JPH06209349A - Mutual communication equipment for controller - Google Patents

Abstract

PURPOSE:To perform mutual communication at a lower cost. CONSTITUTION:In a first controller 11 on the transmission side, a map to convert the control data (for example, fundamental fuel quantity) to an output time is stored in a ROM 21, and a CPU 23 retrieves an output time TD. A counting start signal consisting of two pulse signals P1 and P2 is outputted, and a counting end signal consisting of two pulses P3 and P4 is outputted when the output time TD elapses after the output of the second pulse signal of the counting start signal. In a second controller 12 on the reception side, the output time TD is counted by a timer 22 to retrieve the control data.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intercommunication device for communicating control data among a plurality of control devices (for example, CPUs).

[0002]

2. Description of the Related Art For example, in an automobile, in order to perform fuel injection control of an engine, ignition timing control or shift control of an automatic transmission, a CPU (control device) for each control is provided and the functions are shared. The control of each CPU is simplified, the efficiency is improved, and the execution time is shortened by the parallel operation. Here, the control data are mutually communicated between the CPUs so that the control data can be used by the CPUs.

The following is a conventional example of this type of mutual communication device. That is, FIG. 7 shows a first conventional example, in which, for example, a first control device 1 for performing fuel injection control of an engine and a second control device 2 for performing shift control of an automatic transmission are provided. There is. When a clock signal is input from the first control device 1 to the second control device 2, the control data is transferred between the first control device 1 and the second control device 2 in synchronization with this signal. A so-called serial communication method is adopted in which communication is performed via A and B.

As a second conventional example, a plurality of communication lines C _{1 to} C ₆ are provided as shown in FIG.
There is a parallel interface system in which digital signals are communicated between the second control device 4 and the second control device 4 via communication lines C _{1 to} C ₆ . As a third conventional example, as shown in FIG. 9, integrated circuits 7 and 8 dedicated to communication are provided in the first and second control devices 5 and 6, and the first control device 5 is provided via the integrated circuits 7 and 8. And the second control device 6 are made to communicate with each other.

[0005]

However, such a conventional intercommunication device has the following problems. That is, in the first conventional example, since mutual communication is performed in time synchronization, there is a problem that communication of control data may not be in time depending on the performance of the control device. Also,
There is a problem that a line for transmitting the clock signal is required and the cost becomes high.

Further, in the second conventional example, since communication is performed by a digital signal, there is a problem that the number of communication lines is large and the cost is high for the amount of communication. Further, in the third conventional example, since the integrated circuits 7 and 8 dedicated to communication are provided, there is a problem that the cost becomes high. The present invention has been made in view of such circumstances, and an object of the present invention is to provide an intercommunication device of a control device capable of performing intercommunication while reducing costs.

[0007]

Therefore, according to the present invention, as shown in FIG. 1, in an intercommunication device of a control device in which a plurality of control devices are made to mutually communicate control data, each control device is controlled. To the control data transmission section of the control data transmission section, and a conversion means for converting the control data into an output time, and a timing start signal composed of two pulse signals having a predetermined time interval, and a second timing start signal. Output means for outputting a timing end signal composed of two pulse signals having a predetermined time interval after the output time has elapsed from the time when the pulse signal was output, and the control data receiving section of each control device is provided with the timing time. Timing means for starting timing when the second pulse signal of the starting signal is input and ending timing when the first pulse signal of the timing ending signal is input; Based Reading means for reading the control data,
I was prepared.

[0008]

According to the above configuration, each control device has an input time from the input of the second pulse signal of the timing start signal to the input of the first pulse signal of the timing end signal. The control data of the other control device is read from. Incidentally, if the time intervals of the two pulse signals of the timing start signal and the timing end signal respectively are set in advance based on the device that transmits, it becomes possible to determine the control device that is the transmission source.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. In FIG. 2 showing the present embodiment, first and second control devices 11 and 12 composed of a microcomputer are provided, and these first and second control devices 11 and 12 are connected by two communication lines D ₁ and D ₂ . It is connected. The first control device
Numeral 11 controls the fuel injection of the engine.
Further, the second control device 12 is adapted to perform shift control of the automatic transmission of the vehicle.

As shown in FIG. 3, the first and second control devices 11 and 12 are provided with a ROM 21, a timer 22, and a CPU 23. The ROM 21 stores a map of control data (for example, basic fuel amount) and output time. The timer 22 is for measuring the output time, and C
The PU 23 is provided with software including a conversion unit, an output unit, and a reading unit.

Next, the operation will be described with reference to the flowcharts of FIGS. 4 and 5 and the timing chart of FIG.
Note that, here, a case where control data is transmitted from the first control device 11 to the second control device 12 will be described as an example. First, the operation of the first control device 11 on the transmission side will be described based on the flowchart of FIG.

In the first controller 11 on the transmission side, the CPU 23
Retrieves the output time from the map of the control data and the output time stored in the ROM 21 (step 1), and outputs a timing start signal composed of _two pulse signals P ₁ and P ₂ having a predetermined time interval. (Step 2), the timer 22 measures time, and two pulse signals P having a predetermined time interval after the output time elapses from the time when the _second pulse signal P ₂ of the timing start signal is output (Step 3). _A signal for ending timekeeping consisting of ₃ and P ₄ is output (step 4).

