Control device and input / output interface unit

Abstract

When the power supply is started, the timer circuit switches the second switching switch and the third switching switch to the pulse output unit for a certain period of time, and causes the pulse output unit to output code pulses to the second communication line. When the power supply is started, the input / output control unit switches the first switching switch to the first terminal for a certain period of time, determines whether the code indicated by the code pulses received from the first terminal is a regular code, and cuts off the power supplied from the first power supply line to the second power supply line when the code is not the regular code.

Description

Technical Field

[0001] The present invention relates to a control device and an input / output interface unit. Background Art

[0002] In a substrate unit for controlling an electrical device mounted on a vehicle, an input unit or an output unit, a control circuit, a connector for connecting the electrical device, etc. are usually mounted on a substrate (for example, Patent Document 1). Vehicles have various specifications, and the number of electrical devices to be mounted varies depending on the specifications. Therefore, it is necessary to design a substrate for each specification of the substrate unit.

[0003] Therefore, in order to prevent waste, it is considered to design a part with different specifications on a separate substrate. Specifically, a control circuit (control unit) and an input unit or an output unit are provided on separate substrates, and the substrate on which the control circuit is mounted (hereinafter, referred to as a control device) is connected to the substrate on which an input unit or an output unit matching the specification is mounted (hereinafter, referred to as an input / output interface unit).

[0004] However, in this case, there is a problem that an unauthorized device is connected to the input / output interface unit via a connection unit provided in the control device, resulting in the possibility of unauthorized access to the control device.

[0005] Citation List

[0006] Patent Document

[0007] Patent Document 1: JP-2014-187123-A. Summary of the Invention

[0008] The present invention is made in view of the above circumstances, and an object of the present invention is to provide a control device and an input / output interface unit that can prevent unauthorized access to the control device when an unauthorized device is connected to the control device.

[0009] To achieve the above object, the control device and the input / output interface unit according to the present invention are characterized as follows.

[0010] A control device according to the present disclosure controls an input / output interface unit, and the input / output interface unit includes an input / output circuit that is one of an input circuit and an output circuit for an electrical device.

[0011] The control device includes: a first power supply line to which power is supplied; a first communication line through which signals are transmitted; a first connection unit configured to connect a second power supply line and a second communication line of the input / output interface unit to the first power supply line and the first communication line; a control unit configured to control the input / output interface unit; and a first switching unit configured to switch a connection destination of the first communication line between a first terminal that receives a code pulse and a second terminal that receives or outputs a communication signal.

[0012] When starting the supply of power, the control unit switches the first switching unit to the first terminal for a certain period of time, determines whether a code indicated by the code pulse received from the first terminal is a regular code, and cuts off the power supplied from the first power supply line to the second power supply line when the code is not the regular code.

[0013] In addition, an input / output interface unit according to the present disclosure includes an input / output circuit that is one of an input circuit and an output circuit for an electrical device, and operates based on communication with a control device.

[0014] The input / output interface unit includes: a second power supply line to which power is supplied; a second communication line through which signals are transmitted; a second connection unit configured to connect a first power supply line and a first communication line of the control device to the second power supply line and the second communication line; a pulse output unit configured to output a code pulse; a second switching unit configured to switch a connection destination of the second power supply line between the pulse output unit and the input / output circuit; a third switching unit configured to switch a connection destination of the second communication line between the pulse output unit and the input / output circuit; and a timer circuit configured to switch the second switching unit and the third switching unit to the pulse output unit for a certain period of time when starting the supply of power, and cause the pulse output unit to output the code pulse to the second communication line.

[0015] The present invention has been briefly described above. In addition, details of the present invention will be described by reading aspects for implementing the following present invention (hereinafter, referred to as "embodiments") with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a block diagram showing an embodiment of a communication system according to the present invention.

[0017] Figure 2 is Figure 1 a configuration diagram of the shown area ECU and the input / output interface unit.

