JP2013151220A - On-vehicle control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent holding data from being initialized by mistake when driving a starter, with a constitution for initializing the holding data when a battery is removed.SOLUTION: In ignition OFF, execution history data is set to nonexecution, and is written in a flash memory. When a power source reset is released by ignition ON or returning from a voltage drop when driving the starter, the execution history data is read in from the flash memory (S1). When the execution history data is not executed, a detecting signal Sb of the voltage drop is read in (S3). When it is determined that there is removal, the holding data is initialized (S5), and when it is determined that there is no removal, the holding data is read out of the flash memory (S7). The execution finish and the removal existence/nonexistence are set in the execution history data, and are read in the flash memory (S6 and S7), and the detecting signal Sb is reset (S13). When the execution history data is already executed (S2: NO), reading-in processing of the detecting signal Sb and battery removal determining processing are not executed.

Description

  The present invention relates to an in-vehicle control device that initializes retained data in response to removal of a battery.

  FIG. 6 shows a configuration related to a microcomputer and a power supply IC of a conventional in-vehicle control device disclosed in Patent Document 1 and the like. An electronic control device 1 (hereinafter referred to as ECU 1) that controls an engine of a vehicle turns on a main relay 4 by a drive circuit 3 when an ignition switch 2 is turned on. The main power supply circuit 5 generates a main power supply voltage VOM from the voltage VB supplied from the battery 6 through the contact of the main relay 4 and supplies the main power supply voltage VOM to the main processing unit 8 including the CPU of the microcomputer 7.

  In addition to the main processing unit 8 that operates at the main power supply voltage VOM (5 V), the microcomputer 7 also includes a low voltage circuit processing unit that operates at the sub power supply voltage VOS (3 V / 3.3 V), such as the RAM 9. Yes. Therefore, the sub power supply circuit 10 generates the sub power supply voltage VOS1 (3.3 V) from the voltage VB supplied from the battery 6 through the contact of the main relay 4 and supplies it to the low voltage circuit processing unit including the RAM 9.

  The RAM 9 stores diagnosis data, learning data of various sensors, and the like, and it is necessary to keep these data while the ignition switch 2 is off. The sub power supply circuit 11 generates a sub power supply voltage VOS2 (3 V) based on the voltage VBATT supplied from the battery 6 through a dedicated wiring that is always connected. While the sub power supply circuit 10 is in constant voltage output operation, the sub power supply circuit 11 stops the output operation.

  In order to retain the data stored in the RAM 9, the sub power supply circuit 11 must be operated even when the vehicle is not used. For this reason, the dedicated wiring always connected is required. In addition, since a large number of ECUs including the ECU 1 are mounted on the vehicle, if the dark current for memory backup in each ECU increases, the battery may run out. Therefore, a dedicated wiring is eliminated and a nonvolatile memory such as a flash memory or an EEPROM is used instead of the conventional RAM 9.

  In recent years, laws and regulations that require the installation of an OBD (On Board Diagnosis System), which is an in-vehicle failure diagnosis device, have been advanced. The OBD is a device that executes a predetermined diagnosis process and stores and holds the content of the failure when it is determined that the failure has occurred, and lights a warning lamp to notify the driver. Examples of diagnostic items include catalyst deterioration, engine misfire, oxygen sensor or air-fuel ratio sensor failure, exhaust gas recirculation system (EGR) failure, and the like. The stored data includes past failure diagnosis execution history data, engine related data at the time of failure, and the like.

  When the vehicle is brought to a dealer or a repair shop because the warning lamp is turned on, a failure diagnosis tool is usually connected to the ECU 1 for more detailed data analysis. When repairs such as parts replacement are performed, the diagnosis data and learning data of the nonvolatile memory are initialized using the failure diagnosis tool. However, for situations where a failure diagnosis tool cannot be used or for vehicles not equipped with an OBD, as a simpler initialization method, the battery 6 is removed from the ECU 1 and reconnected, and then the ignition switch is set to the IGON position. A method of initializing data stored in the nonvolatile memory at a time (or when IGOFF is subsequently set) is used.

