JPS6344266A - Data transmission system - Google Patents

Abstract

PURPOSE:To simplify the connection between a control computer and plural control circuits by adding identification numbers to the control circuits and transmitting said numbers and data by a data system in common. CONSTITUTION:The identification numbers are added to the control circuits 20. In order to transmit data from the control computer 10, data transmitted to the control circuit 20, the identification number of the control circuit 20 to which said data is transmitted and the identification number of the control circuit 20 which receives said data are transmitted to a common bus 12. Each control circuit 20 decodes the identification numbers on the common bus 12, and decides whether it is specified or not. Only the specified control circuit 20 fetches or transmits the data.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a data transmission system between a central processing unit and a control circuit. It relates to data transmission between a control computer and a control circuit in a system that controls operations.

2. Description of the Related Art Conventionally, robots, machine tools, etc. have mainly been controlled by independently controlling the position and speed of each drive shaft to a target value. For this position control and speed control, for example, while receiving the target value of each axis, receiving the detected data of the position (angle) and speed of the drive shaft, and controlling the current of the drive motor based on the deviation value between the two. A circuit configured with a feedback loop is used, and its control is generally carried out by PI control or PID control.

In recent years, control of robots, machine tools, etc. requires high precision in position and speed.

Furthermore, as robots, machine tools, etc. become more complex, the position of one drive shaft has come to influence the dynamic characteristics of other drive shafts. FIG. 3 shows a manipulator arm as an example of such a robot, and the position of the hand changes depending on the rotation of motor A and motor B. FIG. Further, depending on whether the hand is positioned horizontally or vertically, the force acting on the contact sensor of the hand changes, and it becomes necessary to adjust the gripping force of the hand accordingly.

However, as mentioned above, with conventional control methods that only control each control axis independently, it has become difficult to control robots, machine tools, etc. whose movements are related to each other with high precision. ing.

For this reason, a digital control system has been adopted in which data such as the position and speed of each drive shaft is concentrated in a control computer, and the computer centrally controls each drive shaft based on the collected data.

Problems to be Solved by the Invention In such a digital control system, various data such as position and speed regarding each drive shaft is sent to a computer,
On the other hand, a transmission line is required to send the control data determined by the computer based on the data to each control circuit.

If such a transmission line is installed independently between the computer and each control circuit and each sensor as shown in Figure 2, not only will the wiring be troublesome, but the total length of the line will be enormous. . The amount of wiring increases as the number of controlled axes increases.

Furthermore, in the configuration shown in FIG.
It outputs control data independently to each control circuit and receives measurement data independently from each sensor.

Therefore, the acquisition of various data and the transmission of control data were not efficient.

Therefore, an efficient connection method is desired in terms of the amount of wiring between the control computer and the control circuit.

Therefore, the present invention aims to provide a data transmission system between a control computer and a control circuit, etc., which solves the above-mentioned problems.

Furthermore, it is an object of the present invention to provide a data transmission method that can simplify the connection between a control computer and each control circuit and reduce the time required for data transmission.

Means for solving the problem, according to the present invention, includes a central processing unit, a common bus coupled to the central processing unit, and a plurality of control circuits coupled in parallel to the common bus. In a data transmission method for a control system equipped with The data is sent onto the common bus in a form that includes the data to be sent to and the identification number of the control circuit that wants to receive the data, and each control circuit decodes the identification number on the common bus and determines whether it has been designated or not. It is determined whether or not the specified control circuit receives or transmits data.

Function: The data transmission system according to the present invention as described above transmits data using a common bus system. Therefore, the line between the central processing unit and the control circuit is greatly simplified, and additional control circuits can be added without increasing the number of lines.

Further, according to the data transmission system of the present invention, when transmitting data from the central processing unit, not only the control circuit to which the data is to be transmitted is specified, but also the control circuit to which the data is to be received afterward is specified.

