JPH0318149A - Data transmission network system - Google Patents

Abstract

PURPOSE:To allow each controller to participate in a network at optional time by returning a registration permitting command in response to a registration requesting command sent from each controller. CONSTITUTION:When other network controller 1j except one network controller 1i participates in a network, a switching means 22 connects the controller in series with a transmission line 4 to send a registration requesting command to the controller 1i. Thus, the controller 1i receivers a registration request from other controller 1j and registers the address of the controller to a storage area 14A and sends a registration permission command. Thus, the other controller executes the data transmission on the condition of the reception of the registration permitting command.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a data transmission network system.
In detail, this article relates to a data transmission network system that allows each network controller to participate in the network at any time. [Prior Art] Figure 8 shows a conventional data transmission network system. This includes a plurality of network controllers 101+ to 101 connected in a loop through a transmission line 104.
．． It is composed of. Each network controller 1
011 to 101, c connected through bus 111
puit2, ROM113, RAM114, I/011
5 and I/0116. ■/011
'5 is connected to a host computer or terminal. The transmission line IO4 is connected to I/0116. Each network controller 101. ~101. CP of
The U 112 takes in the command sent through the transmission line 104 via the I/0 116, and determines whether the address included in the command is its own address.
If it is not your own address, send the command to I/011.
6 to the next network controller (in FIG. 8, the counterclockwise network controller). On the other hand, if it is its own address, it executes the process for that command. [Problems to be Solved by the Invention] In the conventional system, since it has the above-mentioned configuration, all the network controllers 1011 to 101. , is functioning normally.

