JPH0270142A - Method for controlling communication - Google Patents

Abstract

PURPOSE:To construct a system with high reliability by controlling control state information and answer time information. CONSTITUTION:A controlled terminal equipment 2 which has received a control command 3 from a control side terminal equipment 1 executes a control processing and simultaneously defines state information and time information of a reception processing. The equipment 1 designates control state information and answer time information at a memory address designation frame 4, and the equipment 2 stores them in a transmission buffer. The equipment 1 subsequently, reads data, a frame 5 reads information stored in the transmission buffer and the equipment 2 recognizes that a system is in the middle of the normal execution of the command. The system waits for the necessary minimum time for command processing (t) of the equipment 2 from answer time information, control result information with respect to the command 3 in the equipment 2 is designated by a memory address designation frame 6, and a data read frame 7 reads the information. Thus, the system with high reliability can be constructed by recognizing whether the command 3 which the equipment 1 expects to transmit to the equipment 2 has accurately been processed or not.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a device control method in a data communication network between terminal devices.

BACKGROUND ART A device control method according to a conventional technique will be explained based on the drawings. FIG. 2 shows the configuration and connection status of conventional terminal equipment.

Each terminal device has a communication control device, and the respective communication control devices are connected to each other via a communication line 8. Each communication control device manages control result information of each terminal device. This control result information means the control status status of the own terminal device; for example, if the terminal device is currently powered off,
Indicates information such as playback status and stop status. In the drawing, the numbers in parentheses indicate the value of the bus address on the communication line of each communication control device, and the numbers in parentheses () indicate the value of the memory address that this control result information has within the communication control device. . A communication frame on the communication line 8 is shown in FIG. S.B.
indicates a start bit and represents the beginning of a communication frame.

MB is a mode pit indicating the mode of this frame. That is, since the frame speed and maximum number of transmission bytes are different for each mode, this indicates which mode the frame belongs to. MA is the master address, which is the source address of the frame, SA is the slave address, which is the destination address of the frame, and the CF Lt control field indicates the attributes of this frame. A data section follows the control field, and indicates data to be sent and received.

This data section is defined to have a variable length in bytes.

Here, the contents of the control field are shown in FIG.

WMA indicates writing of a memory address and is used to notify the other party's communication control device of the address value of the memory to be read.

WC indicates command writing, and WD indicates data writing. RD indicates data reading and is used when reading data from the other party's communication control device. R8S is used to read the status of the other communication control device, and RLA is used to read the address of the communication control device that is locking the other communication control device. FIG. 5 shows a device control sequence in the communication system as shown in FIG. 2.

Here, the communication control device (2) transmits a control command to the communication control device (2), and then reads out the control results. 〉The numbers in parentheses indicate the bus address of each communication control device. First, the communication control device ■ is connected to the communication control device ■ (a
) send control commands. The communication control device (2) that receives this command controls the terminal device (2) according to the contents of the command, and secures the control result as control result information. The communication control device (a) sends a control command and, after T time, specifies a memory address for control result information to the communication control device (b) sends a memory address designation frame. The communication control device (b) stores the contents of the memory address indicated in the memory address designation frame, that is, the control result information, in its own transmission buffer, and prepares for the next readout of the information. Next is the communication control device■
sends a (C) data read frame to the communication control device ■. Communication control device that received this frame■
The control result information that was previously stored in the transmission buffer is read out. Control between each communication control device and the terminal equipment is performed using such a series of sequences.

FIG. 6 shows the data contents of frames transmitted and received between communication control devices.

'11'1 in the MA section indicates the bus address value of the communication control device ■, and PA12” in the SA section indicates the bus address value of the communication control device ■. SB and MB are omitted here. (a)
The CF in the control command frame uses the command write code ``wc''.

(b) CF in the memory address frame is the memory address write code “WMA” (C) CF in the data read frame is the data read code “RD”
” are used respectively.

Problems to be Solved by the Invention In the control sequence of FIG. 5 shown in the conventional example, the communication control device ■ (a) sends a control command until (b) sends a memory address designation frame. The time interval T varies depending on the destination communication control device and the control command to be transmitted. That is, it cannot be uniquely determined how long it will take for the communication control side that receives the command to complete processing of the received command. Therefore, the time interval T on the sending side
must take the largest value that can be expected in the system. However, as shown in Fig. 5, (a) if the communication control device (2) that has received the control command does not require the processing time TIL required for that command, the time T-T1 = T2 becomes a wasted waiting time. . That is, the throughput of the system operating with this control sequence is reduced. Also(
a) When an abnormal state occurs in the communication control device (2) that has received the control command, the control result information read by the communication control device (2) does not necessarily indicate the correct value.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention newly manages control state information and response time information, and determines the processing execution state of the terminal device in response to received control commands,
The time information required for the processing can be read from the side that sent the control command. It is intended to do so.