The control circuit that receives the transmitted data decodes the received data and determines whether it has been designated. As a result, if it is the destination of the transmitted data, it takes in the data and executes the necessary control operations. On the other hand, if the control circuit itself is the one requested to transmit, it transmits the requested data to the central processing unit after the central processing unit has finished transmitting the data. In this way, since transmission requests are not output independently, the time required for data communication can be reduced.

EXAMPLE Hereinafter, an example of a data transmission system according to the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a diagram showing a system configuration between a control computer and each control circuit in the data transmission system of the present invention.

The central control computer 10 has an interface circuit 1
6, a common data bus 12 and control lines 14A and 1
It is connected to 4B. A plurality of control circuits 20 are coupled to the common data bus 12 and control lines 14A and 14B via interface circuits 18, respectively. These control circuits 20 are given different identification numbers or addresses for each control circuit. A control signal indicating that data has been transmitted from the computer 10 to each control circuit 20 is transmitted to the control line 14A.
0, and on the other hand, each control circuit 2 is sent to the control line 14B.
A control signal indicating that data has been transmitted from the computer 10 to the computer 10 is sent from each control circuit 20.

Data transmission from the computer 10 is performed in a data format as shown in FIG. 4, for example. That is, for example, of a transmission data unit consisting of a total of 16 bits, the first 4 bits are the identification number (A) of the destination control circuit, and the next 4 bits are the control circuit to be received, that is, to request data transmission. This is the circuit identification number (B), and the latter 8 bits are transmission data to be transmitted to the control circuit with the identification number (A).

In the data transmission system as described above, when the computer 10 sends data, the interface circuit 1
Data having a configuration as shown in FIG. 4 is output to the common bus 12 via the bus 6. On the other hand, a control signal indicating that data has been transmitted from the computer 10 to each control circuit 20 is output to the control line 14A.

As a result, each control circuit 20 receives transmitted data and control signals via its associated interface circuit 18, and uses the control signals to decode data on the common data bus. That is, the identification number data (A) and (B) are decoded to determine whether the control circuit is a control circuit that receives or receives data or a control circuit that is requested to send data.

If it corresponds to a control circuit that receives and receives data,
It takes in the transmitted data on the common bus and uses it to control the drive of motors, etc. in the control circuit. If it corresponds to a control circuit that is required to send data, it prepares the transmission data on the common bus 12 after the transmission data from the computer, outputs a control signal on the control line 14B, and sends the data to the computer. Interrupt processing is applied to 10. If the control circuit is neither a control circuit that receives or receives data nor a control circuit that is required to send data, the control circuit does not respond to the transmitted data.

After sending data, the computer 10 immediately executes the next processing operation, and data from each control circuit can be received by interrupt processing, and the time spent waiting for data input can also be used for calculation processing. can do.

FIG. 5 shows a specific example of the configuration of an interface circuit on the control circuit side of the data transmission system as described above. In the illustrated embodiment, a circuit for controlling the DCC morph is realized using the method of the present invention. Here, an example of a software servo method is shown in which all current values given to the motor are calculated. Even when the servo control circuit is configured with an analog amplifier or when a pulse motor is used, if the interface circuit is configured in the same way, it can be used without any problem.

Computer 10 is coupled directly to control lines 14A and 14B and is connected to common bus 12 through register 16A, which constitutes interface circuit 16.

The register 16A is connected to the control lines 14A and 14B, and is controlled by control signals on the control lines L4A and 14B to register transmission data from the computer 10 and output it to the data common bus 12. , the data on the data common bus 12 is registered and the computer 10
It works to output to .

Each control circuit 2OA, 20B, ... has a common bus 12
and a receiving register Rr connected to the control line 14A;
It has a transmission register Rt connected to the common bus 12. Then, of the data output from the receiving register Rr, the part corresponding to the identification number (A) in FIG. 4 is output to the decoder D+ and decoded, and the identification number (A) indicates the self. If so, put the D/A converter into operation. Therefore, the D/A converter receives a portion of the data output from the reception register Rr that corresponds to the transmission data in FIG. 4, and performs D/A conversion. That D
The output of the /A converter is amplified by an amplifier A and output to the motor M,
is output to.