Therefore, each network controller 1011 to 101
, themselves are normal, a network will be constructed only after all network controllers 1011 to 101 are powered on. This means that each network controller 101
1-101. are located at remote locations, and all network controllers 10l1 to 101. If power cannot be supplied to all the network controllers 1011 to 101 at the same time, it takes time for all the network controllers 1011 to 101 to be powered on, so there is a problem that a network cannot be constructed during that time. SUMMARY OF THE INVENTION An object of the present invention is to solve these conventional problems and provide a data transmission network system that allows each network controller to participate in the network at any time. [Means for Solving the Problems] Therefore, in the present invention, in a data transmission network system including a plurality of network controllers connected in a loop through a transmission line and capable of mutually transmitting data, any one of the network controllers is , a storage area for storing the address of each network controller, and control for registering the address of the network controller in the storage area and then transmitting a registration permission command when a registration request command is received from any other network controller. and switching means capable of connecting the network controller in series to the transmission line and disconnecting the network controller from the transmission line and short-circuiting the transmission line; Means for transmitting a registration request command to the one network controller in a state where the controllers are connected in series in the transmission line, and receiving a registration permission command from the one network controller in response to the registration request command. and a control means having means for executing data transmission as a condition. [Operation] When network controllers other than one of the network controllers participate in the network,
After the network controllers are connected in series in the transmission line by the switching means, a registration request command is sent to the first network controller. Then, when one network controller receives a registration request command from another network controller, it registers the address of that network controller in its storage area, and then sends a registration permission command. This allows other network controllers to perform data transmission on the condition that they receive a registration permission command from one network controller. In other words, you can participate in the network. [Example] Hereinafter, the present invention will be described in detail based on an example not shown in FIGS. 1 to 7. Figure 7 shows the system of this embodiment. The system consists of a plurality of network controllers 1.1 connected in a loop through a transmission line 4 and capable of transmitting data to each other. ~
1o, any one of them is connected to, for example, a network controller 1l and is capable of transmitting data to the network controller 1, and a host computer 2 is connected to the network controllers 12 to 1fi, excluding any one of the network controllers l1. The network controller 12-1. Multiple terminals 3 capable of data transmission 211 3 *2-3,,3. ．．
It is composed of 2. FIG. 1 shows each of the network controllers 1l to 1.
The block diagram is shown. In the same figure, ll is CP
The CPU II, which is the
, I/015, I/016, communication I/017, above c
Watchdog timer 1 to check puit runaway
8 etc. are connected to each other. Note that even if the power is turned off, these circuits will continue to operate for a predetermined period of time (approximately 5
) is backed up by the battery 19, which means normal operation! It is designed to be continuous. Also, when the power is turned off, it is detected by the power failure detection circuit 20,
An interrupt signal is given to the CPU II. Here, in addition to a data storage area for storing data, the RAM 14 includes a data storage area for each network controller 11.
Address storage area 14A for storing addresses of ~11
is provided. The I/015 also includes the host computer 2? Each terminal 32■3■2~3ml+3
．． 2 can be connected. Also, the above 1/0
16 is connected to a control panel 2l on which an error lamp, a "READY" lamp, and other necessary keys and switches are arranged. Further, the transmission line 4 is connected to the communication I/017 via a switching means 22. The switching means 22 connects the communication I/017 in series to the transmission line 4, and receives a switching command from the CPU II based on the interrupt signal or a switching command from the watchdog timer 18 through the OR circuit 23. , a switching operation is performed to disconnect the communication I/017 from the transmission line 4 and short-circuit the transmission line 4. FIG. 2 shows the specific structure of the switching means 22. The switching stage 22 includes switches 31A and 31B provided respectively between the input measuring terminal 4A and the output side terminal 4B of the transmission line 4 and the input side terminal 17A and the output open terminal 17B of the communication I/017. , the switches 31A and 31 are turned on by energization.
An excitation coil 32 that energizes the input side terminal 17A and the output side terminal 17B of the communication I/017, and the CPU
a controller 33 that controls energization of the excitation coil 32 in accordance with switching commands from I and the watchdog timer 18;
The switch 31A. 31B is input (pl+@child 17A
and when the switch 31A returns to the direction away from the output measuring terminal 17B. 31B, and a short-circuit circuit 34 that short-circuits between 31B and 31B. Note that the CPU II executes the processes shown in the flowcharts shown in FIGS. 3 to 6 according to the program stored in the ROM 13. Here, CPUIl
The ROM 13 and ROM 13 constitute a control means for executing these processes. Next, the operation of this embodiment will be explained with reference to the flowcharts of FIGS. 3 to 6. When constructing a network, a network controller (main network controller) that has control over the entire network is required.
The condition is that there is one. Here, assume that network controller 1. is the main network controller, and other network controllers 12 to l. We will proceed with the explanation assuming that is a subnetwork controller. (Main network controller) The CPU 11 of the main network controller 1 is
When the power is turned on, processing is executed according to the flowchart shown in FIG. 3, and when an interrupt signal is given from the power failure detection circuit 20, processing according to the flowchart shown in FIG. 4 is executed. First, when the power is turned on, initial processing is performed in step (hereinafter abbreviated as ST) 1 in FIG.
For example, connect the switches 31A and 31B of the switching means 22 to terminal 1.
After switching to 7A and 17B, proceed to ST2 and perform self-diagnosis processing. For example, the RAM 14 and ROM 13 are checked, and the voltage level of the backup battery of the RAM 14 is checked. Next, the process proceeds to ST3 and transmits a loop initial command to the transmission line 4, and waits for reception of the loop initial command in ST4. Here, if the loop initial command is received, that is, if it is confirmed that the network has been constructed, the process proceeds to ST5, where the "READY" lamp on the control panel 21 lights up, and then the process proceeds to ST6, where the sub-network controllers 12 to 1. Determine whether or not a registration request command has been received from. If the registration request command is received in ST6, the process proceeds to ST7 and it is determined whether or not the address included in the registration request command exists in the address storage area 14A. If there is no corresponding address, proceed to ST8 and register the address included in the registration request command in the address storage area 14A, then proceed to ST9 and send a registration permission command to the network controller that sent the registration request command.
Return to T6. In addition, if there is a corresponding address in ST7, S
After the TIO sends the registration refusal command to the network controller that sent the registration request command, the process returns to ST6. If the registration request command is not received in ST6, the process advances to STII and the subnetwork controllers 12 to 1. Determine whether a registration cancellation command has been received from. If a registration cancellation command has been received, ST1
Proceed to step 2 to cancel the corresponding address from the address storage area 14A, then proceed to ST13, send a cancellation completion command to the network controller that sent the registration cancellation command, and then return to ST6. Further, if the registration cancellation command is not received in ST11, the process proceeds to ST14, and data transmission processing, that is, the original data transmission work is executed. On the other hand, if an interrupt signal is received during these processes, the process proceeds to ST21 in FIG. 4, where a command to relinquish control is transmitted, and in ST22, one of the subnetwork controllers 12 to 1. Waits for a command to accept control from. When the control right acceptance command is received, that is, when it is confirmed that the control right has been accepted by one of the subnetwork controllers, the process proceeds to ST23, and a registration cancellation command is sent, and in ST24, the network controller to which the control right has been transferred ( In this case, wait for the cancellation completion command from (this will become the main network controller from now on). Here, when the cancellation completion command is received, ST? 5, the switching means 22 is turned off. That is, the excitation coil 32 is de-energized via the controller 33. Then, switches 31A and 31B are connected to terminals 17A. 1
7B and is short-circuited through the short-circuit circuit 34. As a result, the network controller 1 in which the abnormality has occurred is disconnected from the transmission line 4, and the transmission line 4
The network is maintained normally because it is short-circuited. At the same time, since the control right is transferred to another network controller, the network controller 11 functions as a sub-network controller when it rejoins the network. (Subnetwork controller) CPUI of each subnetwork controller 1~17
When the power is turned on, I executes the process according to the flowchart shown in FIG.
When an interrupt signal is given from , the process shown in the flowchart shown in FIG. 7 is executed. First, when the power is turned on, initial processing is performed in step (hereinafter abbreviated as ST) 31 in FIG.
terminals 17A, 17B! ,: After switching, S T 3
2 F3 (Perform self-diagnosis processing. For example, RAM1
4 and ROM13, and check the voltage level of the backup mt battery of RAM14. Next, the process advances to ST33 and after transmitting a registration request command to the transmission line 4, the process advances to ST34 and ST35 to wait for a registration permission command or a registration refusal command from the main network controller 1. When the registration refusal command is received in ST35, the process proceeds to ST36, where the error lamp on the control panel 21 is turned on, and then the switching means 22 is turned off, and the process ends. Therefore, in this case, you cannot participate in the network. Also, in ST34, when the registration permission command is received, the process advances to ST38 and the “RE” on the control panel 2l is
After lighting the "ADY" rung, it is determined in ST40 whether or not a control right relinquishing command has been received.If the control right relinquishing command has not been received, the process advances to ST41 and the original data transmission operation is executed. , it is possible to participate in the network, that is, to execute the original data transmission task, on the condition that it has received a registration permission command from the main network controller 1.Furthermore, if it has received a control right relinquish command in ST40, ST4
After proceeding to ST 2 and transmitting a control right acceptance command to the main network controller 11, proceeding to ST43 and performing processing as the main network controller, that is, S in FIG.
Processes T6 to ST14 and S721 to ST2 5 in FIG. 5 are performed. Therefore, if a failure occurs in the main network controller 11 and it relinquishes control, any of the other subnetwork controllers l2 to 1
．． takes over the control rights and functions as the main network controller. On the other hand, when an interrupt signal is given from the power failure detection circuit 20, the process proceeds to ST51 in FIG. 6, transmits a registration cancellation command, and waits for a cancellation completion command from the main network controller 1l in ST52. Upon receiving the cancellation completion command, after turning off the switching stage 22,
finish. Therefore, in this case as well, the network controller in which the abnormality has occurred is disconnected from the transmission line 4, and the transmission line 4 is short-circuited, so that the network is maintained normally. Therefore, according to this embodiment, a plurality of network controllers 11 to l. If an abnormality occurs in any one of the network controllers, that network controller is disconnected from the transmission line 4 and the transmission line 4 is short-circuited, so even if a failure occurs in the network controller, It is possible to maintain normal network functions. In addition, a network controller 1. which has control authority over the network. Other network controllers excluding 12~
l. is the address of the network controller l
Since each network controller can participate in the network at any time, for example, each network controller can participate in the network at any time. Even if the network controllers are located far apart and power cannot be supplied to all network controllers at the same time, a network can be constructed simply by turning on the power to the necessary network controllers. In addition, if an abnormality occurs in the network controller 11 that has the right to control the network, the control right is transferred to another network controller and that network controller functions as the main network controller from now on. It is possible to maintain normal network functions even in the case of [Effects of the Invention] As described above, according to the present invention, each network controller can join the network at any time. This eliminates the inconvenience of not being able to construct a .

