JPS6232739A - Switching control system - Google Patents

Abstract

PURPOSE:To prevent the titled system from misconnection by a waiting the changing of connection between a communication control part and a circuit connection part connected at the rate of (1 to 1) until another circuit connection part connected to a newly connected communication control part is separated. CONSTITUTION:The communication control parts A1-A3 are connected to the circuit connection parts C1-C3 at the rate of (1 to 1) by exclusively using respective buses B1-B3 on the basis of a command outputted from a system control part D. When the control part D instructs so that the communication control parts A3, A1 are connected to the circuit connection parts C1, C3 respectively, the circuit connection parts C1, C3 release the buses B1, B3 respectively. When detecting the disconnection of the circuit connection part C3 the communication control part A3, the circuit connection part C1 is connected to the bus B3, and after releasing the circuit connection part C1 from the communication control part A1, the circuit connection part C3 is also connected to the bus B1. Consequently, the system can be simply prevented from malfunction due to double connection.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a switching control system for changing connections between devices. In particular, the present invention relates to a switching control method when only an exclusive connection is allowed, such as because the connection between a control device and a controlled device has a bus structure.

〔overview〕

The present invention provides, in a switching control method where only an exclusive connection is permitted due to a bus structure or the like, the connection between a control device and a controlled device, when an instruction is given to change the connection of the system control device, The control of the system control device becomes complicated by disconnecting the control device that was previously connected to the controlled device and waiting until the other controlled device is disconnected before connecting the newly connected control device. This is designed to eliminate malfunctions and destruction of circuit elements due to double connections.

[Conventional technology]

FIG. 3 is a block diagram of the switching control device.

In FIG. 3, A1-A3 are communication control units; B;

~B is a bus, C8 to C3 are line connection units, and D is a system control unit.

Conventionally, as an example of switching control, switching control has been performed between a communication control section, which is a control device, and a line connection section, which is a controlled device. As shown in FIG. 3, one of the control devices AI to A:l is a spare and can be used as a substitute in the event of a failure in another control device.

One of the controlled devices Cl-Ca1 is a test device equipped with a test line for checking the function of the control device. Control device A+-Az and controlled devices C, -C3 are connected to buses B1 to B.
3, and each controlled device Cr'C's is connected exclusively to bus B by instructions from the system controller.
.

~B3 and operates logically.

When the active device of the control device A I-A s fails, the system control device designates the control device A to be newly connected to the controlled device C, and connects the backup control device and the controlled device that was connected to the failed control device. In addition, the fault control device and the test controlled device are connected respectively.

[Problem that the invention seeks to solve]

However, in such a conventional switching control method, two controlled devices are temporarily connected to a certain bus.
There are drawbacks such as malfunction of the control device or controlled device and destruction of circuit elements. Additionally, in order to prevent multiple controlled devices from connecting to a bus, there is a method in which a neutral state is established in which the controlled device is not connected to any bus, and the system controller issues an instruction regarding the neutral state. However, there was a drawback that the control of the system control device such as order control or neutral instruction became complicated.

The present invention solves the above-mentioned drawbacks, and aims to provide a switching control method that does not complicate the control of a system control device, and does not cause malfunctions or destruction of circuit elements due to the dual structure.

[Means for solving problems]

The present invention includes a plurality of control devices (A+, Az, Az)
, a plurality of controlled devices (CI, C2, C1) each connected to the plurality of control devices, and a system control device (D) that controls connections between the plurality of controlled devices and the plurality of control devices. In a switching control method including a switching control circuit that selects and connects the plurality of control devices based on instructions from the system control device, the switching control circuit includes a switching control circuit that selects and connects the plurality of control devices based on instructions from the system control device, Detection means for detecting that no other controlled device is connected to the newly connected control device after disconnecting the connected control device based on an instruction to change the connection of the control device; The apparatus is characterized in that it includes a connecting means for connecting to the newly connected control device according to a detection signal of the means.

[Effect]

According to the present invention, when an instruction is given to change the connection of a system control device, the connected control device is disconnected, and another controlled device is connected to the control device to be newly controlled by the detection means of the controlled device. If it is connected, it waits until the connection is disconnected, and when it detects that it is not connected, it connects to the newly connected control device using the connection means. This prevents the control of the system control device from becoming complicated, and prevents malfunctions and destruction of circuit elements due to double connections.

〔Example〕

Embodiments of the present invention will be described with reference to the drawings.

The overall configuration of the switching control device is similar to the conventional device described in FIG. This controlled device is the line connection section Cl-
03 is provided with a switching control circuit which is a feature of the present invention.

FIG. 1 is a block diagram of a switching control circuit of a controlled device of a switching control device according to an embodiment of the present invention. In FIG. 1, a connection destination control device number from a system control device (not shown) is connected to a register 1 and stored therein. Further, a connection change instruction is connected to the flip-flop 2 and set. The destination control device number from register 1 is connected to the input of decoder 3.4.