Effect of the Invention With the above configuration, the present invention allows the controlling side communication control device to read the control result information of the controlled side communication control device in the minimum necessary time, thereby improving the throughput of the system. Furthermore, by reading out the control status information, abnormal conditions can be detected, and correct control result information can always be read out.

Embodiment FIG. 1 shows a device control sequence according to the present invention. Consider a case where the controlling terminal device 1 controls the controlled terminal device 2. The controlling terminal device 1 first transmits a control command 3 to the controlled terminal device. The controlled terminal device 2 that has received this command starts controlling the terminal device according to the received command, and at the same time determines the status information of the receiving process and the time information required for the process. The controlling side terminal device specifies the memory address indicating the control state information and response time information in the memory address specification frame 4, and the controlled side terminal device specifies the contents of the control state information and response time information having the specified memory address. Store in the transmission buffer of the control side communication control device. Subsequently, the control side terminal equipment reads out the control state information and response time information stored in the transmission buffer of the controlled side communication control device using the data read frame 5. When the control side terminal device confirms that the controlled side terminal device is executing the command normally from the read control status information, the controlled side terminal device processes the command based on the read response time information. Waits for the minimum time t required for the control, then specifies a memory address indicating control result information for the control command at the controlled terminal device in the memory address designation frame 6, and reads that information in the data read frame 7. This makes it possible to confirm whether the control command sent from the controlling terminal device to the controlled terminal device has been correctly processed. The contents of the control state information are shown in FIG. This information makes it possible to know the processing status of the controlled terminal device in response to the control command. Here, running 13 indicates that the command is currently being processed, normal execution completed 14 indicates that the processing of the received command has finished, and not yet received 15
16 indicates that the control command itself has not been received, 16 indicates that the terminal device does not have the function to process the received command, and 17 indicates that the terminal device does not have the function of processing the received command. This indicates that the unrealized device 8, which cannot process the information at present, does not have the memory itself for this control state information. FIG. 7 is an embodiment of a system configuration showing the configuration and connection state of terminal equipment according to the present invention.

Each communication control device includes control status information 9, control result information 10,
The response time information 11 is shown below, and the numbers in parentheses () indicate the value of the memory address that each piece of information has in each communication control device. 〉The numbers in parentheses indicate the value of the bus address on the communication line 8 of each communication control device. FIG. 9 shows a control sequence when controlling the communication control device (2) and the terminal device (2) from the communication control device (2) and the terminal device (2) in this system. Further, frame data transmitted and received on the communication line 8 at this time is shown in FIG. Here SB1
MB is omitted. (d) shows the frame data of the device control command, (e) shows the frame data specifying the memory address of control state information and response time, and the data part shows the memory address (00, 00,
02). (f) is frame data for reading out control state information and response time information, and control state information, for example (in execution), response time information (1) is returned to the data section. (g) shows frame data specifying the memory address of the control result information, and specifies the memory address (01) of the control result information in the data portion. (h) is frame data for reading control result information, and the control result information is returned to the data section. The frame data shown in FIG. 10 shows the control sequence from communication control device ■ to communication control device ■, so all MAs are at address <11>S.
All A's indicate addresses 10>.

Note that all the communication control devices have the same functions, and control is mutually performed between all the communication control devices according to the control sequence according to the present invention.

Effects of the Invention As described above, the present invention improves the throughput of the system, and even if an abnormality occurs in the controlled terminal equipment, it is possible to easily recover from the error using correct information, resulting in a more reliable system. It can be constructed and is extremely effective in practical terms.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of an example of a control sequence according to the device control method of the present invention, Fig. 2 is a connection block diagram of a communication network and terminal equipment to which the conventional device control method is applied, and Fig. 3 is a communication line. Fig. 4 is a diagram showing the code of the control field of the frame in Fig. 3, and Fig. 5 is a diagram showing the control sequence according to the conventional device control method. , FIG. 6 is a diagram showing frame data transmitted and received in the control sequence of FIG. 5, FIG. 7 is a connection configuration diagram of a communication network and terminal equipment to which the device control method according to the present invention is applied, and FIG. 8 is a diagram showing the connection of the device. FIG. 9 is a diagram showing the contents of control state information, FIG. 9 is a diagram showing a control sequence according to the device control method of the present invention, and FIG. 10 is a diagram showing frame data transmitted and received in the control sequence of FIG. 9. Figure 1 Name of agent Patent attorney Shigetaka Awano (1 person) Figure 1 Funeral diagram Figure 1

