JPH0332838B2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field] The present invention provides a transmitter that receives a contact output such as a relay contact output or a switch output of a sensor, operates when the contact input changes, and transmits a change detection signal. The present invention relates to a data transmitter equipped with a circuit.

[Background technology] In general, when a contact output such as a relay contact output of a sensor such as a fire detection sensor, a gas detection sensor, or a security sensor, or a switch output such as an emergency switch or a call switch is input, and this contact input changes. In this type of data transmitter equipped with a transmitting circuit that operates to transmit a change detection signal, if the contact output changes again while the change detection signal is being transmitted due to a change in the contact output, the signal changes again. There was a problem in that only the change detection signal indicating the state of the contact output was transmitted, and the first change was ignored. That is,
If the contact output turns off while the contact output is on and a change detection signal is being transmitted, the on change detection signal and the off change detection signal should be sent in succession, but only the off change detection signal is sent. There was a problem that only the files were sent. Therefore, there is a problem that it cannot respond to rapid changes in the contact output (changes that are shorter than the transmission period of the change detection signal).

[Object of the Invention] The present invention has been made in view of the above points, and its purpose is to prevent the contact output from changing again while a change detection signal is being transmitted due to a change in the contact output. It is an object of the present invention to provide a data transmitter that can normally transmit a change detection signal indicating the state of the contact output due to both changes even in such a case, and can cope with rapid changes in the contact output.

[Disclosure of the Invention] (Embodiment 1) Fig. 1 shows an embodiment of the present invention, in which the state of a contact 1 such as a sensor output contact or a switch output is converted into a voltage signal and the input signal V ₁ is converted into a voltage signal. The input circuit 2 to be formed and the input signal V ₁ are connected to the latch clock V ₅
a latch circuit 3 that latches when is input;
A comparator circuit 4 includes an exclusive OR circuit that compares the input signal V ₁ and the output V ₃ of the latch circuit 3 and outputs an input change signal V ₄ when they do not match, and a latch clock that delays the input change signal V ₄ . A delay circuit ₅ consisting of a time constant circuit CR and a Schmitt trigger circuit ST forming an input change signal V ₄ .
The transmission control means 7 includes a monostable multivibrator 6 which is triggered by a monostable multivibrator 6 and sets the operating time of the transmission circuit 8.
A transmission end detection circuit 9a detects the end of transmission of the change detection signal _V8 by differentiating the scan output _S6 and detecting a fall, and a latch clock set by the output of the transmission end detection circuit 9a.
A gate circuit 9c consisting of an R-S flip-flop 9b that is reset at _V5 , and a NAND circuit that inputs the input change signal _V4 to the monostable multivibrator 6 and delay circuit 5 when the R-S flip-flop 9b is set. This is comprised of a retransmission means 9 for operating the comparator circuit 5 again when the transmission of the change detection signal _V8 is completed. Here, the transmission signal forming circuit 8a and the modulation circuit 8b
The transmission circuit 8 is configured such that the power supply is controlled by the monostable multivibrator 6 output V ₆ of the transmission control means 7, and transmits a change detection signal V ₈ based on the latch circuit 3 outputs V ₃ and ₃ when the power is supplied. is formed.

The operation of the first embodiment will be specifically explained below. Now, when the output V ₃ of the latch circuit 3 is “L”, the output contact 1 is turned on and the input signal V ₁ output from the input circuit 2 is “H”.
Then, the input signal V ₁ input to the comparator circuit 4
and the latch circuit 3 output _V3 do not match, and the input change signal _V4 output from the comparator circuit 4 becomes "H".
, and the monostable multivibrator 6 is triggered. On the other hand, in the delay circuit 5, this input change signal
Latch clock V ₅ by delaying V ₄ by a certain amount of time
The latch clock _V5 latches the input signal _V1 to the latch circuit 3, and the output _V3 of the latch circuit 3 is set to "H". By the way, power is supplied to the transmitting circuit 8 for a preset period of time by the output V ₆ of the monostable multivibrator 6, and the transmitting circuit 8 is activated. The pulse width of the power supply control pulse is the change detection signal.
The time required for transmission is set slightly longer than that of _V8 . Here, the transmission signal forming circuit 8a of the transmitting circuit 8
is the output V ₃ of the latch circuit 3 at a predetermined timing,
The modulation circuit 8b forms a transmission signal based on _V3 .
This transmission signal modulates the carrier wave and transmits the change detection signal _V8 . Figure 2 shows the transmission signal forming circuit 8.
This is a time chart showing the operation of step a. After a predetermined reset time To has elapsed from the time the power was turned on, scan outputs S ₁ to _{S 6} are sequentially output at fixed time intervals T ₁ , and among these, S ₁ , The outputs V ₃ and ₃ of the latch circuit 3 are read as scan inputs through transistors Q ₁ and Q ₂ in synchronization with S ₆ . Here, the change detection signal _V8 has a carrier wave (260MHz) at four _different frequencies, as shown in Figure 3.
This is an FSK signal that transmits data by modulating it with a data signal Vd that combines ₄ bits in time series, and in the example, 4 bits are used to prevent interference.
A ₆ -bit code consisting of house codes B2 to _B5 and 2-bit data codes _B1 and _B6 that indicate the type of output contact 1 (fire detection, security, emergency, call, etc.) and contact status (on, off). data is transmitted, and when the change detection signal _V8 is transmitted continuously, a no-signal period corresponding to 2 bits is provided between the signals _V8 .

