JPS59231455A - AC signal presence/absence determination device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical field to which the invention pertains] The present invention relates to an alternating current signal presence/absence determination device that determines the presence or absence of an input signal based on the presence or absence of an alternating current signal.

[Prior art and its problems]

The conventional device was configured as shown in the circuit diagram of FIG. 1 in order to perform control according to the input signal inputted with or without an alternating current signal.

In FIG. 1, 1.2 is an input terminal for input signals, and a signal is input depending on whether or not an AC signal is applied between the terminals 1.2. 3,6. '7,9゜ 0 is a resistor, 4 is a diode, 5 is a capacitor, 8 is a photocoupler composed of a light emitting diode and a phototransistor, 11 is a transistor, 12 is various depending on the signal input to the input terminal 11 This is a chip CPU that performs control.

In a device with such a configuration, a sixth terminal is connected between input terminals 1 and 2.
When a signal is input as shown in figure (A), C! A signal having a waveform as shown in FIG. 6(B) is input to the input terminal 1 of the PU 12. That is, the AC signal input between the input terminals] and 2 is connected to the diode 4. Capacitor 5. It is converted into a DC signal by a signal conversion circuit such as a resistor 6 and a photocoupler 8, and then sent to the CPU 12.
is inputting to. The CPU 12 performs various controls in accordance with the signal converted into a DC signal.

In addition, when performing control according to human input signals, it is also possible to select whether to activate the active state when an AC signal is input or to activate the active state when the AC signal is no longer input. Then, in the standby state, no AC signal is input, but an AC signal is input to perform a certain operation (control), and in the standby state, an AC signal is input, and a certain operation is performed. There may be cases where it is necessary to switch (hereinafter referred to as switching the polarity of the input signal) so that the AC signal disappears when performing the input signal.

For example, the sales start signal, which is the input signal for a coin mechanism used in a vending machine, is input while the product is being carried out, but the sales start signal for a single-price coin mechanism is input as an AC signal in the standby state. The sales start signal of the coin mechanism with double price or higher is that no AC signal is input in the standby state, but an AC signal is input while the product is being transported. It is. The coin mechanism performs operations such as dispensing change when a sales start signal is input. In this case, in order to use the same CPU 12 for the single price and for the double price or more, the transistor 11 is removed and connected as shown by the dotted line in the case of the double price or more. At this time, a signal as shown in FIG. 6(C) is input to the input terminal (1) of the CPU 12.

By doing this, the CPU 12 simply determines that it is active when the signal input to the input terminal ■1 becomes °゛L, and the same C!
PU 12 can be used.

In the device shown in Figure 1, the input AC signal is a commercial A
The specific values of the parts used for ClooV 50/60 Hz JA are as follows: Resistor 3 is 100Ω8W,
Diode 4: 100OV (High voltage is required for surge resistance) A1 Capacitor 5: 2.2μF 35
0"i'/V, resistor 6 is Ω armored to J5, resistor 7 is 820Ω
'/4W.

In the conventional device as described above, since AC signals are converted to DC signals, high voltage diodes 4. High-voltage capacitors 5 and the like are required, which poses problems in terms of cost, space, and reliability.Transistor 11 is used to switch the polarity of human input signals, making it impossible to use a common signal conversion circuit. Therefore, there is a problem particularly when switching the polarity of an input signal using the same printed circuit board.

[Purpose of the invention]

In view of the above-mentioned points, the present invention provides an input signal conversion circuit with 1π
) It is an object of the present invention to provide an alternating current signal determination device that can easily switch the polarity of an input signal.

[Key points of the invention]

FIG. 2 is a block diagram showing the configuration of the present invention. and a timer whose timekeeping contents are cleared each time a pulse of the pulse signal is input; By including a determining means that determines that the AC signal is not input when a predetermined time longer than the cycle of the AC signal is measured, the input signal conversion circuit is simplified, and furthermore, it is possible to simplify the input signal conversion circuit and further determine whether or not the input signal is an AC signal. a switching means for switching which case is to be set as an active state, and a control means for performing control according to a determination result of the determining means based on the switching means, the clocking means, the determining means, and the control. By configuring the means and means with a single-chip CPU, the polarity of the input signal can be easily switched.

