JPS6242216A - Power supply controller - Google Patents

Abstract

PURPOSE:To attain the automatic make/break of a power supply without using an exclusive circuit nor a control program, by closing a switching circuit only for a prescribed period of time after the signal on a transmission line is detected and securing the automatic application of the power supply. CONSTITUTION:A master device 11 delivers continuously the polling signals (a) onto a transmission line 2 at a fixed time interval when the transmission of the sales data is requested to each slave device 14. The signal (a) is supplied to a power supply controller 17 via a branching device 13 and a signal extracting line 18. A signal detecting circuit 20 of the controller 17 delivers the pulse signals (c) of the prescribed short width synchronously with the input time points t0, t1... of the signals (a). A monostable circuit 21 receives the first signal (c) and has a rise to an H level from an L level at the time point t0 and is kept at the H level just for a prescribed period of time. A switching circuit 23 is closed when a control terminal is set at an H level at the point t0. Then an AC power supply (e) is supplied to each device 14 via a power supply line 22.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a power control O8 device for controlling power on/off of each information processing device in a system in which a plurality of information processing devices are connected via a transmission path.

“Conventional technology” For example, P
In the O3 (point of sale) system, as shown in Figure 4, one main device 1 consists of a file control section, etc.
A plurality of slave devices 4, which are electronic cash registers, are connected to each other via transmission lines 2 and branching devices 3. In such a system, program data is transmitted from the main device 1 to each slave device 4 via the transmission line 2 and branch device 3, and sales data registered in each slave device 4 is collected to the main device 1. In this case, there is a device configured so that the power to each slave device 4 can be automatically turned on or cut off based on a command from the main device 1. That is, as shown in FIG. 4, a power supply control device 5 is provided to control the power on/off of each slave device 4, and the power is transmitted from the main organ 1 to this power supply control device 5 via a dedicated signal line 6. By sending a power-on signal and a power-off signal, the main device 1 remotely controls the power-on/off of each slave device 4.

[Problems to be Solved by the Invention] However, the power supply control device [5] configured as described above still has the following problems.

That is, since a dedicated signal line 6 is required to connect the main device 1 and the II source control device 5, wiring work for the dedicated signal line 6 is required, and material costs increase, so the overall system There was a problem of rising manufacturing costs.

Also, on the main device 1 side, a separate control program is required to send a power-on signal and a power-off signal to the power supply control device 5. As a result, there is a problem that the program configuration of the entire system becomes complicated.

The present invention has been made based on the above circumstances, and its purpose is to detect a signal transmitted on a transmission path that connects devices and turn on the power of the device receiving the signal. To provide a power supply control device that can automatically turn on/off the power of a receiving device without using a dedicated signal line or a power on/off control program by automatically turning on the power. be.

[Means for Solving the Problems] The lft m 1ll Ill device of the present invention uses a signal detection circuit to detect a signal transmitted on a transmission line connecting a plurality of information processing devices, and uses a timer circuit to detect a signal transmitted on a transmission line connecting a plurality of information processing devices. The timer circuit measures a predetermined specified time from the time when the signal is detected, and is connected between the information processing device on the side receiving the signal and the external power source. 1 A switching circuit is provided which is closed during the time period.

[Operation] With the power supply control device configured as described above, when a signal is transmitted on a transmission path connecting information processing devices, this signal is detected by the signal detection circuit. When the signal is detected, the switching circuit is closed for a predetermined period of time from the detection time, and the power of the information processing equipment on the side that receives the signal is automatically turned on for the specified period of time.

[Example] An embodiment of the present invention will be described below with reference to the drawings.

FIG. 2 is a block diagram showing the entire system incorporating the power supply control device of the embodiment, and numeral 11 in the figure is a main device as an information processing device that first sends out a signal. This main device 11 is connected via a transmission path 12 and a branching device 13 to a plurality of slave devices 14 serving as information processing devices on the signal receiving side. The main device 11 is supplied with power directly from an AC power source (not shown) via a plug 15, and each slave device 14 is supplied with power from an AC power source (not shown) via a plug 16 and a power control jII device 17 according to an embodiment of the present invention. Supplied via Note that this 'ImilJa device 17 is connected to a branching device via a signal take-out line 18. 13.

FIG. 1 is a block diagram showing a schematic configuration of the power supply control device 17. As shown in FIG. That is, in the branching device 13, the signal output line 18 taken out via the signal detection transformer 19 at a position on the input transmission path 12 before being branched to each slave device 14 is guided into the power supply control device 17. and is connected to the input terminal of the signal detection circuit 20. When the signal detection circuit 20 receives a signal from the signal output line 18,
H normalized to TTL level in synchronization with signal input time
Outputs a level pulse signal. This signal detection circuit 20
The output terminal of is connected to the trigger input terminal of a monostable circuit 21 as a timer circuit.

This monostable circuit 21 is composed of, for example, a retrigger type one-shot multivibrator. An output signal that remains at H level for a specified time To determined by a constant is output. The output terminal of this monostable circuit 21 is connected to a control 11 terminal of a switching circuit 23 inserted between the AC power supply and the 'R source supply line 22 connected to the power supply terminal of each slave device 14. This switching circuit 23 is composed of a power control circuit using, for example, a thyristor, and when an H level signal is input to the control terminal, this switching circuit 23 is closed, and the switching circuit 23. Power is supplied to each slave device 14 via the II power supply Ji 122.