JP 2006-105001 A

  The vehicle-mounted control apparatus mentioned above has detected that the battery was removed by comparing a battery voltage with a threshold value. However, a battery that has been deteriorated or a battery that is used in a very low temperature environment such as below freezing has an increased internal resistance, and when the starter is driven, there is a possibility that the voltage is greatly reduced, and it is erroneously determined that the battery has been removed. If a misjudgment occurs, it has the serious consequence that the data to be retained is initialized.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an in-vehicle control device capable of avoiding erroneous initialization of retained data when a starter is driven.

  The vehicle-mounted control apparatus according to the first aspect is mounted on a vehicle including an ignition switch, a power supply relay that opens and closes a power supply path from the battery, and a starter that starts the engine. The in-vehicle control device includes a rewritable nonvolatile memory, a battery detachment detection circuit, and a control unit. The battery detachment detection circuit outputs a detection signal indicating that the battery has been removed on condition that the voltage from the battery has fallen below the threshold, and the battery is removed on condition that the reset signal has been input. A detection signal indicating that the signal has not been output is output.

  The control means executes an initial process prior to driving the starter at the time of rising from the power reset when the ignition switch is turned on while the battery is connected or a voltage drop caused by driving the starter. . Further, when the ignition switch is turned off, the power supply relay is turned off after the shutdown process is executed. The execution history data is execution history information indicating the execution status of the detection signal reading process and the battery detachment determination process performed by the control means, and has the data content not executed or executed. This execution history data is stored in a nonvolatile memory. The retained data is data that is always stored in the nonvolatile memory even when the ignition switch is off, and is initialized when the battery is removed.

  The control means sets the execution history data to non-executed in the shutdown process and writes it to the nonvolatile memory. The control means reads execution history data from the nonvolatile memory in the initial process. Here, the case where the read execution history data is set to non-execution is when the ignition switch is turned on, and when the detection signal is not read and the starter is not driven since the previous ignition off. is there.

  In this case, since the reading process of the detection signal and the determination process of whether or not the battery has been removed (battery removal) should be executed during the period when the ignition switch is off, these processes are executed to execute the execution history. Set data as executed and write to non-volatile memory. When it is determined that the battery has been removed, the retained data is initialized. Thereby, even when there is no failure diagnosis tool (dedicated tool), the retained data can be easily initialized. Since the detection signal is used for the determination, a reset signal is output to the battery removal detection circuit in preparation for the next battery removal.

  On the other hand, when the read execution history data is set to executed, the ignition switch is turned on, the detection signal reading process and the battery removal determination process are executed, and the ignition switch is not turned off. However, this is a case where a power reset occurs. That is, an abnormal voltage drop occurs due to starter driving or the like. In this case, there is a high probability that the battery detachment detection circuit outputs a detection signal indicating battery detachment even though the battery is not removed. Therefore, the control means outputs a reset signal to the battery detachment detection circuit without executing the detection signal reading process and the battery detachment determination process.

  Such control can avoid erroneous determination that the battery has been removed even when the battery voltage drops when the starter is driven and the battery removal detection circuit outputs a detection signal indicating battery removal. As a result, it is possible to prevent the stored data from being erroneously initialized even if the battery is not removed.

  According to the means described in claim 2, in the initial process, the control means also sets a determination result as to whether or not the battery is removed when the execution history data is set to executed and written to the nonvolatile memory. Write. In the initial process, when the execution history data read from the non-volatile memory has been executed and the determination result indicates that the battery has been removed, that is, the start-up period of the first ignition switch after the battery has been removed. If an abnormal voltage reset occurs due to driving or the like, the held data is reinitialized. Thereby, it is possible to reliably prevent the retained data once initialized from becoming unstable due to a voltage drop.

