JPH0435247A - Maintenance system for daisy chain connection system - Google Patents

Abstract

PURPOSE:To remove a connector while other control section is in operation by allowing a control section to fetch the state of an input signal as operating information so long as an operation section indicates the validity of the operating information and it is consecutive for a prescribed period. CONSTITUTION:One operating section 11 and plural control sections 151 - 153 are in daisy connection and the operating section 11 sends prescribed operating information to the plural control sections 151 - 153 at monitor or maintenance. In this case, an operating information validity discrimination means 17 of the plural control sections 151 - 153 read the indication state of a validity indication means 13 of the operating section 11 and fetches an input signal as the operating information of the operating section 11 when the state is valid. When the indication state of the operating section 11 is invalid, a noise signal is cancelled and malfunction caused accordingly is avoided. Thus, when one of the plural control sections 151 - 153 is faulty, the connector is removed while operating the other control sections.

Description

[Detailed Description of the Invention] (Summary) Regarding a maintenance method for a system in which a plurality of control units are daisy-chained by a cable from one operation unit, if one of the plurality of control units breaks down, the other control units The purpose is to make it possible to remove the connector while the unit is still operating, and one operation unit and multiple control units are connected in a daisy chain, and the operation unit sends predetermined operation information to multiple control units during monitoring or maintenance. In a maintenance method for a daisy chain connection system, the operation section is provided with enable/disable instruction means for instructing a plurality of control sections to enable or disable the operation, and the plurality of control sections have enable/disable instruction means. The apparatus is configured to include operation information validity/invalidity determining means for determining whether the instruction is valid or invalid and further validating or invalidating the input signal when the state continues for a predetermined period.

[Industrial application field]

The present invention relates to a maintenance method for a system in which a plurality of control units are connected in a daisy chain via a cable from one operation unit.

[Conventional technology]

For example, in a system such as a financial computer system, where it is necessary to minimize the decline in service or the impact on business operations due to a failure or other abnormality in a single terminal device, multiple terminal devices may be installed in the same location. In many cases, even if one terminal device fails, another terminal device can take over the function.

On the other hand, the operation unit that monitors the control unit that controls each terminal device and performs predetermined operations on the control unit during maintenance is not used during operation, so providing it in common for each control unit saves space and costs. is planned. That is, in such systems, a plurality of control sections are often connected in a daisy chain to one operation section.

FIG. 5 is a block diagram showing a conventional configuration of a daisy chain connection system.

In the figure, an operation unit 51 and a plurality of control units 551 to 5
53 are connected in a daisy chain via cables 60 connected to each connector. In addition, each control unit 55. ~
55. The signal line is a pull-a knob, and the control unit 51
One end of the signal line is grounded in response to the operation of the key switch 53, forming an active low input level.

With such a configuration, the operation section 51 can be connected to the key switch 53.
The plurality of control units 55. It is now possible to send operation information all at once to 553.

[Problem to be solved by the invention]

By the way, if one of the plurality of control units breaks down, the connector to which the cable is connected is removed and inspection and maintenance is performed. In addition, in FIG. 5, a failure occurs in the control unit 55t,
The connection form in the degenerate operation state with the connector removed is shown by a broken line.

On the other hand, the operation unit 51 is used for system monitoring and maintenance, and does not operate during normal business operations (that is, does not access each control unit). Otherwise, the noise generated when disconnecting the cable cannot be detected even during business operations.
There was a possibility that it would malfunction as a command from Therefore, in the conventional daisy chain connection system, in preparation for such a case, it is essential to turn off the power to all control units and then disconnect the cable of the failed control unit.

The present invention provides a maintenance method for a daisy chain connection system that makes it possible to remove a connector while keeping the other control units operating when one of a plurality of control units daisy chain connected to an operation unit fails. The purpose is to

(Means for solving problems) FIG. 1 is a block diagram of the principle of the present invention.

In the figure, the daisy chain connection system includes one operating section 11 and a plurality of control sections 15. -153 are connected in a daisy chain, and the operating section 11 sends predetermined operation information to the plurality of control sections 15+-153 during monitoring or maintenance.

The validation/invalidity instruction means 13 of the operation unit 11 instructs the plurality of control units 151 to 151 to validate or invalidate the operation.

A plurality of control units 15. ~15. The operation information validity/invalidity determination means 17 determines validity or invalidity indicated by the validity/invalidity instruction means 13, and further validates or invalidates the human input signal when this state continues for a predetermined period.

[Function] The present invention provides a plurality of control units 15. The operation information validity/invalidity determining means 17 of 153 reads the instruction state of the validity/invalidity instruction means 13 of the operation section 11, and when it indicates validity, takes in the input signal as the operation information of the operation section 11. Therefore, when the instruction state in the operating unit 11 indicates invalidity, the signal due to noise is canceled, and malfunctions corresponding to the signal can be avoided.

Furthermore, the operation information validity/invalidity determining means X7 determines whether the operation information is valid/invalid.
Noise in the valid/invalid instruction signal can also be canceled by determining that the invalid instruction signal is true instruction information when the invalid state continues for a predetermined period of time rather than just once.

(Example) Hereinafter, an example of the present invention will be described in detail based on the drawings.