The operation of the power supply control device [17] configured as described above will be explained using the time chart shown in FIG.

That is, in general, when the main device 11 requests each slave device 14 to transmit, for example, sales data, it continues to output a polling signal a indicating a transmission procedure onto the transmission line 2 at regular time intervals Tp. This polling signal a is then input to the branching device 13.

Then, this polling signal a is continuously transmitted on the transmission line 12 and is inputted to the power supply control device 17 via the signal detection transformer 19 and the signal output line 18. The polling signal a input to the power supply control device 17 is input to the signal detection circuit 20. The signal detection circuit 20 that received the polling signal a detects the input time t of the polling signal a,
, t2.

In synchronization with t3..., an H level pulse signal C having an extremely short predetermined width is output. Then time 1. The monostable circuit 21 receives the first pulse signal C at the pulse input time 1. The signal rises from the L level to the H level and remains at the H level for a specified time To. Outputs an output signal d.

Then, time 1. The control terminal of the switching circuit 23 becomes H level, the switching circuit 23 is opened, and the AC power supply e is supplied to each slave device 14 via the power supply line 22.
supplied to As a result, each slave device 14 is powered on at time tO, and each slave device 14 shifts to an operating state.

Note that the value of the specified time To in the monostable circuit 21 is set to a value larger than the value of the time interval Tp of the polling signal a sent from the main device 11 to the transmission line 12 by adjusting the above-mentioned time constant. Therefore, one pulse signal C is input from the signal detection circuit 20 and the next pulse signal C is input before the prescribed time To has elapsed, so as long as the polling signal a is continuously output, The output signal d of this monostable circuit 20 never changes to L level.

Therefore, the power to each slave device 14 will not be interrupted midway.

On the other hand, the polling signal a input to the branching device 13 is branched by the branching device 13 and input to each slave device 14.

Each follower 14 that has received the polling signal a sends out a data signal containing sales data, etc. to the transmission line 12 in the order (timing) specified by the polling signal a. Main equipment 1
1 takes in data signals sent from each slave device 14 to the transmission line 12.

Then, when the main device 11 stops sending out the polling signal a to the transmission path 12 when it finishes receiving a series of data signals, at time t4 when a specified time To has elapsed from the sending time t3 of the last polling signal a. Then, the output signal d of the monostable circuit 21 changes from H level to L level. When the output signal d changes to the L level, the switching circuit 23 is opened, and the supply of the 'R source to each slave device 14 is cut off. Thus, each slave device 14 transitions to a power-off state at time t4.

With the power control device 17 configured in this way, when the polling signal a is sent from the main device 11 to the transmission line 12, the power to each slave device 14 is automatically turned on and the sending of the polling signal a is stopped. Then, after a predetermined period of time To has elapsed, the power to each slave device 14 is automatically cut off. Therefore, there is no need for the main device 11 to perform a special operation for turning on the power to each slave device 14.

In addition, since the main device 11 does not need to send a power-on signal or a power-off signal to the transmission line 12 or the power control device 17 in order to automatically turn on the power to each slave device 14, There is no need to provide a control program.

As a result, the program configuration of the entire system is simplified. It also saves the cost of developing programs.

Furthermore, since there is no need to provide a dedicated signal line for connecting the main device 11 and the power supply control device 17, the manufacturing cost of the entire system can be reduced.

Note that the present invention is not limited to the embodiments described above. In the embodiment, a plurality of slave devices 14 are provided, but one
It may be a stand. Further, in the embodiment, the timer circuit is configured by the monostable circuit 21, but it can also be configured by a counter circuit for counting clock signals.

[Effects of the Invention] As explained above, according to the present invention, a signal transmitted on a transmission path connecting information processing devices is detected and the power of the information processing enclosure on the side receiving the signal is automatically turned on. I am trying to invest in it. Therefore, the power to the receiving device can be automatically turned on and off without using a signal line dedicated to power on and off, and without using a power on and off control program.
The entire system incorporating this power supply control device can be simplified and manufacturing costs can be reduced.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing a schematic configuration of a power supply control device according to an embodiment of the present invention, Fig. 2 is a block diagram showing the entire system incorporating the embodiment, and Fig. 3 is an operation of the embodiment. Figure 4 is a time chart showing the conventional power supply II t.
FIG. 1 is a block diagram showing the entire system incorporating the I device. 11...Main equipment (information processing equipment), 12...Transmission line, 13...Branch device, 14...Subconcentrator (information processing equipment), 15.16...Plug, 17... - Power supply control device, 18... Signal take-out line, 20... Signal detection circuit,
21... Monostable circuit (timer circuit), 23... Switching circuit. Applicant's agent Patent attorney Takehiko Suzue b Figure 1 Figure 2

Claims (1)

[Claims] A signal detection circuit that detects a signal being transmitted on a transmission path connecting a plurality of information processing devices, and a timer that measures a predetermined time from the time when the signal detection circuit detects the signal on the transmission path. and a switching circuit that is inserted between the information processing device on the side that receives the signal and an external power source, and that is closed while the timer circuit is counting the specified time. power control device.