Claims (6)

[Claims] (1) In a bus system in which terminal devices having communication control devices are connected to each other via communication lines, each communication control device has control status information and control result information, and any terminal device can communicate with other terminal devices. When controlling via the communication control device and the communication line, the control side terminal device transmits a control command to the controlled side terminal device, and the controlled side terminal device that received the control command transmits the control command. setting the control state information at the same time as starting the process;
On the other hand, the control side terminal device specifies the unique memory address that the control state information has in the communication control device using a memory address specification frame, and then receives the control state information from the controlled side terminal device using a data read frame. read out the control state information, determine the control result information, specify a unique memory address that the control result information has in the communication control device using a memory address designation frame, and then read the control result information using a data read frame. A communication control method for checking whether or not the controlled terminal equipment is correctly controlled by reading the information. (2) In a bus system in which terminal devices each having a communication control device are connected to each other via a communication line, when any terminal device controls another terminal device via the communication control device and the communication line. The controlling terminal device transmits a control command to the controlled terminal device, and then transmits a memory address designation frame for specifying a unique memory address possessed by the control status information in the communication control device on the controlled terminal device side. The control state information is read by sending a data read frame to the controlled communication control device, and if it is determined that the control state information is normal, then the control result information is By specifying a unique memory address in the controlled side communication control device using a memory address specification frame, and then reading out and determining the control result information using a data read frame, the controlled side terminal equipment can be controlled correctly. A communication control device that checks whether the communication has been carried out. (3) In a bus system in which terminal devices each having a communication control device are connected to each other via a communication line, when any terminal device controls another terminal device via the communication control device and the communication line. Each controlled side communication control device has control state information and control result information each having a unique memory address, and controls the terminal device based on a control command from the control side communication control device, and records the control state in the control state information. The state of the terminal device as a result of the control is managed as the control result information, and the information having which memory address is specified by the memory address specification frame received from the control side communication control device via the communication line. A communication control device that recognizes whether a memory address has been specified in the memory address designation frame and returns the content of the information having the memory address previously specified in the memory address designation frame using a data read frame also received from the control side communication control device. (4) In a bus system in which terminal devices each having a communication control device are connected to each other via a communication line, each communication control device has control status information, control result information, and response time information, and any terminal device When controlling another terminal device via the communication control device and the communication line, the controlling terminal device transmits a control command to the controlled terminal device, and the controlled terminal device receives the control command. The device sets the control state information at the same time as it starts processing the control command, and also sets the time required by the controlled terminal device to process the control command as the response time information, while the controlling terminal device sets the control state information as the response time information. specifying a unique memory address that the control state information and the response time information have in the communication control device using a memory address specification frame;
Next, the control state information and the response time information are read from the controlled terminal device using a data read frame, and the control state information is judged and the next step is performed at a time interval indicated by the response time information. By specifying a unique memory address that the control result information has in the communication control device using a memory address specification frame, and then reading the control result information using a data read frame, the controlled terminal equipment can be correctly controlled. Communication control method to check whether the communication has been carried out. (5) In a bus system in which terminal devices each having a communication control device are connected to each other via a communication line, when any terminal device controls another terminal device via the communication control device and the communication line. The controlling terminal device sends a control command to the controlled terminal device, and then specifies the unique memory address of the control status information and response time information in the communication control device of the controlled terminal device as a memory address. The control state information and the response time information are read by sending a data read frame to the controlled communication control device, and the control state information is determined to be normal. case,
After a time interval indicated by the response time information, the control result information specifies a unique memory address in the controlled communication control device using a memory address designation frame, and then uses a data read frame to specify the control result information. A communication control device that confirms whether or not the controlled terminal device is correctly controlled by reading and determining result information. (6) In a bus system in which terminal devices each having a communication control device are connected to each other via a communication line, when any terminal device controls another terminal device via the communication control device and the communication line. Each controlled side communication control device has control state information, response time information, and control result information having a unique memory address, and controls the terminal equipment by control commands from the control side communication control device and changes its control state. As the control state information, the state of the terminal device as a result of the control is set as the control result information,
A time interval until the control result information is finalized is managed as the response time information, and information having which memory address is specified by a memory address specification frame received from the control side communication control device via the communication line. A communication control device that recognizes the memory address and then sends back the contents of the information having the memory address previously specified in the memory address designation frame using a data read frame also received from the control side communication control device.