JPH1168594A - On-vehicle electronic controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent radiation noise, caused by a reference clock of an electronic controller, from mixing with an FM radio receiver that is mounted on a vehicle by providing a receiving means which receives external specific information and a frequency-changing means which changes the frequency of a variable reference clock generating means, based on the signal from the receiving means. SOLUTION: A receiving means 6 of an electronic controller 1 of a vehicle receives external specific information JG. A frequency-changing means 7 changes the frequency of a variable reference clock generating means 3 based on a signal from the means 6. The frequency of a reference clock is changed based on the information JG that is received this way, and a generated higher harmonics component is set so that it is separated from the channel frequency of an FM radio broadcasting station. Then, radiation noise due to the higher harmonics component of the reference clock is prevented from coinciding with a selected channel frequency of an FM radio receiver, or becoming close to it to mix with it and being head from FM radio.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle electronic control device for controlling the behavior of a vehicle, and more particularly, to preventing a harmonic component of a reference clock from being mixed as noise into an FM radio receiver mounted on the vehicle. The present invention relates to an electronic control device of a vehicle to be driven.

[0002]

2. Description of the Related Art In a conventional electronic control unit for a vehicle, an MPU (micro control unit) is required to appropriately control various functions of the vehicle such as an electronic control unit (EPS) of an electric power steering device and an ABS (Anti Brake System). A device configured to execute various calculations, processes, and the like using a processing unit is known.

An MPU (micro processing unit) is configured to operate based on a high-frequency reference clock generated from a high-precision crystal oscillator.

The frequency of the reference clock is generally 10M in consideration of the processing speed of the electronic control unit in which the MPU is mounted.
Hz to 30 MHz are used. Note that the reference clock is formed with a pulse waveform.

[0005]

A conventional electronic control unit for a vehicle has a driving frequency of 10 MHz to 30 MHz to drive an MPU.
Since a reference clock of Hz is used and the reference clock is generated in a pulse waveform (rectangular wave), a harmonic component that is an integral multiple of the reference clock frequency is generated as radiation noise.

[0006] On the other hand, as a channel frequency of an FM radio broadcasting station, for example, a frequency band of 70 MHz to 100 MHz is allocated in Japan.

For example, FM broadcast stations that can be received in the Tokyo area include TOKYO-FM (80.0 MHz), J-WAV
E (81.3 MHz), NHK-FM (82.5 MH)
z), FM Yokohama (80.4 MHz, 84.7 MH)
z), bay-FM (77.7 MHz, 78 MHz, 7
9.3 MHz).

Assuming that the frequency of the reference clock used for the electronic control unit of the vehicle is set to 16 MHz, the reception (70 MHz to 70 MHz) of the FM radio receiver mounted on the vehicle is assumed.
100 MHz), the harmonic component of the reference clock, which is considered to have an effect on the
It is 96 MHz of the fifth harmonic, especially the fifth harmonic (80
MHz) coincides with TOKYO-FM (80.0 MHz), and has a problem of being mixed into the FM radio receiver as radiation noise.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and an object of the present invention is to prevent an FM radio receiver mounted in a vehicle from being mixed with radiation noise caused by a reference clock of an electronic control unit. To provide an electronic control device for a vehicle.

[0010]

In order to solve the above-mentioned problems, an electronic control unit for a vehicle according to the present invention comprises a variable reference clock generating means capable of generating a plurality of reference clocks, and a receiving means for receiving external identification information. Frequency changing means for changing the frequency of the variable reference clock generating means based on a signal from the receiving means.

An electronic control unit for a vehicle according to the present invention includes a variable reference clock generating means capable of generating a plurality of reference clocks, a receiving means for receiving external identification information, and a variable reference clock based on a signal from the receiving means. Frequency changing means for changing the frequency of the clock generating means, so that the frequency of the reference clock is changed based on the received external specific information so that the generated harmonic components are separated from the channel frequency of the FM radio broadcasting station. Can be set.

Further, the receiving means according to the present invention is characterized in that the receiving means includes a code detecting means for detecting a code of the external specifying information.