[Embodiments of the invention]

The present invention will be described in detail below with reference to the drawings.

FIG. 3 is a circuit diagram of an embodiment of the present invention. In FIG. 3, 1.2 are input terminals for input signals similar to those in FIG. 1, ], 3, 14. , 18 is a resistor, 15 is a diode, code 6 is a photocoupler, 17 is a 1-chip CPU %
1'20 is RAM in 0PTJ l'7, 19,
20 is the diode, ■++I2+T5 is the CPU] f7
The input terminal of 01 is the output terminal of CPU 1'7.

Here, the diode 9 is for switching the polarity of the input signal input to the terminal 1, and is installed when the input signal is an AC signal and is active, and when the input signal is no AC signal, it is installed. Do not install it if it is active.

Diode 20 is for switching other conditions. These conditions are such that a strobe signal is output from the output terminal 01 and read at the input terminal I2 and the input terminal 5.
Although not shown, other signals (
conditions, etc.) are also input using other strobe signals, so
Diodes are used for 19 and 20 to prevent signal recirculation.

In a device with such a configuration, when a signal as shown in Figure 7 (A) is input between terminals 1 and 2, the CPU outputs a signal as shown in Figure 7 (B) to input terminal 1. A signal is generated. That is, the AC signal input between terminals 1 and 2 is passed through resistor unit 3. Diode 15. The signal is half-wave rectified by a signal conversion circuit including a photocoupler 16 and the like, converted into a Noculus signal, and inputted to the input terminal 1 of the CPU 1'7.

To show the specific values of the parts used in this signal conversion circuit, if the input AC signal is commercial AC], OOV, the resistor 13 is 15KflIW, the resistor 14 is 52ON, and the diode is 30V 100mA. Compared to the conventional device shown in FIG. 1, the ratings of the parts used can be smaller, the number of parts can be reduced, and the signal conversion circuit can be simplified.

However, in the present invention, since the input AC signal is not converted into a DC signal but into a pulse signal, it is necessary to determine whether or not an AC signal is input based on this pulse signal. Therefore, in the embodiment of the present invention, the operating program is as shown in FIG.

It is configured as shown in the flowchart of FIG.

FIG. 4 shows a configuration that starts at terminal 100 and ends at terminal 110, and this operation program is repeatedly executed every predetermined period of time (for example, 2m8) using a timer interrupt. It's Nishide.

In FIG. 4, first, in step 101, it is determined whether a pulse ('R pulse) is input to terminal 1 (whether terminal 1 is at L level or not), and if a pulse is input, AC If it is determined that there is a signal, the process proceeds to step 1.02, and if it is not input, the process proceeds to step 104.In step 02, the signal memory in RAM 1'7'O]71(
3) and proceeds to step 103. In step 103, the word 4 o'clock memory 1' in R, AM 1'70 is set.
72 (FIG. 3) and proceeds to step 10'7.

In step 104, the contents of the erasing memory 172 are glassed by [in step 106, which will be described later], to a predetermined value greater than or equal to the period of the input AC signal (for example, if the input AC signal is
In the case of Hz, the period is 20 m8, so if the program in Figure 4 is executed every 2 ms, this predetermined value is 10 (=
20m5÷2ms) or more. Further, this predetermined value may be determined by considering the possibility of instantaneous interruption of the input AC signal and the responsiveness to the input signal, but it is appropriate to set it to about two periods of the AC signal. ) is reached, and if so, it is determined that there is no AC signal and the process proceeds to step 105; if not, the process proceeds to step 106. In step 105, the signal memory 1'71 is reset, and in step 106, the clock memory 1'72 is reset by +1.
Then, proceed to step 10'7.

