JP4488345B2 - In-vehicle electronic control unit communication device - Google Patents

Description

  The present invention relates to a communication device for an in-vehicle electronic control device that rewrites a control program stored in a plurality of electronic control units mounted on a vehicle and connected to each other via a communication line.

  2. Description of the Related Art Conventionally, a CAN communication system is known that performs data communication between a plurality of electronic control units (nodes) that are connected to each other via a communication line (CAN bus) and each have a control unit (CAN controller unit). CAN communication is a protocol for performing bidirectional serial communication via a differential serial bus (see, for example, Patent Document 1).

  In such a CAN communication system, each node sends out data with an identification ID code of its own node toward the CAN bus, and when the data is transmitted, the CAN bus is not dedicated to data by other nodes In this case, data sent from the node flows through the CAN bus and is received by another node. On the other hand, when the CAN bus is exclusively used for data by other nodes, the data to be sent from the node is in a standby state in the CAN controller unit. If the data of the node in the standby state is only one, the data of the node flows through the CAN bus when the CAN bus is free. On the other hand, when there are a plurality of standby node data, the node data having the highest priority based on the ID code flows through the CAN bus before the other standby data.

JP 2001-142996 A

  By the way, in order to improve production efficiency, the hardware specifications of multiple electronic control units installed in the vehicle are unified regardless of the vehicle type and destination, and a control program corresponding to the vehicle type and destination is provided on the production line. It has been studied to store in the memory of the electronic control unit. In addition, when a malfunction occurs in the performance of the produced vehicle, it may be necessary to change the control program of the mounted electronic control unit.

  In such a case, the control program of the electronic control unit can be rewritten using the CAN communication system, but many electronic control units (nodes) communicate using a common communication line (CAN bus). Therefore, if the communication line has little free time and a large amount of data needs to be transmitted through the communication line, as in the case of rewriting the control program of the electronic control unit, a very long time is required. It will take. In addition, while the control program is being rewritten, the electronic control unit that stores the control program to be rewritten is normally in a non-operational state, so other electronic control units may detect an abnormality. There was a problem.

  The problem to be solved by the present invention is that when rewriting a control program stored in one of a plurality of electronic control units connected to each other via a communication line, other electronic control units To provide a communication device for an in-vehicle electronic control device that prevents malfunction caused by detecting an abnormality and rewrites a control program at high speed.

The communication device of the on-vehicle electronic control device according to the present invention is connected to the communication line to rewrite a control program stored in a plurality of electronic control units mounted on the vehicle and connected to each other via the communication line. In a communication device of an in-vehicle electronic control device that uses an external tool, a rewrite target electronic control unit that stores a control program to be rewritten receives a write start request signal from an external tool for a first start A request signal receiving means, a self-shut time extending means for extending a preset self-shut time based on a write start request signal received by the first start request signal receiving means, and a preset self Control that rewrites the control program based on the data sent from the external tool after the shut time elapses A non-rewriteable electronic control unit other than the rewrite target electronic control unit, comprising: a program rewrite means; and a first power supply control means for turning off the power of the rewrite target electronic control unit based on an extension end signal from an external tool. A second start request signal receiving means for receiving a write start request signal from an external tool, and when the second start request signal receiving means receives the write start request signal, a preset self-shut A second power control means for turning off the power of the non-rewritable electronic control unit after a lapse of time, and after the writing start request signal from the external tool is received by the first start request signal receiving means , when the ignition switch is not turned off within a predetermined time, characterized that you and disabling the write start request signal.

  According to the communication device of the in-vehicle electronic control device of the present invention, when the rewrite target electronic control unit receives the write start request signal, the rewrite target electronic control unit extends the preset self-shut time, and sets the preset self-shut time. After the elapse, the control program is rewritten based on the data transmitted from the external tool. Then, the power is turned off based on the extension end signal from the external tool. In this case, when the non-rewrite target electronic control unit receives a write start request signal from an external tool, the non-rewrite target electronic control unit turns off the power after a preset self-shut time has elapsed. In other words, the rewriting of the control program of the rewriting target electronic control unit is performed after elapse of a preset self-shut time. Therefore, when the control program of the rewrite target electronic control unit is rewritten, the power supply of the non-rewrite target electronic control unit is already turned off. The communication line is stopped and the communication line can be used exclusively for data transmission between the external tool and the electronic control unit to be rewritten, and malfunction caused by the abnormality being detected by the electronic control unit to be rewritten can be prevented. At the same time, the control program can be rewritten at high speed.

  According to the communication device of the in-vehicle electronic control device of the present invention, if the ignition switch is not turned off within a predetermined time after the write start request signal is received from the external tool, it is determined as abnormal and the write start request signal Is invalid. Accordingly, it is possible to prevent the self-shut time of the electronic control unit to be rewritten from being unnecessarily extended when an abnormality occurs.