  According to the means described in claim 3, the control means stores the retained data in the volatile memory and writes it in the nonvolatile memory in the shutdown process. In the initial process, the control means initializes the retained data for the retained data stored in the volatile memory. Further, when the execution history data read from the nonvolatile memory is a result of determination that the execution history data is not executed and the battery is not removed, the retained data is read from the nonvolatile memory to the volatile memory. Thereby, the processing speed can be increased. Furthermore, even when the execution history data read from the nonvolatile memory is a result of determination that the battery has not been removed, the retained data is read again from the nonvolatile memory to the volatile memory. As a result, it is possible to reliably prevent the held data once read from becoming unstable due to a voltage drop.

  According to a fourth aspect of the present invention, there is provided a starter control circuit for driving the starter when a starter drive signal is inputted. When the start command is input, the control means outputs a starter drive signal after the initial process is completed. As a result, it is possible to prevent the voltage from being lowered due to the starter being driven before the initial process is completed.

  According to the means described in claim 5, when the start command is input, the starter is driven after waiting for at least the processing time of the initial process. As a result, it is possible to prevent the voltage from being lowered due to the starter being driven before the initial process is completed.

  According to the means described in claim 6, the first power line connected to the positive terminal of the battery via the ignition switch and the normally open contact of the power supply relay between the vehicle-mounted control device and the battery. A second power supply line connected to the positive terminal of the battery and a third power supply line connected to the positive terminal of the battery via the coil of the power supply relay are provided. Since the retained data is stored in the nonvolatile memory, it is not necessary to provide a dedicated wiring for directly connecting the in-vehicle control device and the battery, and the dark current can be reduced.

  According to the means described in claim 7, the battery detachment detection circuit detects that the battery has been removed on condition that the highest voltage among the voltages of the first to third power supply lines is equal to or lower than the threshold value. The detection signal shown is output. Thereby, even when the dedicated wiring is not provided, it is possible to detect battery disconnection.

The block diagram of the electronic control system which shows the 1st Embodiment of this invention Initial processing flowchart Flow chart of shutdown process Timing chart when battery voltage drops due to starter drive FIG. 1 equivalent diagram showing a second embodiment of the present invention 1 equivalent diagram showing the prior art

In each embodiment, substantially the same parts are denoted by the same reference numerals and description thereof is omitted.
(First embodiment)
Hereinafter, a first embodiment will be described with reference to FIGS. 1 to 4. An electronic control device 21 (hereinafter referred to as ECU 21) shown in FIG. 1 is an in-vehicle control device that controls an engine (internal combustion engine). The vehicle includes a battery 22, an ignition switch 23, a main relay 24 (power supply relay) that opens and closes a power supply path (power line 29) from the battery 22, a starter 25 (starter motor) that cranks the engine, and a starter relay. 26 and a starter switch 27 are provided. When the coil 26 b of the starter relay 26 is energized, the contact 26 a is closed and power is supplied from the battery 22 to the starter 25.

  Terminals 21a, 21b, and 21c of the ECU 21 are power supply terminals provided on the power supply lines 28, 29, and 30, respectively. The first power supply line 28 is connected to the positive terminal of the battery 22 via the ignition switch 23. The second power supply line 29 is connected to the positive terminal of the battery 22 via the normally open contact 24 a of the main relay 24. The third power line 30 is connected to the positive terminal of the battery 22 through the coil 24 b of the main relay 24. In the following description, the voltages of these power supply lines 28, 29, and 30 are VB1, VB2, and VB3, respectively, and the voltage of the battery 22 is VB. In order to suppress a surge voltage generated by a load dump or the like, a diode or a Zener diode (not shown) is connected between each power line and the ground as necessary.

  The ECU 21 includes a power supply IC 31, a microcomputer 32, and a starter control circuit 33. The power supply IC 31 generates a main power supply voltage VOM (5 V) and a sub power supply voltage VOS (3.3 V) based on the voltage VB2 of the power supply line 29 and supplies it to the microcomputer 32. Further, when the ignition switch 23 is turned on, the main relay 24 is turned on. Further, a detection signal Sb indicating whether or not the battery 22 is removed from the ECU 21 is output to the microcomputer 32.

  The microcomputer 32 includes a main processing unit 34 (control means) that operates at a main power supply voltage VOM, mainly a CPU, a RAM 35 (volatile memory), and a flash memory (nonvolatile memory), and operates at a sub power supply voltage VOS. A circuit processing unit is provided. The flash memory stores retention data such as diagnostic data and learning data and stores the flash memory 36 to be subjected to initialization processing, which will be described later, the engine control program, the initial value of the retention data, and the like. It consists of a flash memory (not shown) that is not the target.

  In the power supply IC 31, the relay control circuit 37 turns on the MOSFET 38 and drives the main relay 24 on when the voltage VB1 of the power supply line 28 rises. Even after the ignition switch 23 is turned off, the relay control circuit 37 continues to turn on the MOSFET 38 while the H level power supply maintenance signal Sh is input from the microcomputer 32.

  The main power supply circuit 39 inputs the voltage VB2 of the power supply line 29 and generates the main power supply voltage VOM. The configuration is a series regulator including a reference voltage generation circuit 40, an operational amplifier 41, a transistor 42, and voltage dividing resistors 43a and 43b (voltage detection circuit 43). The sub power supply circuit 44 also receives the voltage VB2 of the power supply line 29 and generates the sub power supply voltage VOS. The configuration is a series regulator including a reference voltage generation circuit 40, an operational amplifier 45, a transistor 46, and voltage dividing resistors 47a and 47b (voltage detection circuit 47).

  The battery disconnection detection circuit 48 detects that the battery has been removed when the highest voltage among the voltages VB1, VB2, and VB3 of the power supply lines 28, 29, and 30 drops below the threshold and then exceeds the threshold again. An H level detection signal Sb is output. If the battery 22 is connected, one of the voltages VB1, VB2, and VB3 is the battery voltage VB regardless of the state of the ignition switch 23. When the reset signal Sr is input from the microcomputer 32, the battery removal detection circuit 48 outputs an L level detection signal Sb indicating that the battery is not removed.

  Although not shown, a power-on reset circuit is provided that outputs a power reset signal to the microcomputer 32 when the main power supply voltage VOM drops below a threshold value. The threshold value used by the battery detachment detection circuit 48 is set to be equal to or lower than the threshold value used by the power-on reset circuit. Therefore, when the battery detachment detection circuit 48 outputs the H level detection signal Sb due to a decrease in the battery voltage, the microcomputer 32 is always reset. Instead of the power-on reset circuit, the battery detachment detection circuit 48 may have a power-on reset function.

  Next, the operation of the present embodiment will be described with reference to FIGS. The ECU 21 of the vehicle stores retained data such as diagnostic data and learning data in the flash memory 36 so as to contribute to the identification of the failure state. The retained data is always retained regardless of the state of the ignition switch 23 unless initialization is performed. When a failure occurs in the vehicle and repair is performed at a dealer or a repair shop, the stored data stored in the flash memory 36 is initialized.

  The initialization of retained data is a process of setting an initial value stored in a flash memory or ROM (not shown) that is not an initialization target as retained data, and the retained data is stored in the flash memory 36. Written. The ECU 21 of the present embodiment uses a method of initializing by turning on the ignition switch 23 after removing the battery 22 from the ECU 21 and reconnecting it in addition to the method of initializing using the failure diagnosis tool (dedicated tool). can do.

  FIG. 2 shows an initial process executed by the main processing unit 34 of the microcomputer 32 before the starter 25 is driven when the power reset is released. The voltage VB2 of the power supply line 29 and hence the main power supply voltage VOM are lowered and the power supply is reset when the ignition switch 23 is turned off and when the battery voltage VB is lowered by driving the starter 25 or the like. The battery 22 is removed while the ignition switch 23 is turned off. FIG. 3 shows a shutdown process that is finally executed after the main processing unit 34 performs various processes that should be performed before the power is shut off when the ignition switch 23 is turned off. When the battery voltage VB is lowered due to driving of the starter 25 and the power supply is reset, the shutdown process is not executed.