FIG. 2 is a block diagram showing the configuration of an embodiment of the operating section and control section of the present invention.

In the figure, the operation unit 20 includes an operation key switch 21 for performing normal operations, and an activation/activation key switch 21 for operating the operation key switch 21.
A valid/invalid key switch 23 for setting invalidity is connected between the connector 25 and ground.

In the control unit 30, the signal line between the connector 31 and the receiver 33 is pulled up, and the MPU 35, ROM 36, and RAM 37 are connected via the receiver 33 nilocal hash, and the common bus is further connected via the bus controller 39. Further, in this embodiment, a read control signal is sent from the MPU 35 to the receiver 33, and the read control signal is sent to the receiver 33.
The structure is such that the input signal (logical state of the signal line) can be read out accordingly.

Each connector 25 of the operation unit 20 and the plurality of control units 30.
31 are connected via a cable 40 for daisy chain connection.

The characteristic operation of this embodiment will be described below with reference to the flowcharts shown in FIGS. 2 and 3.

The MPU 35 performing normal processing sends a read control signal to the receiver 33 in response to a timer interrupt or other interrupt factor, and first reads the state of the enable/disable key switch 23 of the operation unit 20.

Next, when the same state is detected three times in a predetermined sampling period, it is determined whether it indicates validity or invalidity. If it is valid all three times, the state of the operation key switch 21 is read, the interrupt state is returned, and the corresponding process is executed.

On the other hand, if the state of the enable/disable key switch 23 does not become the same all three times, or if it becomes disabled all three times, the interrupt state is changed to normal without performing the process of reading the state of the operation key switch 21. Return to processing.

Here, the time chart shown in Figure 4 is used to describe the operation in response to the noise that occurs when one of the multiple control units connected in a daisy chain via cables fails and the connector of that control unit is removed. Refer to and explain.

The state of the valid/invalid key switch is latched by the control unit at a predetermined sampling period, and a determination as to whether it is valid or invalid is made.

Note that during normal work, the enable/disable key switch on the operation panel is disabled, and when performing maintenance or other processing after work, it is set to enable and the operation key switch is operated. A predetermined process is executed.

By the way, when a failure occurs in one of the plurality of control units and the connector of that control unit is removed, noise is generated in each corresponding signal line on the control unit side as shown in Fig. 4 as the connector is inserted and removed. . Noise generated on the signal line corresponding to the operation key switch will be ignored if the enable/disable key switch is in the disabled state, but noise may also occur on the signal line corresponding to the enable/disable key switch. is unavoidable.

In this embodiment, as shown in FIG. 3, by latching the state of the valid/invalid key switch at a predetermined sampling period, unless the valid state continues a predetermined number of times (three times in this case) at each sampling point, Malfunctions due to noise on the signal lines corresponding to each key switch are avoided.

〔Effect of the invention〕

As described above, according to the present invention, in a plurality of control units connected in a daisy chain to one operation unit,
The configuration is such that the state of the input signal is taken in as the operation information only when the operation unit instructs the validity of the operation information and this continues for a predetermined period of time.

Therefore, the noise generated when one of the plurality of control units breaks down and the connector of that control unit is removed can be clearly distinguished from the operation information from the operation unit. That is, it is possible to remove the connector while other control units are kept operating without stopping them, and maintenance work efficiency can be significantly improved.

[Brief explanation of drawings]

FIG. 1 is a block diagram of the principle of the present invention; FIG. 2 is a block diagram showing an embodiment of the configuration of the operating section and control section of the present invention; FIG. 3 is a flowchart explaining the characteristic operation of this embodiment; FIG. 4 is a time chart explaining the operation of the embodiment against noise, and FIG. 5 is a block diagram showing the conventional configuration of a daisy chain connection system. In the figure, 11 is an operation unit, 13 is a valid/invalid instruction means, 15 is a control unit, 17 is an operation information valid/invalid judgment unit, 20 is an operation unit, 21 is an operation key switch, 23 is a valid/invalid key switch, 25 is a connector, 30 is a control unit, 31 is a connector, 33 is a receiver, 35 is an MPU, and 36 is a ROM. 37 is a RAM, 39 is a bus controller, 40 is a cable, 51 is an operation section, 53 is an operation key switch, 55 is a control section, and 60 is a cable. Fig. 1 is a block diagram of the principle of the present invention; a flowchart illustrating the configuration of an embodiment of the invention; Fig. 3 is a flowchart explaining the characteristic operation; and Fig. 3: sampling period? ? ? ? Time chart explaining the example operation for “enabled” canceled noise

Claims (1)

[Claims] (1) One operation unit (11) and multiple control units (15_1
~15_3) are connected in a daisy chain, and the operation unit (11) is connected to multiple control units (15_1~) during monitoring or maintenance.
In a maintenance method for a daisy chain connection system that sends predetermined operation information to the operation section (15_3), the operation section (11_3)
) includes a valid/invalid instruction means (13) for instructing the plurality of control units (15_1 to 15_3) to validate or disable the operation;
_3) includes operation information validity/invalidity determination means (13) for determining validity or invalidity indicated by the validity/invalidity instruction means (13), and further validating or invalidating the input signal when this state continues for a predetermined period of time; 17) A maintenance method for a daisy chain connection system.