[0013] Since the receiving means according to the present invention includes the code detecting means for detecting the code of the external specifying information, the external specifying information (diagnosis signal) supplied from the failure diagnosis device of the vehicle.
Can detect a specific code corresponding to the channel frequency of the FM radio broadcast.

Further, the receiving means according to the present invention is characterized in that it comprises frequency detecting means for detecting the frequency of the external identification information.

Since the receiving means according to the present invention includes the frequency detecting means for detecting the frequency of the external specifying information, it is possible to detect the FM channel frequency of the car radio as the external specifying information.

Further, the frequency changing means according to the present invention is characterized in that it comprises voltage value setting means for setting the frequency of the reference clock.

Since the frequency changing means according to the present invention includes the voltage value setting means for setting the frequency of the reference clock, it is possible to change the frequency setting signal based on the received external specifying information to change the reference clock frequency. Can be.

Further, the external identification information according to the present invention is characterized in that it is a diagnostic signal supplied from an external diagnostic device.

Since the external specifying information according to the present invention is a diagnostic signal supplied from an external diagnostic device, it is possible to change the frequency of the reference clock using an interface between the external diagnostic device and an electronic control unit (ECU). it can.

Further, the external identification information according to the present invention includes:
It is a channel signal received by an FM radio receiver.

Since the external specifying information according to the present invention is a channel signal received by the FM radio receiver, the frequency of the reference clock can be automatically changed inside the electronic control unit of the vehicle.

[0022]

Embodiments of the present invention will be described below with reference to the accompanying drawings. Note that the present invention changes the reference clock of the electronic control device based on external information, and prevents harmonic components of the reference clock from being mixed as radiated noise into the FM radio receiver mounted on the vehicle. .

FIG. 1 is a block diagram of a main part of an electronic control unit for a vehicle according to the present invention. 1, an electronic control unit 1 for a vehicle includes an oscillating unit 2, a variable reference clock generating unit 3, an MPU (micro processing unit) 4, a control unit 5, a receiving unit 6, and a frequency changing unit 7.

The oscillating means 2 is composed of, for example, a PLL circuit, and has a fundamental frequency (5 MHz to 8 MHz) of the crystal unit X.
And oscillates the oscillation signal X _O to generate a variable reference clock
To supply.

The crystal oscillator X has a high frequency accuracy and is stable against environmental conditions such as temperature. The oscillation frequency is adjusted according to the configuration of the oscillation circuit 2.

The variable reference clock generating means 3 includes, for example, P
Oscillator 2 composed of LL (Phase Locked Loop) circuit
10MHz~30MHz an oscillation signal X _O supplied from
To generate a reference clock C _L
In the reference clock C _L drives the MPU (micro processing unit) 4. Note that the reference clock C
_L is described as 16 MHz.

Further, the variable reference clock generating means 3, for example, a voltage - with a frequency varying means having a frequency conversion function, change the frequency of the reference clock C _L based on the voltage value N _D to be supplied from the frequency changing means 7 Then, the MPU (micro processing unit) 4 is driven by the new reference clock C _LO .

The MPU (micro processing unit) 4 has various arithmetic functions, processing functions, memories, etc., and is driven by the reference clock C _L or the reference clock C _LO supplied from the variable reference clock generating means 3. to the control means 5 which are provided corresponding to various data D _I to the EPS and ABS, or the like.

Here, the change range of the reference clock C _L and F
Next, the reception of the M radio will be described. Set the reference clock C _L to 1
If set to 6 KHz, when significantly changing the frequency of the reference clock C _L, MPU (micro processing unit) had a significant change in the fourth operation, for example, processing speed, etc. is changed by the electronic control apparatus for a vehicle A phenomenon occurs in which the operation 1 is not performed normally.

Therefore, 0.01% (16K) of the reference clock C _L (= 16 MHz) is set as a range that does not affect the operation of the MPU (micro processing unit) 4.
The Hz) which is lower by frequency 15.984MHz and new reference clock C _LO.

On the other hand, the channel frequency interval Δf assigned to FM radio broadcasting stations in Japan is 0.1 MHz.
(100 KHz), it has been confirmed that a signal having a frequency separated by 0.05 MHz (50 KHz) from the channel frequency f _C of the FM radio broadcasting station is not received by the FM radio receiver (FM radio).