By the way, in the present invention, the output _V9 of the R-S flip-flop 9b is reset to "L" by the output _V5 of the delay circuit 5, and is determined by the end detection pulse outputted from the transmission end detection circuit 9a. If the input change signal _V1 of the comparator circuit 4 is obtained at the end of transmission, that is, the output contact is set to "H" while the change detection signal _V8 is being transmitted. 1 is turned off, the input change signal _V4 is input to the delay circuit 5 and the monostable multivibrator 6 via the gate circuit 9c, and the comparator circuit 4 is activated again, so that the output contact is output from the transmitting circuit 8. A change detection signal V ₈ is transmitted indicating that V 1 has been turned off. Therefore,
In the present invention, even if the output contact 1 changes again while the change detection signal _V8 is being transmitted due to a change in the output contact 1, the state of the output contact 1 due to both changes is indicated. The change detection signal _V8 can be transmitted normally, and it can sufficiently cope with fast changes in the contact output (changes shorter than the transmission period of the change detection signal _V8 ).

Note that the change detection signal _V8 emitted from the data transmitter is received by a data receiver (not shown),
The data receiver checks whether the house codes B ₂ to _{B 5} match, and if they match, the data code is
Based on _B1 to _B6 , the load corresponding to the output contact 1 is controlled (blinking of an indicator light, generation of an alarm sound by a speaker, etc.).

In addition, in the embodiment, the comparator circuit 5 output V ₄
Although the monostable multivibrator 6 is triggered by the output V5 of the delay circuit 5, the monostable multivibrator 6 may be triggered by the output _V5 of the delay circuit 5. In this case, the monostable multivibrator 6 may be triggered by the output V5 of the delay circuit 5. If there is no input change, the monostable multivibrator 6 will not be triggered, so no unnecessary change detection signal V ₈ will be sent due to noise or chatter of the output contact 1, and malfunctions can be prevented. .

[Effects of the Invention] As described above, the present invention provides a transmitting circuit that receives a contact output such as a relay contact output or a switch output of a sensor, operates when the contact input changes, and transmits a change detection signal. Compare the input circuit that converts contact input into a voltage signal to form an input signal, the latch circuit that latches the input signal when a latch clock is input, and the input signal and latch circuit output in a data transmitter equipped with a comparator circuit that outputs an input change signal when the input change signal does not match; a delay circuit that delays the input change signal to form a latch clock; and a monostable multi-channel circuit that is triggered based on the input change signal and sets the operating time of the transmitter circuit. A transmission end detection circuit which together with the vibrator forms a transmission control means and which detects the end of transmission of the change detection signal; an R-S flip-flop which is set by the output of the transmission end detection circuit and reset by a latch clock; Since the retransmission means is provided with a gate circuit that inputs the input change signal to a monostable multivibrator and a delay circuit when the flip-flop is set, a change detection signal is transmitted due to a change in the contact output. Even if the contact output changes again during the process, a change detection signal indicating the state of the contact output due to both changes can be transmitted normally, and there is an effect that it is possible to cope with rapid changes in the contact output.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of an embodiment of the present invention, and FIGS. 2 and 3 are explanatory diagrams of the same operation. 1 is an output contact, 2 is an input circuit, 3 is a latch circuit, 4 is a comparison circuit, 5 is a delay circuit, 6 is a monostable multivibrator, 7 is a transmission control means, 8 is a transmission circuit, and 9 is a retransmission means. .

Claims (1)

[Claims] 1 In a data transmitter equipped with a transmission circuit that receives a contact output such as a relay contact output or switch output of a sensor and operates when this contact input changes and transmits a change detection signal, the contact input is converted into a voltage signal. An input circuit that converts the input signal into an input signal to form an input signal, a latch circuit that latches the input signal when the latch clock is input, and provides the latch output to the oscillation circuit, and compares the input signal and the output of the latch circuit to determine if there is a discrepancy. A comparator circuit outputs an input change signal when A transmission end detection circuit that forms the transmission control means and detects the end of transmission of the change detection signal, an R-S flip-flop that is set by the output of the transmission end detection circuit and reset by a latch clock, and an R-S flip-flop are set. 1. A data transmitter comprising retransmission means comprising a gate circuit for inputting an input change signal to a monostable multivibrator and a delay circuit when the input change signal is input to a monostable multivibrator and a delay circuit.