  In addition, the communication device of the on-vehicle electronic control device according to the present invention is configured so that the first power control means rewrites data when no data is transmitted from an external tool within a specified time after the preset self-shut time elapses. The target electronic control unit is turned off.

  According to the communication device of the on-vehicle electronic control device of the present invention, when data is not transmitted from the external tool within a specified time after the elapse of a preset self-shut time, it is determined as abnormal and the power is turned off. . Therefore, it is possible to prevent the power source of the electronic control unit to be rewritten from being turned on unnecessarily when an abnormality occurs.

  According to the present invention, when the control program of the rewrite target electronic control unit is rewritten, the power supply of the non-rewrite target electronic control unit is already turned off. The transmission of the result is stopped, and the communication line can be used exclusively for data transmission between the external tool and the electronic control unit to be rewritten. Accordingly, it is possible to prevent malfunction caused by the abnormality being detected by the non-rewritable electronic control unit, and it is possible to rewrite the control program at high speed.

  Further, according to the present invention, if the ignition switch is not turned off within a predetermined time after the write start request signal is received from the external tool, it is determined as abnormal and the write start request signal is invalidated. Accordingly, it is possible to prevent the self-shut time of the electronic control unit to be rewritten from being unnecessarily extended when an abnormality occurs.

  Further, according to the present invention, if data is not transmitted from the external tool within a specified time after the preset self-shut time has elapsed, it is determined that there is an abnormality and the power is turned off. Therefore, it is possible to prevent the power source of the electronic control unit to be rewritten from being turned on unnecessarily when an abnormality occurs.

  Hereinafter, rewriting of a control program performed using the communication device of the in-vehicle electronic control unit according to the embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a diagram illustrating a state in which an electronic control unit that rewrites a control program using a communication device of an in-vehicle electronic control unit according to an embodiment and other electronic control units are connected via a communication line. . That is, an engine electronic control unit (engine ECU) 10, an automatic transmission electronic control unit (AT / ECU) 12, and an anti-lock brake electronic control unit (ABS / ECU) 14 mounted on the vehicle are connected to a communication line (CAN bus). 18 is connected. FIG. 1 shows a state in which an external tool 20 connected to the communication line 18 is connected when the control program stored in each electronic control unit 10, 12, 14 is rewritten.

  Here, the engine ECU 10 controls the engine output and the like based on a control program stored in the storage unit 10a. The AT / ECU controls the automatic transmission based on a control program stored in the storage unit 12a. Further, the ABS / ECU 14 controls the anti-lock brake device based on a control program stored in the storage unit 14a.

  In addition, when the ignition switch (IG / SW) 22 is turned on, power is supplied to the electronic control units 10, 12, and 14, and the electronic control units 10, 12, and 14 operate. It becomes a state. When each of the electronic control units 10, 12, and 14 is in an operating state, predetermined data is communicated between the electronic control units 10, 12, and 14 at a constant period. For example, the engine ECU 10 transmits the engine speed to the AT / ECU 12 and the ABS / ECU 14 at a predetermined cycle. The ABS / ECU 14 transmits the vehicle speed to the engine ECU 10 at a predetermined cycle.

  In addition, the electronic control units 10, 12, and 14 are provided with self-shut control units 10b, 12b, and 14b, respectively. Here, the self-shut is not shut off when the IG • SW 22 is turned off, but is set in advance after the IG · SW 22 is turned off. A function to shut off after the self-shutdown time has elapsed.

  Next, rewriting of the control program stored in the electronic control unit will be described with reference to the flowchart shown in FIG. In the following description, a case where the control program stored in the engine ECU 10 is rewritten will be described as an example. In this description, the engine ECU 10 is described as a node A (rewrite target electronic control unit), and the AT / ECU 12 is described as a node B (non-rewrite target electronic control unit). The ABS / ECU 14 (non-rewriting target electronic control unit) performs the same operation as that of the node B, and thus the description thereof is omitted.

  First, the external tool 20 transmits a write start request to the node A and the node B with the IG · SW 22 turned on (step S10). Note that a write start request transmitted to the node A and the node B is used as a self-shut command. When a write start request is transmitted, a message such as “Turn off IG / SW.” Is displayed on the display unit (not shown) of the external tool 20, and the operator turns off the IG / SW 22 according to this message. To.

  In the node A, when the write start request transmitted by the external tool 20 is received (step S20), it is determined whether or not the IG / SW 22 is turned off (step S21). After receiving the start request, it is determined whether or not a predetermined time has passed (step S22). If the predetermined time has passed, the received write start request is invalidated (step S23). That is, after the write start request is received, if the IG · SW 22 is not turned off within a predetermined time, the write start request is invalidated as an abnormal state.