  FIG. 4 is a timing chart in the case where the battery voltage VB is lowered by driving the starter 25, the battery disconnection detection circuit 48 outputs an H level detection signal Sb indicating battery disconnection, and the microcomputer 32 is reset to a power source. is there. The main processing unit 34 reads stored data such as diagnostic data and learning data from the flash memory 36 to the RAM 35 in the initial processing. Thereafter, the main processing unit 34 updates data for the data held in the RAM 35, and writes the data held in the RAM 35 to the flash memory 36 in the shutdown process.

  In order to prevent erroneous determination that the battery is disconnected due to the starter 25 being driven, the main processing unit 34 uses execution history data. The execution history data is an execution status (unexecuted / executed) indicating whether or not the detection signal Sb reading process and the battery detachment determination process based on the read detection signal Sb have been executed since the ignition switch 23 was previously turned off. Data) indicating the determination result of whether or not the battery 22 has been removed (with / without disconnection). This execution history data is stored in the flash memory 36.

  In the shutdown process, the main processing unit 34 sets unexecuted execution history data in the RAM 35 (step T1) and writes it in the flash memory 36 (step T2). That is, when the ignition switch 23 is turned off (time t1, t4, t9), the execution history data is always set to non-execution. Thereafter, the main processing unit 34 writes the retained data to the flash memory 36 and saves it (step T3), sets the power maintenance signal Sh to L level, and shuts off the main relay 24.

  When the initial processing is started (time t2, t3, t7, t8, t10, t11), the main processing unit 34 reads execution history data from the flash memory 36 (step S1), and whether or not the execution history data is unexecuted. Is determined (step S2). As will be described later, when the initial process is executed, the execution history data is maintained to be executed during the period from when the ignition switch 23 is turned off to when the shutdown process is executed (steps S6 and S7).

  The case where the execution history data is not executed (YES) is the initial processing for the first time since the ignition switch 23 was turned off the last time, in other words, the rise (time t2, t7, This is a time t10) that is not a rise (time t3, t8, t11) from a power reset due to a temporary drop in the battery voltage VB due to driving of the starter 25 or the like.

  In this case, the detection signal Sb is read (step S3), and it is determined whether or not battery removal is detected (step S4). When the detection signal Sb is at the H level, it is determined that the battery has been removed (YES), and the stored data stored in the RAM 35 is initialized (step S5). At this time, the stored data that has been initialized may be immediately written to the flash memory 36. However, if the writing time becomes long, the starter 25 may be delayed in starting. Therefore, as described above, the data is written in the flash memory 36 at step T3 of the shutdown process. Thereafter, execution history data that has been executed and has been set off is set in the RAM 35 (step S6), and is written in the flash memory 36 (step S9).

  On the other hand, when the detection signal Sb is at the L level, it is determined that the battery is not removed (NO), and the retained data is read from the flash memory 36 to the RAM 35 (step S7). Thereafter, execution history data that has been executed and is not detached is set in the RAM 35 (step S8), and is written in the flash memory 36 (step S9). Thereafter, the main processing unit 34 outputs a reset signal Sr in preparation for the next battery removal (step S13).

  The case where the execution history data is already executed (NO) at the determination in step S2 is that at least one initial process has been executed since the ignition switch 23 was turned off last time, and the ignition switch 23 is turned off. This is a case where the power supply is reset without being reset (time t3, t8, t11). The detection signal Sb in this case has a high probability of being at the H level (battery disconnected) due to a decrease in the battery voltage even though the battery 22 is not removed. That is, the detection signal Sb does not reflect a true battery removal state.

  Accordingly, the main processing unit 34 does not execute the reading process of the detection signal Sb and the battery detachment determination process based on the read detection signal Sb. Also, the execution history data is not changed. Further, since there is a possibility that the retained data in the RAM 35 is indefinite due to the power reset, the resetting is performed. That is, it is determined whether or not the execution history data is out (step S10). If the execution history data is out (YES), the retained data stored in the RAM 35 is initialized as in step S5 (step S11). If there is no disconnection (NO), the stored data is read from the flash memory 36 to the RAM 35 as in step S7 (step S12). The main processing unit 34 outputs a reset signal Sr in preparation for the next battery removal (step S13).

