein a message is received from the bus according to a communication protocol of the bus system. Means for storing a message received by the message receiving means, when a message with the same message identifier is not stored, additionally storing the message, and when storing a message with the same message identifier, a message with the same message identifier Message storage means for overwriting and storing the message, processing / output message selection means for selecting a message to be processed or output to an external processing device among messages stored in the message storage means, and selection by the processing / output message selection means Done Themselves sage processing or receiving bus interface unit being characterized in that a message processing / output means for outputting to said external processing device. 5. The apparatus according to claim 1, further comprising a message identifier database referred to when the message storage means stores the message, wherein the message storage means stores the message received by the message reception means in the message identifier database. It is a message of the registered message identifier, and, when the message of the same message identifier is stored, overwrites and stores the message of the same message identifier, and is the message of the message identifier registered in the message identifier database. 5. The receiving device according to claim 4, wherein the message is additionally stored when a message with the same message identifier is not stored and when the message has a message identifier not registered in the message identifier database. Bus interface device. 6. The apparatus according to claim 1, further comprising a message identifier database referred to when the message storage means stores the message, wherein the message storage means stores the message received by the message reception means in the message identifier database. The message has a message identifier that has not been registered, and
If a message with the same message identifier is stored, the message with the same message identifier is overwritten and stored, and the message is a message with a message identifier not registered in the message identifier database, and the message with the same message identifier is not stored. 5. The receiving bus interface device according to claim 4, wherein a message is additionally stored in a case and a message with a message identifier registered in the message identifier database.