Accordingly, the reference clock C _LO (= 15.98)
The 4th harmonic component of 79.92 MHz and the 6th harmonic component of 95.904 MHz become radiated noise and are mixed into an FM radio receiver (FM car radio) mounted on a vehicle.

The fifth harmonic component of 79.92 MHz is the channel frequency 8 of the FM radio broadcasting station actually used.
0 MHz (TOKYO-FM) to 0.08 MHz (8
0 KHz) apart and will not be received by the FM radio receiver.

The sixth harmonic component 95.904 MHz
Is apart from the channel frequency 96 MHz assigned to the FM radio broadcasting station by 0.096 MHz (96 KHz), and is not received by the FM radio receiver even if the FM radio broadcasting station having the channel frequency of 96 MHz is opened.

From the above, the channel frequency of 80 MH
Only when the FM radio station of z and 96 MHz is received by the FM radio receiver (FM car radio), the setting is changed to the reference clock C _LO (= 15.984 MHz), and the reception of the other FM radio stations is changed. Is the reference clock C
It may be set as _L (= 16 MHz).

The receiving means 6 includes code (code) detecting means,
Alternatively, a frequency detecting means is provided, and based on a diagnostic signal of a code (code) supplied from an external failure diagnostic device 8 or external identification information J _G including a channel frequency of an FM radio broadcast station received by an FM car radio, The frequency data of the external identification information _JG is detected, and the frequency data _SD is provided to the frequency changing means 7.

The external failure diagnosis device 8 is a device installed at a vehicle maintenance shop, a service station, or the like, for inspecting the failure of the vehicle or checking various function settings.

The external identification information J _G is stored in the external failure diagnostic device 8.
Since the diagnostic signal is supplied from the (external diagnostic device), the frequency of the reference clock can be changed from the external failure diagnostic device 8 via the interface of the electronic control unit 1 of the vehicle.

Further, the external identification information J according to the present invention
_G is because the channel signals received FM radio receiver (FM car radio 9), it is possible to automatically change the frequency of the reference clock C _L by the electronic control apparatus inside 1 of the vehicle.

FIG. 2 is a block diagram of a main part of an embodiment of the receiving means according to the present invention. In FIG. 2, the receiving means 6 includes a timing pulse generating means 15, a code storing means 11, a data access means 12, and a code converting means 1.
And a code detecting means 10 provided with the code number 3.

The timing pulse generating means 15 includes an MPU
4 a reference clock C _L for driving by dividing a constituted by a signal generator for generating timing pulses of a predetermined frequency, and supplies the timing pulse T _P in the code storage means 11.

The code storage means 11 has a rewritable memory such as a RAM, and stores a code (code) corresponding to the channel frequency of the FM radio included in the external identification information _JG supplied from the external failure diagnostic device 8. Timing pulse T
_P holds and stores a period that is supplied to the data access means 12 holds the code (the code) as code data D _C.

Further, the code storage means 11 stores another external specifying information J _G during the period in which the timing pulse _TP is supplied.
Is supplied, the code (code) included in the external identification information _JG is stored and held as a new code (code).

The code (code) included in the external identification information _JG is formed of, for example, a binary code corresponding to the radio channel frequency.

The data access unit 12 has a data access functions, sends code data D _C supplied from the code storage means 11 to the code conversion unit 13, the frequency data corresponding to the code data D _C from the code conversion means 13 _SD is read and supplied to the frequency changing means 7.

The code conversion means 13 is composed of a memory such as a ROM, and stores frequency data _SD corresponding to the code data D _C in advance, and when the code data D _C is supplied from the data access means 12, supplies frequency data S _D corresponding to the code data D _C to the data access means 12.

[0047] The frequency data S _D, from the channel frequency of the FM radio corresponding to the code data D _C, N th harmonic of the reference clock C _L (e.g., the fifth harmonic) and N + 1-order harmonics (e.g. , The sixth harmonic) are set to a value of the new reference clock _CLO such that the frequency is sufficiently far away and the FM radio receiver (FM car radio) does not receive the frequency.