  In order to start the engine, the driver turns on the ignition switch 23 and turns on the starter switch 27 while stepping on the brake. If the time from the ON operation of the ignition switch 23 to the ON operation of the starter switch 27 is short, there may be a situation where the initial process is not in time. Therefore, when a start command is input from the starter switch 27, the main processing unit 34 outputs a starter drive signal after the initial process is completed. The starter control circuit 33 energizes the coil 26 b of the starter relay 26 when a starter drive signal is input from the microcomputer 32. As a result, it is possible to prevent the voltage drop due to the starter 25 being driven before the initial process is completed.

  As described above, the microcomputer 32 according to the present embodiment includes the flash memory 36 and has a configuration in which stored data that needs to be constantly stored is stored in the flash memory 36. Further, the battery detachment detection circuit 48 is configured to output the detection signal Sb based on the highest voltage among the voltages VB1, VB2, and VB3 of the power supply lines 28, 29, and 30. With such a configuration, a dedicated wiring for directly connecting the ECU 21 and the battery 22 becomes unnecessary, and a dark current for data backup can be reduced.

  The main processing unit 34 newly introduces execution history data, and reads the execution history data from the flash memory 36 in the initial process before driving the starter 25. Depending on whether the execution history data has not been executed or has been executed, it can be determined whether the rising is normal due to the ignition being turned on, or whether the rising is abnormal due to a decrease in the battery voltage VB. In the latter determination, the main processing unit 34 does not execute the detection signal Sb reading process and the battery removal determination process. Therefore, even if the battery voltage VB drops below the threshold value by driving the starter 25, it is possible to prevent the stored data from being erroneously determined to be out of battery and being initialized.

  In the initial process, the main processing unit 34 also writes the determination result of battery detachment when the execution history data is set to executed and written to the flash memory 36. In the initial process, when the execution history data read from the flash memory 36 has been executed, the re-initialization of the holding data / re-reading of the holding data is executed according to the determination result (existence / non-existence). Thereby, it is possible to reliably prevent the retained data from becoming indefinite due to the decrease in the battery voltage VB.

  The main processing unit 34 stores the retained data in the RAM 35 and saves it in the flash memory 36 in the shutdown process. According to this processing sequence, it is only necessary to initialize the retained data, update the retained data, etc. to the RAM 35, so that the processing speed can be increased.

(Second Embodiment)
An electronic control device 51 (ECU 51) shown in FIG. 5 is configured in the same manner as the ECU 21 shown in FIG. 1 except that a delay circuit 52 is provided instead of the starter control circuit 33. The ECU 51 does not have a function of directly controlling the drive timing of the starter 25. Therefore, the delay circuit 52 delays the start command from the starter switch 27 and energizes the coil 26 b of the starter relay 26. The delay time at this time is set to be longer than the time required for the initial process. Also according to the present embodiment, the same operations and effects as those of the first embodiment can be obtained.

(Other embodiments)
As mentioned above, although preferred embodiment of this invention was described, this invention is not limited to embodiment mentioned above, A various deformation | transformation and expansion | extension can be performed within the range which does not deviate from the summary of invention.

  The execution history data only needs to include at least the execution status (not executed / executed), and does not need to include the determination result (missed / not missed). That is, the executed history data is set in the RAM 35 in steps S6 and S8 shown in FIG. 2, and if NO is determined in step S2, the processes in steps S10 to S12 may be skipped and the process proceeds to step S13. However, if NO is determined in step S2, the retained data may become indefinite, so it is preferable to perform resetting processing or error processing separately.

  The main processing unit 34 initializes the retained data in the RAM 35 in the initial process, or reads the retained data from the flash memory 36 into the RAM 35, and writes the retained data in the RAM 35 into the flash memory 36 in the shutdown process. However, the stored data stored in the flash memory 36 may be directly rewritten without storing the stored data in the RAM 35. In this case, the retained data stored in the flash memory 36 in steps S5 and S11 is initialized, and the processes in steps S7, S12, and T3 are unnecessary.