  If the IG / SW 22 is turned off within a predetermined time after receiving the write start request (step S21), the preset self-shut time is extended (step S24). That is, in the node A, the self-shut time is extended until the extension end command is received from the external tool 20. In this case, even after the IG • SW 22 is turned off, the supply of power from the power supply 24 is continued under the control of the self-shut control unit 10b (first power supply control means).

  The external tool 20 transmits a control program for rewriting to the node A when the IG / SW 22 is turned off and then a preset self-shut time elapses (step S11). Then, after the transmission of the control program is completed, an extension end command is transmitted to the node A (step S12).

  In the node B, when a write start request (self-shut extension command) is received from the external tool 20 (step S30), whether or not a preset self-shut time has elapsed after the IG / SW 22 is turned off. A determination is made (step S31), and when the self-shut time has elapsed, the supply of power from the power source 24 is cut off under the control of the self-shut control unit 12b (second power control means).

  The node A receives a rewrite control program transmitted by the external tool 20 after the preset self-shut time has elapsed after the IG / SW 22 is turned off (step S25). Based on the above, the control program stored in the storage unit 10a is rewritten. In addition, when data is not transmitted from the external tool 20 within a designated time after the preset self-shut time has elapsed, the supply of power from the power source 24 is cut off under the control of the self-shut control unit 10b. .

  When the extension end command transmitted by the external tool 20 is received (step S26), the supply of power from the power source 24 is cut off under the control of the self-shut control unit 10b (step S27). When transmission of the control program to the node A is completed, each node returns to a normal operation state by turning the IG • SW 22 off once and then on again.

  In the rewriting of the control program using the communication device of the in-vehicle electronic control device according to this embodiment, when the control program of the rewrite target electronic control unit is rewritten, the power of the non-rewrite target electronic control unit is already turned off. Therefore, the transmission of the self-diagnosis and the self-diagnosis result in the non-rewrite target electronic control unit is stopped, and the communication line can be exclusively used for data transmission between the external tool and the rewrite target electronic control unit. . Accordingly, it is possible to prevent malfunction caused by the abnormality being detected by the non-rewritable electronic control unit, and it is possible to rewrite the control program at high speed. In addition, since the extension end command transmitted by the external tool is transmitted after the rewrite control program is completely transmitted, the rewrite of the control program can be reliably completed.

  If the ignition switch is not turned off within a predetermined time after the write start request signal is received from the external tool, it is determined that there is an abnormality and the write start request signal is invalidated. Accordingly, it is possible to prevent the self-shut time of the electronic control unit to be rewritten from being unnecessarily extended when an abnormality occurs. Further, if data is not transmitted from the external tool within a specified time after the preset self-shut time has elapsed, it is determined that there is an abnormality and the power is turned off. Therefore, it is possible to prevent the power source of the electronic control unit to be rewritten from being turned on unnecessarily when an abnormality occurs.

  In addition, when a large number of electronic control units are mounted on a vehicle, it is possible to quickly rewrite the control program for each electronic control unit, and it is possible to reduce restrictions on production line process design. . In addition, even when the control program needs to be rewritten in the market, the rewriting time can be shortened and the trouble countermeasure cost can be reduced.

It is a block diagram which shows the electronic control unit, communication line, and external tool which concern on embodiment of this invention. It is a flowchart for demonstrating the rewriting method of the control program of the vehicle-mounted electronic control unit which concerns on embodiment of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Engine ECU, 12 ... AT * ECU, 14 ... ABS / ECU, 10b, 12b, 14b ... Self shut control part, 18 ... Communication line, 20 ... External tool, 22 ... IG * SW, 24 ... Power supply.

Claims (2)

Communication of an in-vehicle electronic control device that rewrites a control program stored in a plurality of electronic control units mounted on a vehicle and connected to each other via a communication line using an external tool connected to the communication line In the device
The electronic control unit to be rewritten, in which the control program to be rewritten is stored,
First start request signal receiving means for receiving a write start request signal from the external tool;
Self-shut time extending means for extending a preset self-shut time based on a write start request signal received by the first start request signal receiving means;
Control program rewriting means for rewriting a control program based on data transmitted from the external tool after the preset self-shut time has elapsed,
First power control means for turning off the power of the electronic control unit to be rewritten based on an extension end signal from the external tool,
Non-rewrite target electronic control units other than the rewrite target electronic control unit are:
Second start request signal receiving means for receiving a write start request signal from the external tool;
Second power control for turning off the power of the non-rewritable electronic control unit after elapse of the preset self-shut time when the write start request signal is received by the second start request signal receiving means and means,
After the write-start request signal from the external tool is received by the first start request signal receiving means, when the ignition switch is not turned off within a predetermined time, that you and disabling the write start request signal A vehicle-mounted electronic control device communication device. The first power control means turns off the power of the electronic control unit to be rewritten when data is not transmitted from the external tool within a specified time after the preset self-shut time elapses. The communication device of the on-vehicle electronic control device according to claim 1 .

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