As described above, the receiving means 6 according to the present invention
Is provided with a code detecting means 10 for detecting a code of the external identification information J _G , so that based on the external identification information J _G (diagnosis signal) supplied from the vehicle failure diagnostic device 8, the channel frequency of the FM radio broadcast is changed to The corresponding specific code can be detected.

FIG. 3 is a block diagram of a main part of another embodiment of the receiving means according to the present invention. In FIG. 3, the receiving means 20 includes a frequency determining means 22, a frequency storing means 23,
It has a frequency detecting means 21 provided with a frequency converting means 24.

The frequency discriminating means 22 comprises, for example, band-pass filters, detectors and the like for a plurality of frequency bands.
When the external specific information _JG that matches the channel frequency of the FM radio is supplied from the M car radio 9, the channel frequency f _C is detected and the frequency discrimination signal D _F of, for example, a binary code is detected.
Is provided to the frequency storage means 23.

The frequency storage means 23 stores a rewritable R
A frequency discriminating signal _DF corresponding to the channel frequency f _C is stored and stored, and is provided to the frequency converting means 24 as frequency data F _O.

The frequency conversion means 24 is constituted by a memory such as a ROM, and stores frequency data _SD corresponding to the frequency data F _O of the channel frequency f _C of the FM radio in advance. When F _O is supplied, supplies the frequency data S _D corresponding to the frequency data F _O frequency changing means 7.

[0053] The frequency data S _D is, N harmonics code data D reference _C from the channel frequency of the FM radio corresponding to the clock C _L (e.g., the fifth harmonic) and N + 1-order harmonics (e.g., The new reference clock _CLO is set to a value such that the frequency of the sixth harmonic is sufficiently far away so as not to be received by the FM radio receiver (FM car radio).

As described above, the receiving means 20 according to the present invention
Has the frequency detecting means 21 for detecting the frequency of the external identification information J _G , so that the FM channel frequency of the car radio 9 can be detected as the external identification information J _G.

The frequency changing means 7 includes a voltage value setting means which is constituted by a memory such as a ROM and stores frequency-voltage value conversion data in advance, for example. The code detecting means 10 shown in FIG. When the frequency data S _D is supplied from the detection means 21, the corresponding voltage value N _D
Reading, variable reference clock generating means 3 a voltage value N _D
To supply.

[0056] frequency changing means 7 according to the present invention, reference clock C because with a voltage value setting means for setting the frequency of the _L, the voltage value N _D based on the external specification information J _G received
Can be changed to change the reference clock frequency.

[0057] Voltage value N _D is variable reference clock generating means 3
, The voltage of the variable reference clock generating means 3
The frequency variable means having a frequency conversion function changes the reference clock C _L (16 MHz) to a new reference clock C _LO (for example, 15.984 MHz), and changes the reference clock C _LO.
Drives an MPU (micro processing unit) 4.

By changing the reference clock C _L (16 MHz) to a new reference clock (15.984 MHz), for example, the channel frequency f _C of the FM radio station on the FM car radio 9 is changed to 80 MHz (TOKYO-FM) or 96 MHz. Is selected, the reference clock C _L (16
It is possible to prevent radiation noise generated by harmonic components (fifth and sixth harmonics) from entering the FM car radio 9.

In the FM car radio 9, the channel frequency f _C of the FM radio station is 80 MHz (TOKYO-FM).
Or a frequency other than 96 MHz, the reference clock C
Remains of _L (16MHz), the reference clock C _L (16MH
Radiation noise generated by the harmonic component of z) can be prevented from entering the FM car radio 9.

[0060] Incidentally, a reference clock C _L in the present embodiment 1
Although the case of setting to 6 MHz is shown, the reference clock C _L
Even when set to another frequency, the change of the reference clock C _L can be applied to the present invention that the small range that does not affect the operation of the MPU.