The flip-flop 2 is set and rlJ is connected to the control input of the decoder 3 via the signal line 11, and the decoding result from the decoder 3 is connected to one input of the AND gate 5. Three signal lines 10 corresponding to bus B shown in FIG. 3 are connected to other inputs of AND gate 5, respectively. If there is a controlled device C connected, its signal line 1
0 becomes "1". The output of each AND gate 5 is connected to an OR gate 60 input, respectively. or gate 6
The inverted output of is connected via signal line 12 to the reset input of flip-flop 2 and to the control input of decoder 4. When there is a controlled device C connected to the newly connected control device A, “1” from the AND gate 5 is connected to the input of the OR gate 6, and the OR gate 6
Since "0" is connected to the reset input of the reset 2 of the flip-flop 2 and the control input of the decoder 4,
Flip-flop 2 is not reset and decoder 4 is inactive. When the controlled device C connected to the newly connected control device A disappears, the output of the OR gate 6 becomes rlJ, the flip-flop 2 is reset, and the output of the OR gate 6 becomes “rlJ” regardless of the state of the signal line 10. 1'', and the decoder 4 becomes active. The decoding result "1" from the decoder 4 sets the signal line 10 corresponding to the designated control device A to "1" via the gate 7. Also, the interface signal with the designated control device A via the signal line 10 is enabled.

The operation of the switching control device having such a configuration will be explained.

FIG. 2 is an operation time chart of the switching control device of the present invention. Control devices A1 to A shown in FIG.

The control device A is connected to the controlled devices C1 to C3.

The operation corresponding to a connection instruction from the system control device is shown with the control device A2, the controlled device C2, the control device A:l, and the controlled device C1 in the initial state.

(2) In response to a connection instruction from the control device A to the controlled device CI, the controlled device C1 opens the bus B1.

(2) In response to a connection instruction from the control device A to the controlled device C3, the controlled device C3 opens the bus B3.

At this time, the controlled device C3 is connected to the newly connected control device A.
Knowing that the controlled device C1 is not connected to bus B1, it connects to bus B1.

■ By the controlled device C3 opening the bus B3,
The controlled device CI knows that the controlled device C3 is not connected to the control device A3, and connects it to the bus B3, which was waiting for the controlled device C3.

As described above, a plurality of controlled devices C are not connected to the bus at the same time, and control from the system control device does not require orderliness or instructions to a neutral state.

Next, referring to FIG. 1, a description will be given of means for determining whether or not another controlled device C is connected to the control device A to which the controlled device C is newly connected. FIG. 1 is a block diagram of a control bus 10 connecting at least all of the controlled devices C and a switching control circuit connected to the control bus 10 and included in all the controlled devices C. Register 1 stores a new connection destination control device number from the system control device, and flip-flop 2 is set by a connection change instruction from the system control device. The decoders 3.4 each have a signal line 11.
When 12 is "1", the decoding result is output. In addition, the three signal lines 10 are buses B, ~B, respectively, shown in FIG.
, and there is a connected controlled device C, "
1". When a connection change instruction is given, the connection destination number is stored in register 1, and flip-flop 2 is also
is sent, and decoder 3 becomes active. At this time, an AND gate 5 and an OR gate 6 check whether there is a controlled device C connected to the newly instructed control device A. If there is a controlled device C connected, the output of the OR gate 6 (signal line 12) is "0", the decoder 4 is deactivated, and the flip-flop 2 is kept at "1".

In other words, in this state, it waits until the controlled device C connected to the designated control device A disappears. Signal line 1
When the signal corresponding to the specified control device A becomes “0” (that is, there is no controlled device C connected to the specified control device A), the output of the OR gate 6 becomes r.
lJ, the flip-flop 2 is reset, the decoder 3 becomes inactive, and the output of the OR gate 6 is kept at "l" regardless of the state of the signal 8310. Further, the decoder 4 becomes active and sets the signal line 10 corresponding to the designated control device A to "1" via the gate 7.

The signal line 13 is a signal for validating the interface signal with the designated control device A, and this signal connects the controlled device C to the bus B corresponding to the control device A.

〔Effect of the invention〕

As explained above, the present invention does not require complex control such as order control or neutral instruction in the system control device, and has an excellent effect of preventing malfunctions and destruction of electronic circuits due to double connections. be.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a switching control circuit of a controlled device in a switching control device according to an embodiment of the present invention. FIG. 2 shows an operation time chart 1 of the switching control device of the present invention.
. FIG. 3 is a block diagram of the switching control device. l...Register, 2...Flip-flop, 3.4
... Decoder, 5 ... AND gate, 6 ... NOR gate, 7 ... Gate, 10 to 13 ... Signal line, A
I"" A 3...Communication control unit (control device), B+
783...Bus, C8-C1...Line connection unit (controlled device).

Claims (1)

[Claims] (1) A plurality of control devices (A_1, A_2, A_3),
A plurality of controlled devices (C_1, C_2, C_3) each connected to the plurality of control devices, and a system control device (D) that controls the connection between the plurality of controlled devices and the plurality of control devices. In a switching control method, the plurality of controlled devices includes a switching control circuit that selects and connects the plurality of control devices based on instructions from the system control device, and the switching control circuit is configured to control the system control device. a detection means for detecting that no other controlled device is connected to the newly connected control device after disconnecting the connected control device based on a connection change instruction; and a detection signal of the detection means. and connecting means for connecting to the newly connected control device.