[0018] Figure 3 is an operation sequence diagram for representing Figure 1 the operation of the communication system shown. Detailed implementation mode

[0019] Hereinafter, specific embodiments of the present invention will be described with reference to the drawings.

[0020] Figure 1 is a block diagram showing an embodiment of the communication system 1 according to the present invention.

[0021] Figure 1 is a block diagram showing the communication system 1, in which a regional ECU 3 and an input / output interface unit 4 as control devices of the present invention are provided. The communication system 1 according to the present embodiment is installed in a vehicle. The communication system 1 includes a central ECU 2, a regional ECU 3, and an input / output interface unit 4.

[0022] The central ECU 2 is formed of a microcomputer including a memory such as a RAM and a ROM and a CPU that operates according to a program stored in the memory, and is provided in an instrument panel of a vehicle such as a car. The central ECU 2 controls the entire communication system 1.

[0023] The regional ECU 3 is provided in each region of the vehicle such as the left and right doors. The regional ECU 3 communicates with the central ECU 2 and controls the input / output interface unit 4 connected to the electrical device 5 according to an instruction from the central ECU 2.

[0024] Next, Figure 2 the detailed configurations of the above-mentioned regional ECU 3 and input / output interface unit 4 will be described.

[0025] First, the regional ECU 3 will be described. The regional ECU 3 includes first power lines L11, L12, a first communication line L13, a first connector 31 (first connection unit), an input / output control unit 32 (control unit), a first switch 33 (first switching unit), a power switch 34, and a substrate (not shown) on which these components are mounted. Electric power is supplied from the central ECU 2 to the first power lines L11, L12. The first power line L11 is supplied with the positive-side potential of the electric power, while the first power line L12 is supplied with the negative (ground) -side potential of the electric power. The first communication line L13 is a communication line for performing SPI communication with, for example, the input / output drive unit 41 of the input / output interface unit 4 (described later). In the present embodiment, the first power lines L11, L12, and the first communication line L13 are respectively formed by wiring patterns formed on the substrate.

[0026] The first connector 31 is a connector for connecting the first power supply lines L11, L12 and the first communication line L13 to the input / output interface unit 4 described later. In the present embodiment, the first connector 31 includes terminal fittings (not shown) respectively connected to the first power supply lines L11, L12 and the first communication line L13, and a connector housing (not shown) for accommodating the terminal fittings. The first connector 31 is connected to a second connector 42 provided in the input / output interface unit 4 described later.

[0027] The input / output control unit 32 is formed of a microcomputer including a memory such as a RAM and a ROM and a CPU that operates according to a program stored in the memory. The input / output control unit 32 controls the input / output drive unit 41 of the input / output interface unit 4 described later according to communication with the central ECU 2.

[0028] The first switching switch 33 is a switch for switching the connection destination of the first communication line L13 between a first terminal T1 that receives a code pulse from the input / output control unit 32 and a second terminal T2 that receives or outputs a communication signal. The switching of the first switching switch 33 is controlled by the input / output control unit 32.

[0029] In the present embodiment, the first power supply line L11 branches into two lines, and one of the two branch lines is connected to the input / output control unit 32 to supply power to the input / output control unit 32. In addition, the first connector 31 is connected to the other of the two branch lines and supplies power to the input / output interface unit 4 described later.

[0030] The power switch 34 is provided on the branch line of the first power supply line L11 that is connected to the first connector 31. When the power switch 34 is turned off, the power supplied to the input / output interface unit 4 to which the first connector 31 is connected is cut off.

[0031] Next, the input / output interface unit 4 will be described. The input / output interface unit 4 includes an input / output drive unit 41 (input / output circuit), second power supply lines L21, L22, a second communication line L23, a second connector 42 (second connection unit), a code setting unit 43, a pulse output unit 44, a second switching switch 45 (second switching unit), a third switching switch 46 (third switching unit), a timer circuit 47, and a substrate (not shown) on which these components are mounted.

[0032] The input / output drive unit 41 includes at least one of an output circuit and an input circuit for the electrical device 5. The output circuit is provided for an electrical device 5 such as a motor or a lamp that operates through an output from the area ECU 3. The output circuit has a switch that is turned on under the control of the area ECU 3 to supply power to the electrical device 5 and drives the electrical device 5.

[0033] The input circuit is provided for an electrical device 5 such as a detection switch to input status information such as ON-OFF information into the area ECU 3, generate the status information, and input it into the area ECU 3.

[0034] Power is supplied from the area ECU 3 to the second power supply lines L21 and L22. The second power supply line L21 is supplied with the positive-side potential of the power, while the second power supply line L22 is supplied with the negative (ground) - side potential of the power. The second communication line L23 is a communication line for performing SPI communication with, for example, the input / output control unit 32 of the above area ECU 3. The second power supply lines L21 and L22 and the second communication line L23 are formed by a wiring pattern formed on the substrate.

[0035] The second connector 42 is a connector for connecting the second power supply lines L21 and L22 and the second communication line L23 to the above area ECU 3. In this embodiment, the second connector 42 includes terminal fittings (not shown) respectively connected to the second power supply lines L21 and L22 and the second communication line L23, and a connector housing (not shown) for accommodating the terminal fittings. The second connector 42 is connected to the first connector 31 provided in the above area ECU 3. When the first connector 31 and the second connector 42 are connected, the first power supply line L11 and the second power supply line L21 are connected, the first power supply line L12 and the second power supply line L22 are connected, and the first communication line L13 and the second communication line L23 are connected.

[0036] The code setting unit 43 stores codes such as product numbers unique to the input / output interface unit 4. The pulse output unit 44 outputs code pulses representing the codes stored in the code setting unit 43. The second switching switch 45 is a switch for switching the connection destination of the second power supply line L21 between the pulse output unit 44 and the input / output drive unit 41. The third switching switch 46 is a switch for switching the connection destination of the second communication line L23 between the pulse output unit 44 and the input / output drive unit 41.

[0037] The timer circuit 47 operates by receiving power from the second power supply line L21. When power supply is started, the timer circuit 47 switches the second switching switch 45 and the third switching switch 46 to the pulse output unit 44 for a certain period of time, and causes the pulse output unit 44 to output code pulses to the second communication line L23.

[0038] Next, SPI communication, which is an example of communication performed by the above input / output control unit 32 and input / output drive unit 41, will be briefly described. The input / output control unit 32 and the input / output drive unit 41 are connected by a clock line, a chip selector line, an output line, and an input line. The input / output control unit 32 outputs a clock signal and a CS signal to the input / output drive unit 41 via the clock line and the chip selector (CS) line.

[0039] The input / output control unit 32 outputs a serial communication signal to the input / output drive unit 41 via the output line. When the CS signal is L (in the case of active low), the input / output drive unit 41 operates according to the clock signal and the communication signal. Specifically, serial-to-parallel conversion is performed on the serial communication signal, and the serial communication signal is output to each of a plurality of switches that supply power to a plurality of electrical devices 5, so that the output circuit constituting the input / output control unit 32 can supply power to the electrical device 5 according to the corresponding communication signal. When the input circuit constituting the input / output control unit 32 receives the communication signal, parallel-to-serial conversion is performed on the status information of each electrical device 5, and the status information is output to the input line.

[0040] That is, the input / output drive unit 41 does not need to be constituted by a microcomputer or the like that operates according to a program, but is constituted by an inexpensive serial-to-parallel conversion circuit, a parallel-to-serial conversion circuit, and the like. The first communication line L13 and the second communication line L23 include the above-mentioned clock line, chip selector line, output line, and input line, and the connection destination of the line switched by the first changeover switch 33 and the third changeover switch 46 is any one of the clock line, chip selector line, output line, and input line.

[0041] Next, the operation of the communication system 1 having the above configuration will be described with reference to Figure 3 First, when the ignition switch of the vehicle is turned on and power is supplied from the central ECU 2 to the first power supply lines L11 and L12, power is supplied to the input / output control unit 32, and the input / output control unit 32 is activated.

[0042] When the input / output control unit 32 is activated, the input / output control unit 32 turns on the power switch 34 (S1). When the power switch 34 is turned on, power is supplied to the second power supply line L21 connected to the first power supply line L11 through the first and second connectors 31 and 42. When power is supplied to the second power supply line L21, power is supplied to the timer circuit 47 of the input / output interface unit 4, and the timer circuit 47 is activated.

[0043] Next, the input / output control unit 32 switches the first switch 33 to the first terminal T1 (S2) and starts measuring for a certain period of time (S3). After that, the input / output control unit 32 waits for the input of the code pulse to the first terminal T1 (S4).

[0044] Meanwhile, when the timer circuit 47 is activated, the timer circuit 47 starts measuring for a certain period of time (S11). Next, the timer circuit 47 switches the second and third switches 45, 46 to the pulse output unit 44 (S12). As a result, power is supplied to the pulse output unit 44, and the pulse output unit 44 is activated. When the pulse output unit 44 is activated, the pulse output unit 44 reads the code from the code setting unit 43 (S13) and outputs a code pulse indicating the read code to the second communication line L23 (S14).

[0045] The code pulse output to the second communication line L23 is input to the first terminal T1 of the input / output control unit 32 via the first communication line L13. When the code pulse is received from the first terminal T1 (Yes in S4), the input / output control unit 32 determines whether the code represented by the code pulse matches the regular code pre-stored in the memory (S6). When the code matches the regular code (Yes in S6), the input / output control unit 32 switches the first switch 33 to the second terminal T2 (S7), and then executes the normal process for controlling the input / output drive unit 41 of the input / output interface unit 4.

[0046] Meanwhile, when the timer circuit 47 of the input / output interface unit 4 finishes measuring for a certain period of time (Yes in S15), the timer circuit 47 switches the second and third switches 45, 46 to the input / output drive unit 41 (S16), and then executes the normal process in which the input / output drive unit 41 operates under the control of the input / output control unit 32 of the area ECU3.

[0047] On the contrary, when the code represented by the code pulse does not match the regular code (No in S6), or when the code pulse is not input to the first terminal T1 even after a certain period of time or longer (Yes in S5), the input / output control unit 32 determines that the regular input / output interface unit 4 is not connected, turns off the power switch 34 (S8), and then proceeds to S7. When the power switch 34 is turned off, no power is supplied to the unauthorized device connected to the first connector 31, and access by the unauthorized device can be prevented.

[0048] A reprogramming device (external device, not shown) capable of obtaining programs and data stored in the memories of the central ECU 2 and the regional ECU 3 is detachably connected to the above communication system 1. Through communication with the reprogramming device, the central ECU 2 adds its programs and data to the reprogramming device and commands the regional ECU 3 to add its programs and data to the reprogramming device. Before connecting the input / output interface unit 4, the regular code stored in the above regional ECU 3 can be added (obtained) through communication with the reprogramming device (external device).

[0049] In the above example, the regional ECU 3 communicates with the reprogramming device via the central ECU 2, and the regional ECU 3 and the reprogramming device can communicate directly with each other. The reprogramming device can be connected to the communication system 1 in a wired or wireless manner.

[0050] According to the above embodiment, when starting the power supply, the input / output control unit 32 switches the first switch 33 to the first terminal T1 for a certain period of time, determines whether the code represented by the code pulse received from the first terminal T1 is a regular code, and when the code is not a regular code, turns off the power switch 34 to cut off the power supplied from the first power line L11 to the second power line L21. Therefore, unauthorized access can be prevented when an unauthorized device is connected to the first connector 31 of the regional ECU 3.

[0051] According to the above embodiment, the input / output control unit 32 can obtain the regular code through communication with the reprogramming device.

[0052] According to the above embodiment, in the input / output interface unit 4, when starting the power supply, the timer circuit 47 switches the second switch 45 and the third switch 46 to the pulse output unit 44 for a certain period of time, and causes the pulse output unit 44 to output a code pulse to the second communication line L23. Therefore, even when the input / output drive unit 41 is not provided with a microcomputer or the like and cannot perform complex communication, the input / output drive unit 41 can transmit a code pulse with a simple structure when starting the power supply.

[0053] The present invention is not limited to the above embodiments, and modifications, improvements, etc. can be made appropriately. In addition, as long as the object of the present invention can be achieved, the materials, shapes, sizes, quantities, arrangement positions, etc. of the components in the above embodiments are optional and not limited.

[0054] For example, the input / output drive unit may also be provided on the substrate of the zone ECU 3. The input / output drive unit provided in the zone ECU 3 is connected to a standard electrical device that is commonly installed in both high-class vehicles and low-class vehicles, and the input / output drive unit 41 provided in the input / output interface unit 4 may also be connected to an extended electrical device installed in high-class vehicles. In this case, the input / output interface unit 4 is only installed in the communication system 1 of high-class vehicles and not in the communication system 1 of low-class vehicles.

[0055] According to the above-described embodiment, the input / output control unit 32 obtains a regular code through communication with the reprogramming device, but the present invention is not limited thereto. For example, an operation switch may also be provided in the zone ECU 3, and the input / output control unit 32 may also obtain a regular code based on the ON-OFF information of the operation switch.

[0056] According to the above-described embodiment, the first and second connectors 31 and 42 are used as the first and second connection units, but the present invention is not limited thereto. As the first and second connection units, those configurations capable of being connected to pin headers may be adopted.

[0057] Here, the features of the embodiments of the control device and the input / output interface unit according to the present invention described above will be briefly summarized and listed below in [1] to [3].

[0058] [1]. A control device (3) that controls an input / output interface unit (4), the input / output interface unit (4) including an input / output circuit (41) that is one of an input circuit and an output circuit for an electrical device (5), the control device (3) including:

[0059] First power supply lines (L11, L12) to which power is supplied;

[0060] A first communication line (L13) through which signals are transmitted;

[0061] A first connection unit (31) configured to connect a second power supply line (L21, L22) and a second communication line (L23) of the input / output interface unit (4) to the first power supply lines (L11, L12) and the first communication line (L13);

[0062] A control unit (32) that controls the input / output interface unit (4); and

[0063] A first switching unit (33) that switches the connection destination of the first communication line (L13) between a first terminal (T1) that receives a code pulse and a second terminal (T2) that receives or outputs a communication signal.

[0064] When starting the supply of the power, the control unit (32) switches the first switching unit (33) to the first terminal (T1) for a certain period of time, determines whether the code indicated by the code pulse received from the first terminal (T1) is a regular code, and cuts off the power supplied from the first power supply lines (L11, L12) to the second power supply lines (L21, L22) when the code is not the regular code.

[0065] [2]. The control device (3) according to [1], wherein the control unit (32) obtains the regular code through communication with an external device.

[0066] [3]. An input / output interface unit (4) includes an input / output circuit (41) which is one of an input circuit and an output circuit for an electrical device (5), and operates according to communication with a control device (3). The input / output interface unit (4) includes:

[0067] Second power supply lines (L21, L22) to which power is supplied;

[0068] A second communication line (L23) through which signals are transmitted;

[0069] A second connection unit (42) which connects the first power supply lines (L11, L12) and the first communication line (L13) of the control device (3) to the second power supply lines (L21, L22) and the second communication line (L23);

[0070] A pulse output unit (44) which outputs code pulses;

[0071] A second switching unit (45) which switches the connection destination of the second power supply lines (L21, L22) between the pulse output unit (44) and the input / output circuit (41);

[0072] A third switching unit (46) which switches the connection destination of the second communication line (L23) between the pulse output unit (44) and the input / output circuit (41); and

[0073] A timer circuit (47) which switches the second switching unit (45) and the third switching unit (46) to the pulse output unit (44) for a certain period of time when starting the supply of the power, and causes the pulse output unit (44) to output the code pulses to the second communication line (L23).