The angle and position of the controlled member driven by the motor M1 are detected by an encoder E and outputted to a counting circuit C. The output of the counting circuit C is connected to the transmission register Rt.

Furthermore, of the data output from the reception register Rr,
The part corresponding to the identification number (B) in FIG. 4 is output to the decoder D2 and decoded, and if the identification number (B) indicates self, the control logic circuit is operated. . The control '+80 sick circuit is the control line 14B.
At the same time, it operates the transmission register Rt to take the contents of the counting circuit C into the transmission register Rt and output it to the common bus 12.

In such a configuration, the computer 10 controls each motor M
Calculate the control amount to be given to l , M2 , .

For example, if speed control is performed using normal PI control,
The target angular velocity ω is the current angular velocity. However, it is calculated using the formula K1, K2 = coefficient. This data is used as the transmission data in FIG. 4, and the identification number of the control circuit of the motor M1 is the identification number (A
) to configure the transmission data.

Furthermore, for example, a motor M to be controlled next to this motor M1
In order to know the current angular velocity of the motor 12, the transmission data is constructed by adding the identification number of the control circuit of the motor 12 as the identification number (B) of the control circuit to be received in FIG.

Such data is output onto the common bus 12 and the control line 14.
When a control signal is output to A, each control circuit takes in the data on the common bus 12 into the reception register Rr. Among them, the control attached to motor M1 (sum circuit 2OA
decodes two identification numbers (A) and (B) using decoders D1 and D2, and since the first identification number (A) designates itself, the transmission data is manually input to the D/A converter. The D/A converter converts the transmission data into analog data and outputs it to the motor M1 through the amplifier A.

On the other hand, in the control circuit 20B attached to the motor M2, the identification numbers (A) and (B) are determined by the decoders DI and D2.
Since the latter identification number (B) specifies itself, the logic circuit for transmitting the data is operated. This logic circuit sets the data of the counting circuit C in the register Rt and sends the data to the control computer.
Send control signals.

Through the above processing, the computer can obtain data on the next motor to be controlled, and can immediately calculate the control current value for motor M2.

In the above explanation, after sending the control data of motor M1,
The computer 10 waits for human power data from the motor M2, and after receiving the data, performs control calculations. However, for example, if the data for motor M2 is received by issuing a reception request when sending the control data for motor M0, which is one motor before motor M1, then immediately after sending the control data for motor M1. It is possible to control and calculate M2. Transmitted data from (for example) motor M3, which issued a reception request when transmitting control data to motor M1, can be received by interrupt processing, and after transmitting data, the next data can be sent without waiting time. calculation processing becomes executable.

Effects of the Invention As is clear from the above explanation, with the data transmission method according to the present invention, the control circuit number of the destination and the control circuit from which data is desired to be received can be arbitrarily set, and the processing time involved in data reception can be set as desired. can also be used without waste,
Efficient data transmission becomes possible.

[Main reference number]

10... Computer 12...Common bus 14A, 14B...control line 16.1B...interference circuit 20...control circuit

Claims (2)

[Claims] (1) In a data transmission method in a control system comprising a central processing unit, a common bus coupled to the central processing unit, and a plurality of control circuits coupled in parallel to the common bus, Each control circuit is given an identification number, and when transmitting data from a computer, the identification number of the control circuit to which you want to send the data, the data to be sent to that control circuit, and the number of the control circuit to which you want to receive data. Data is sent out on the common bus in a form that includes an identification number, and each control circuit decodes the identification number on the common bus, determines whether it has been designated, and transmits the data only to the designated control circuit. A data transmission method characterized by importing or transmitting data. (2) The sending data includes an identification number of a control circuit to which data is to be transmitted, an identification number of a control circuit to which data is to be received,
The data transmission system according to claim (1), characterized in that the data transmission system is configured in the order of transmission data.