[0061]

As described above, the control means of the electronic control unit for a vehicle according to the present invention comprises: a variable reference clock generating means capable of generating a plurality of reference clocks; a receiving means for receiving external identification information; Frequency changing means for changing the frequency of the variable reference clock generating means based on the signal from the receiving means, wherein the frequency of the reference clock is changed based on the received external identification information, and the generated harmonic component is FM radio. Since it can be set so as to be away from the channel frequency of the broadcasting station, the radiated noise due to the harmonic component of the reference clock coincides with or becomes close to the channel frequency selected by the FM radio receiver. It can prevent hearing.

Further, the receiving means according to the present invention includes a code detecting means for detecting a code of the external specifying information, and the external specifying information (diagnosis signal) supplied from the vehicle failure diagnostic device.
Can detect the specific code corresponding to the channel frequency of the FM radio broadcast, so that the reference clock can be easily changed so as not to be mixed as noise into the FM radio channel frequently used in a repair shop or service station. .

Further, the receiving means according to the present invention includes frequency detecting means for detecting the frequency of the external specifying information, and can detect the FM channel frequency of the car radio as the external specifying information. Even when the FM channel is selected, a reference clock that does not mix into the FM radio channel as radiation noise can be automatically set.

Further, the frequency changing means according to the present invention comprises:
A voltage value setting means for setting the frequency of the reference clock is provided, and the frequency setting signal can be changed based on the received external identification information to change the reference clock frequency. It can be prevented from being heard as noise from the radio at or near the channel frequency.

Further, the external identification information according to the present invention includes:
Since the diagnostic signal is supplied from the external diagnostic device, the frequency of the reference clock can be changed using the interface of the external diagnostic device and the electronic control unit of the vehicle. It is possible to realize FM radio noise prevention without any change.

The external specifying information according to the present invention is a channel signal received by the FM radio receiver. Since the frequency of the reference clock can be automatically changed inside the electronic control unit of the vehicle, the area is limited. Noise prevention of FM radio can be realized without the need.

Thus, it is possible to provide an electronic control unit for a vehicle which has a simple configuration and can prevent noise on an FM car radio caused by a harmonic component of a reference clock, which can be easily adjusted.

[Brief description of the drawings]

FIG. 1 is a block diagram of a main part of an electronic control unit for a vehicle according to the present invention.

FIG. 2 is a block diagram of a main part of an embodiment of a receiving means according to the present invention;

FIG. 3 is a block diagram showing a main part of another embodiment of the receiving means according to the present invention;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Electronic control device of a vehicle, 2 ... Oscillating means, 3 ... Variable reference clock generating means, 4 ... MPU (micro processing unit), 5 ... Control means, 6, 20 ... Receiving means, 7 ... Frequency converting means, 8: Fault diagnosis machine, 9: FM car radio, 10: Code detection means, 11: Code storage means, 12: Data access means, 13: Code conversion means, 15: Timing pulse generation means, 21: Frequency detection means, 22 ... frequency discriminating means, 23 ... frequency storing means, 24 ... frequency converting means, X ... crystal oscillator, _CL , C
_LO ... reference clock, D _C ... code data, D _F ... frequency discrimination signal, D _I ... data, F _O ... frequency data, J _G ... external specific information, N _D ... voltage value, S _D ... frequency data, X _O ... oscillation signal.

Claims (6)

[Claims] 1. An electronic control unit for a vehicle equipped with an FM (Frequency Modulation) radio receiver, comprising: a variable reference clock generating means capable of generating a plurality of reference clocks; a receiving means receiving external identification information; Frequency changing means for changing the frequency of the variable reference clock generating means based on a signal from the means. 2. The electronic control device for a vehicle according to claim 1, wherein said receiving means includes a code detecting means for detecting a code of the external specific information. 3. The electronic control device for a vehicle according to claim 1, wherein said receiving means includes frequency detecting means for detecting a frequency of the external identification information. 4. The electronic control device for a vehicle according to claim 1, wherein said frequency changing means includes a voltage value setting means for setting a frequency of a reference clock. 5. The electronic control device for a vehicle according to claim 1, wherein the external identification information is a diagnostic signal supplied from an external diagnostic device. 6. The vehicle electronic control device according to claim 1, wherein the external identification information is a channel signal received by an FM radio receiver.