A signal as shown in FIG. 6 is transmitted from the first controller 11 to the second controller 12 via the communication line D ₁ . The step 1 corresponds to the conversion means, and the steps 2 to 5 correspond to the output means. Next, the operation of the second control device 12 on the receiving side will be described based on the flowchart of FIG.

When the pulse signal P ₁ is input from the first controller 11 to the second controller 12 via the communication line D ₁ (step 11), the timer 22 of the second controller 12 starts counting ( When the pulse signal P ₂ is further input in step 12), the timer 22 finishes measuring time (steps 13 → 14). When the input period T _{S of the} pulse signals P ₁ and P ₂ is a predetermined value,
It is determined that the signal for starting timekeeping has been input (step 15),
The timer 22 starts measuring time (step 16).

When the pulse signal P ₃ is input, the timer 22 finishes the time counting (steps 17 → 18) and further starts the time counting (step 19) when the pulse signal P ₄ is input. The time measurement is finished (step 20 → 21). Then, when the input period T _{E of} the pulse signals P ₃ and P ₄ is a predetermined value, it is determined that the timing end signal is input (step 22). The timing start signal is formed by _two pulse signals P ₁ and P ₂ , and the timing end signal is generated by two pulse signals P ₃
And P ₄ and the input periods of the pulse signals P ₁ and P _{2 and} the input periods of the pulse signals P ₃ and P ₄ are set in advance, even if a noise signal from the engine is input, this noise The signal does not erroneously recognize the timing start signal and the timing end signal, and is less susceptible to the noise signal. Then, based on the input time T _D of the pulse signal P ₂ and the pulse signal P ₃ , for example, the CPU 23 determines that the ROM 21
Is searched for control data (step 23), and it is determined that the searched control data has been communicated from the first control device 11.

The communication is performed by the second control device 12 through the first control.
Communication line D for control device 11₂Done through.
In addition, steps 12 to 21 are the time measuring means, and steps 22 and 23 are the reading means.
Corresponds to taking means. As explained above, two pulses
Signal P₁, P₂The second pulse of the signal for starting the clock consisting of
Signal P₂Is the first signal for timing end after is output
Pulse signal P₃Measure the time until
Read the control data of the other controller 11, 12 from the measurement time
So that two communication lines D₁, D₂By
Mutual communication can be performed and cost reduction can be achieved. Special
In addition, recent microcomputers have a large timekeeping function.
The communication method is optimal because of its wide range. Well
The signal for starting time measurement is set to a predetermined time interval T_STwo pas with
Loose signal P₁And P₂Formed by the
Predetermined time interval T_ETwo pulse signals P with ₃And P_Four
Since it is formed by the
Depending on the time interval T_S, Of the signal for ending timing
Time interval T_EIf you set the
It became possible to identify the control device, and
Communication between the devices is possible. Also, depending on the noise signal
The timing start signal and the timing end signal
Is not easily affected by noise signals, and
It is the most suitable for the storage.

[0017]

As described above, according to the present invention, after the second pulse signal of the timing start signal of the other control device is output, the first pulse signal of the timing end signal is input. Since the output time until the start of measurement is measured and the control data of the other control device is read from this measured time, the communication line can be suppressed to the minimum and the cost can be reduced. Further, since the time measurement start signal and the time measurement end signal are formed by two pulse signals each having a predetermined time interval, if the time interval is set according to the control device of the transmission source, the transmission source can be transmitted with the minimum communication line. The control device can be recognized, communication between a large number of control devices can be performed, and it is less susceptible to noise signals.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of the present invention.

FIG. 2 is a configuration diagram showing an embodiment of the present invention.

FIG. 3 is a block diagram of the mutual communication device of FIG.

FIG. 4 is a flowchart showing the operation of FIG.

5 is a flowchart showing the operation of FIG.

FIG. 6 is a timing chart of FIG.

FIG. 7 is a diagram showing a conventional example of an intercommunication device.

FIG. 8 is a diagram showing a conventional example of an intercommunication device.

FIG. 9 is a diagram showing a conventional example of an intercommunication device.

[Explanation of symbols]

11 First control device 12 Second control device D ₁ , D ₂ communication line 21 ROM 22 Timer 23 CPU

Claims (1)

[Claims] 1. An intercommunication device of control devices, wherein control data is communicated between a plurality of control devices.
The control data transmission unit of each control device has a conversion unit for converting the control data into an output time and a predetermined time interval.
For outputting a timekeeping start signal composed of two pulse signals, and for ending the timekeeping composed of two pulse signals having a predetermined time interval after the output time has elapsed since the second pulse signal of the timekeeping start signal was output. Output means for outputting a signal is provided, and when the second pulse signal of the timing start signal is input to the control data receiving section of each control device, timing is started and 1 of the timing end signal is output. An intercommunication device for a control device, comprising: a clocking unit that terminates clocking when a second pulse signal is input; and a reading unit that reads control data based on the clocked time.