That is, the clock memory 1'72 is incremented by 1 every predetermined period (for example, 2 ms) when steps], 06 are executed. In step 10'7, a strobe signal is output from terminal 01, the state of terminal 2 is read, it is determined whether it is switched to be active when an AC signal is present, and whether it is switched to be active when an AC signal is present or not is determined. If so, the process proceeds to step 109, and if the AC signal is active without an AC signal, the process proceeds to step 108. In step 109, the contents of the signal memory 1'71 are transferred to the RAM 1'.
In step 10, the inverted contents of the signal memo 1J171 are stored in the control memory 173 and colored at the terminal 110.

When the above operation is performed, the signal memory 171 is set when the AC signal is input, and the signal memory 171 is set when the AC signal is input.
Since the signal is reset when no signal is input (for a predetermined period of time or more), the signal presence memo IJ 17] can be referred to to determine whether or not an AC signal is input. - Every once control memory unit 73 is set when the input signal is in an active state, and reset when it is not in an active state, so control according to the input signal refers to this control memory 173. For example, as shown in FIG. 5, this may be done regardless of the polarity of the human input signal. That is, in FIG. 5, it is determined in step 201 whether or not the control memory 173 is set, and if it is not set, control l is executed in step 202 and the process returns to step 2 (this state is a standby state). If set, it is assumed that a signal indicating active has been input, and control 2 is executed in step 203. For example, in a coin mechanism used in a vending machine, when the input signal is a sales start signal, control 1 is an operation to determine whether the sale is possible by comparing the input amount and the selling price, and control 2 is an operation to dispense change. etc.

〔Effect of the invention〕

According to the present invention as described above, since the input signal that is input based on the presence or absence of an AC signal is converted into a pulse signal without converting it into a DC signal and the presence or absence of an AC signal input is determined, the signal conversion The circuit can be simplified, and furthermore,
Since a means for switching the polarity of the input signal is provided and control is performed according to the input signal based on this switching means, the polarity of the human input signal can be easily switched.

[Brief explanation of drawings]

Fig. 1 is a circuit diagram of a conventional device, Fig. 2 is a block diagram showing the configuration of the present invention, Fig. 3 is a circuit diagram of an embodiment of the present invention, and Figs. 4 and 5 are operation of the screen embodiment. Flowchart showing the program, Figure 6 is a waveform diagram of the conventional device, Figure 7 is Example 2
0 waveform diagram. 1.2... Input terminal for input signal, 3,6. '/, 9,
10゜13, 14, 18...Resistance, 4,]-5,
19, 20...Diode, 5...Capacitor, 8
．． ]-6...Photocoupler, 11...Transistor,
Ko2,. 17...1 chip CPU. = 3shi 17th layer Figure 3 Noah /7gu Atsushi 2 figure L J Me Otsu figure 7

Claims (1)

[Scope of Claims] 1) Signal converting means for half-wave rectifying an input signal inputted with or without an alternating current signal and converting it into a pulse signal; a timekeeping means whose timekeeping contents are cleared when a pulse of the pulse signal is input, and when it is determined that the alternating current signal is input, and the timekeeping means measures a predetermined time longer than the period of the alternating current signal; An alternating current signal presence/absence determining device, comprising determining means for determining that the alternating current signal is not input. 2) Signal converting means for half-wave rectifying an input signal inputted with or without an alternating current signal and converting it into a pulse signal; and a signal converting means that measures time at a predetermined period and clears the time measurement contents each time a pulse of the pulse signal is input. and a clocking means that determines that the alternating current signal is input when a pulse of the pulse signal is input, and that the alternating current signal is not input when the clocking means measures a predetermined time longer than the period of the alternating current signal. a determining means for determining whether the input signal is an AC signal, a switching means for switching whether the input signal is in an active state, and control according to the determination result of the determining means based on the switching means. 1. An alternating current signal presence/absence determination device, comprising: a control means, and wherein the time measurement means, the determination means, and the control means are configured by a single-chip CPU.