[0074] According to the control device having the configuration [1], the control unit can determine whether the code pulse transmitted from the device connected to the first connection unit at the time of starting the power supply is a regular code pulse, and can cut off the power supplied to the device connected via the first connection unit when the code pulse is not a regular code pulse. Therefore, unauthorized access can be prevented when an unauthorized device is connected to the first connection unit of the control device.

[0075] According to the control device having the configuration [2], a regular code pulse can be obtained through communication with an external device.

[0076] According to the input / output interface unit having the configuration [3], the timer circuit switches the second switching unit and the third switching unit to the pulse output unit for a certain period of time at the time of starting the power supply, and causes the pulse output unit to output a code pulse to the second communication line. Therefore, even if a microcomputer or the like is not provided and complex communication cannot be performed, a code pulse can be transmitted with a simple configuration at the time of starting the power supply.

[0077] According to the present invention, a control device and an input / output interface unit can be provided that can prevent unauthorized access to the control device when an unauthorized device is connected to the control device.

Claims

1. A control device configured to control an input / output interface unit, the input / output interface unit including an input / output circuit that is one of an input circuit and an output circuit for an electrical device, the control device including: A first power supply line to which power is supplied; A first communication line through which signals are transmitted; A first connection unit configured to connect a second power supply line and a second communication line of the input / output interface unit to the first power supply line and the first communication line; A control unit configured to control the input / output interface unit; And A first switching unit configured to switch a connection destination of the first communication line between a first terminal that receives a code pulse and a second terminal that receives or outputs a communication signal, Wherein, when starting the supply of power, the control unit switches the first switching unit to the first terminal for a certain period of time, determines whether the code indicated by the code pulse received from the first terminal is a regular code, and when the code is not the regular code, the control unit cuts off the power supplied from the first power supply line to the second power supply line; When the code is the regular code, the control unit switches the first switching unit to the second terminal, and the input / output interface unit performs corresponding processing; and when the code pulse is not input to the first terminal after the certain period of time, the control unit determines that the input / output interface unit is not communicatively connected to the control unit and cuts off the power supplied from the first power supply line to the second power supply line.

2. The control device according to claim 1, Among them, The control unit obtains the regular code through communication with an external device.

3. An input / output interface unit including an input / output circuit that is one of an input circuit and an output circuit for an electrical device and configured to operate based on communication with a control device, the input / output interface unit including: A second power supply line to which power is supplied; A second communication line through which signals are transmitted; A second connection unit configured to connect a first power supply line and a first communication line of the control device to the second power supply line and the second communication line; A pulse output unit configured to output a code pulse; A second switching unit configured to switch a connection destination of the second power supply line between the pulse output unit and the input / output circuit; A third switching unit configured to switch a connection destination of the second communication line between the pulse output unit and the input / output circuit; And A timer circuit configured to switch the second switching unit and the third switching unit to the pulse output unit for a certain period of time when starting the supply of power and cause the pulse output unit to output the code pulse to the second communication line; The control device is configured to receive the code pulse and determine whether the code indicated by the code pulse is a regular code, When the code is not the regular code, the control device cuts off the power supplied from the first power supply line to the second power supply line; When the code is the regular code, the input / output interface unit performs corresponding processing; When the code pulse has not been input to the control device after the certain period of time, the control device determines that the input / output interface unit is not communicatively connected to the control device and cuts off the power supplied from the first power supply line to the second power supply line.

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