The rewritable nonvolatile memory referred to in the present invention is not limited to one memory chip. The non-volatile memory that stores the execution history data and the non-volatile memory that stores the retained data may be different memory chips or different memory areas. The rewritable nonvolatile memory is not limited to the flash memory 36, and may be, for example, an EEPROM.
The power supply relay referred to in the present invention broadly means switch means including a switch using a semiconductor switch.

  In the drawings, 21 and 51 are electronic control devices (vehicle-mounted control devices), 22 is a battery, 23 is an ignition switch, 24 is a main relay (power supply relay), 24a is a normally open contact, 24b is a coil, 25 is a starter, 28, 29 and 30 are first, second and third power lines, 33 is a starter control circuit, 34 is a main processing unit (control means), 35 is RAM (volatile memory), and 36 is flash memory (rewritable). (Nonvolatile memory), 48 is a battery disconnection detection circuit, and 52 is a delay circuit.

Claims (7)

In an in-vehicle control device mounted on a vehicle equipped with an ignition switch, a relay for power supply for opening and closing a power supply path from a battery, and a starter for starting an engine,
Rewritable nonvolatile memory,
Outputs a detection signal indicating that the battery has been removed on the condition that the voltage from the battery has fallen below the threshold value, and indicates that the battery has not been removed on the condition that the reset signal has been input A battery disconnection detection circuit that outputs a signal;
When the ignition switch is turned off, execution history data relating to the execution status of the detection signal reading process and the battery detachment determination process is set to unexecuted and written to the nonvolatile memory, and then the power supply relay When the shutdown process is executed to turn off the power supply, the execution history data is read from the nonvolatile memory before the starter is driven, and the read execution history data is set to non-execution. In this case, the detection signal reading process and the battery detachment determination process are executed to set the execution history data as executed and written to the nonvolatile memory. When it is determined that the battery is removed, the nonvolatile memory Initialize the stored data that is stored in the memory and is held at all times. When a set signal is output and the read execution history data is set to executed, a reset signal is output to the battery removal detection circuit without executing the detection signal reading process and the battery removal determination process. The vehicle-mounted control apparatus characterized by including the control means which performs the initial process which outputs.   In the initial process, when the execution history data is set to executed and written to the nonvolatile memory in the initial process, the control means also writes a determination result as to whether or not a battery has been removed, from the nonvolatile memory. The in-vehicle control device according to claim 1, wherein when the read execution history data is a result of determination that the execution has been completed and the battery has been removed, the retained data is initialized. With volatile memory,
The control means writes retained data stored in the volatile memory to the nonvolatile memory in the shutdown process, and retains initialization of the retained data stored in the volatile memory in the initial process. The execution history data read from the non-volatile memory is executed and the execution history data read from the non-volatile memory is executed and the execution history data read from the non-volatile memory is not executed and the battery is not removed. The in-vehicle control device according to claim 2, wherein when the determination result indicates that the battery is not removed, the retained data stored in the nonvolatile memory is read out to the volatile memory. A starter control circuit for driving the starter when a starter drive signal is input;
4. The in-vehicle control device according to claim 1, wherein when the start command is input, the control means outputs the starter drive signal after the initial process is completed.   4. The in-vehicle control device according to claim 1, further comprising a delay circuit that enables driving of the starter after waiting for at least a processing time of the initial processing when a start command is input. .   A first power line connected between the battery and the positive terminal of the battery via the ignition switch, and a positive terminal of the battery via a normally open contact of the power supply relay. 6. The third power supply line connected to the positive terminal of the battery through a second power supply line and a coil of the power supply relay is provided. In-vehicle control device.   The battery detachment detection circuit outputs a detection signal indicating that the battery has been removed on condition that the highest voltage among the voltages of the first to third power supply lines is equal to or lower than a threshold value. The in-vehicle control device according to claim 6.

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