[Brief explanation of the drawing]

Figures 1 to 7 show one embodiment of the present invention.
Figure 2 is a block diagram showing each network controller, Figure 2 is a diagram showing the switching means, Figure 3 is a main flowchart in the main network controller, Figure 4 is a flowchart of interrupt processing in the main network controller, and Figure 5 is a diagram showing other network controllers. Figure 6 is a flowchart of interrupt processing in another network controller.
Figure 7 is a block diagram showing the entire system. Figure 8 is a block diagram showing a conventional system. 11-1. ...Network controller, 4...
Transmission line, 11.13...CPU and ROM 14A...Address storage area, 22...Switching means. (control means)

Claims (1)

[Claims] (1) In a data transmission network system comprising a plurality of network controllers connected in a loop through a transmission line and capable of transmitting data to each other, any one of the network controllers has a storage area for storing the address of each network controller. and a control means for registering the address of the network controller in the storage area and then transmitting a registration permission command when receiving a registration request command from any of the other network controllers, each of the other network controllers , switching means capable of connecting the network controller in series to the transmission line, disconnecting the network controller from the transmission line, and short-circuiting the transmission line; and a switching means capable of connecting the network controller in series to the transmission line; control means having means for transmitting a registration request command to the one network controller in the state, and means for executing data transmission on condition that a registration permission command is received from the one network controller in response to the registration request command. A data transmission network system comprising: