JPH10285192A - Common line multiple transmission display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate connection troubles by making the connection of a controller and a terminal non-polar and to miniaturize a transformer shape that is used by the terminal. SOLUTION: A controller 1 has a modulation circuit 8 which modulates a carrier with a sending signal through any of differential PSK modulation, bipolar coding modulation and FSK modulation and a power supply and data transmitting circuit 9 which sends a modulated carrier signal as a voltage signal of high voltage to each terminal. Each terminal 3a to 3d has a step-down transformer 4 which steps down and receives a high voltage modulated carrier signal that is sent from the controller, a demodulation circuit 5 which demodulates the carrier signal that is stepped down and received by the transformer 4 so as to perform display operation on an indicator of the terminal and a diode bridge 6 which rectifies the carrier signal that is stepped down and received by the transformer 4, feeds power to an indicator of each terminal and returns a reply signal through the step-down transformer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a common line multiplex transmission display device, and more particularly, to a common line multiplex transmission system which eliminates connection trouble by making the connection between a controller and a terminal non-polar and reduces the size of a transformer used in the terminal. The present invention relates to a transmission display device.

[0002]

2. Description of the Related Art Hitherto, an exit display device as shown in FIG. 3 has been proposed. In this access display device, the controller 21 is connected to terminals 23a, 23b, and 23c, which are controlled devices, via two common lines L1 and L2. Push button switches 24a, 24b, 24c are connected to the terminals 23a, 23b, 23c, respectively.

In FIG. 4, a controller 21 includes a transmission driver 27, a signal processing unit (CPU) 28, a differential amplifier 29,
It comprises a current detection resistor 30. Each terminal 23a, 23b, 2
3c is a rectifier bridge 31, a return driver 32, a signal processing unit 33, a transistor Tr, and an LED 3 as a display.
4. Consisting of a constant voltage diode 35.

The operation of such an ingress / egress display device will be described. The controller 21 includes a pre-set address data (address 1, address 2,...) Of each of the terminals 23a, 23b, 23c and a terminal. (Controlled machine)
Are sequentially transmitted to two common lines L1 and L2 (FIGS. 5 and 7). In FIG. 4, the address and the display data are transmitted from the signal processing unit 28, and the transmission driver 27 transmits the NRZ (nonreturn-to-zero).
The data is converted into high voltage data of ± 24 V (48 V) in a transmission code format (FIG. 6) and transmitted to two common lines L1 and L2. The transmitted high-voltage data is transmitted to the terminals 23a, 23b, and 23c.
, And rectified by the rectifying bridge 31 to a DC voltage of about 24 V and used as a power supply source for the terminals 23a, 23b, and 23c. 5V with constant voltage
The data of the PP is generated and input to the signal processing unit 33 as a reception signal. After comparing the addresses of the terminals 23a, 23b, and 23c given in advance with the addresses of the received signals, the signal processing unit 33 accepts the next display data only when the addresses match.

In this case, if the addresses match, the signal processing unit 33 turns on / off the LED 34 as a display via the transistor Tr. That is, the signal processing unit 33 turns on the transistor Tr to turn on / off the LED 34.
By turning on / off, the LED 34 is turned on / off by a 24 V DC power supply. The signal processing unit 33 informs the controller 21 that the data has been received without fail.
The return signal is subjected to voltage-current conversion by the return driver 32 and returned to the controller 21 as a current signal through the two common lines L1 and L2. The return signal is current-voltage converted by the current detection resistor 30, amplified by the differential amplifier 29, and sent to the signal processing unit 28 as return signal data. The signal processor 28 completes a series of operations by recognizing the return signal. The signal processing unit 28 repeats these operations.

[0006]

In such a multiplex transmission display device, the address previously assigned to the terminal 23a is "2", and the red LED of the display 34 in the terminal 23a is turned on. Assuming that the control data for driving the transistor Tr is "8", the data format is as shown in FIG.

This data passes through the rectifying bridge 31 and is identified by the signal processing unit 33 as described above, and the transistor Tr is driven to turn on the red LED. However, in this multiplex transmission display device, two common lines L
1. When connecting L2 and the terminal 23a, it was necessary to match the polarities. Because the transmission signal codes (NRZ ± 24v) on the two common lines L1 and L2 are polar, if the connection is reversed, the data is inverted as shown in FIG. The data could not be read accurately by the signal processing unit 33.

If the transmission signal codes (NRZ ± 24v) on the two common lines L1 and L2 often include the same code, low frequency components increase as shown in FIG. When power is supplied, there are difficulties such as an increase in the size of the transformer. SUMMARY OF THE INVENTION The present invention has been made to solve such difficulties, and has a common line multiplex transmission display which eliminates connection troubles by making the connection between the controller and the terminal non-polar, and reduces the size of the transformer used in the terminal. It is intended to provide a device.

[0009]

In order to achieve this object, a common line multiplex transmission display device of the present invention connects a controller and a plurality of terminals having a display with two common lines,
The controller sequentially and cyclically sends a transmission signal of the address data to the terminal device via the common line, and subsequently the display data for performing the display operation on the display device of the terminal device. When the address data transmitted via the line coincides with its own preset address data, a display operation is performed on the display of the terminal device, and the address data is transmitted to the controller, and then transmitted. It sends out a reply signal with confirmation data confirming the reception of the received display data.

The controller comprises a modulation circuit for modulating a carrier with a transmission signal by any one of differential PSK modulation, bipolar code modulation, and FSK modulation, and each terminal converts the modulated carrier signal to a high voltage signal. And a power supply / data transmission circuit for transmitting the data to the computer. Each terminal unit steps down the high-voltage modulated carrier signal sent from the controller and receives it, and demodulates the received carrier signal after stepping down with the step-down transformer and displays it on the display unit of the terminal unit A demodulation circuit for performing the operation and a diode bridge for rectifying the received carrier wave signal by stepping down a step-down transformer, supplying power to the display of each terminal device, and transmitting a return signal via the step-down transformer.

[0011] In this common line multiplex transmission display apparatus, the transmission signal of the address data from the controller to the terminal via the common line and the display data which subsequently performs the display operation on the display of the terminal. Are sequentially transmitted cyclically. The terminal device performs a display operation on the display device of the terminal device when the address data transmitted via the common line matches the preset own address data, and the terminal device has its own address data, Subsequently, a reply signal is transmitted with confirmation data confirming reception of the transmitted display data. In this case, the controller uses a differential circuit to perform differential PSK modulation, bipolar code modulation,
A carrier is modulated with a transmission signal by any one of the FSK modulations, and the modulated carrier signal is transmitted to each terminal as a high voltage signal by a power supply / data transmission circuit.

[0012] Each terminal unit receives the down-converted high-voltage modulated carrier signal sent from the controller in the step-down transformer, and the demodulation circuit demodulates the received carrier signal down-converted by the step-down transformer. In addition to performing the display operation on the display of the device, the received carrier signal is stepped down by the step-down transformer, rectified by the diode bridge, supplied to the display of each terminal device, and the return signal is transmitted through the step-down transformer.
In this manner, the common line multiplex transmission display device of the present invention can eliminate the connection trouble by making the connection between the controller and the terminal non-polar, and reduce the size of the transformer used in the terminal.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a common line multiplex transmission display device of the present invention will be described in detail with reference to the drawings showing a preferred embodiment thereof. As shown in FIG. 1, the common line multiplex transmission display device of the present invention comprises a controller 1 and a plurality of terminals 3a, 3b, 3c, 3d as controlled devices each having a two-color LED display 2.
Are connected by two common lines L1 and L2.

The controller 1 sends address data d11, d21,... To the terminals 3a, 3b, 3c, 3d via two common lines L1, L2, and subsequently the terminals 3a, 3b,. 3
A transmission signal D comprising display data (color data) d12, d22,... for performing a display operation on the two-color LED display 2 of c, 3d.
1, D2... Are sequentially transmitted cyclically (FIG. 7).

Since the terminals 3a, 3b, 3c, and 3d have the same circuit configuration, only the terminal 3a will be described in detail below. The terminal device 3a receives the address data d1 transmitted through the common lines L1 and L2.
When the terminal device 3a matches 1, d21,... With its own address data d1 preset in the address memory 10b.
The display operation is performed by the two-color LED display 2, and the control unit 1 confirms reception of its own address data d11 and subsequently received display data (color data) d13. And a function of sending a reply signal D11.

The controller 1 is composed of a central processing unit 10 and address data d11, d21,... Controlled by the central processing unit 10 and display data (color data) d12, d22,. The transmission signals D1, D2,.
A differential PSK (Phase Shift Keying) modulation circuit 8 for modulating a carrier with a power / data transmission circuit 9 for transmitting the modulated carrier signal to each of the terminals 3a, 3b, 3c and 3d as a high voltage signal. have.

The differential PSK modulation circuit 8 compares the phase of the previous bit with that of the current bit and determines whether it is 0 or 1 depending on whether the phases are equal or different. Need not be given a reference phase. The power supply / data transmission circuit 9 includes transistors Tr1 and Tr2; Tr3 and Tr4, respectively.
The carrier signal modulated by the K modulation circuit 8 is supplied to a power supply 24.
v, that is, the differential PSK ± 24v is added to the two common lines L
1 and a pair of balance transformerless (BTL) drivers for inverting and transmitting the signals to L2, so that the CPU (signal processing unit) 10 has an inverter connected to the bases of the transistors Tr1 and Tr2 via the differential PSK modulation circuit 8. They are connected to the bases of the transistors Tr3 and Tr4 via INV, respectively.

Each terminal 3a, 3b, 3c, 3d is connected to the controller 1
Step-down transformer 4 that steps down and receives the high-voltage modulated carrier signal sent from the oscilloscope and sends out a return signal D11.
And demodulates the carrier signal received by stepping down the step-down transformer 4 to obtain a two-color LED display 2 of each of the terminals 3a, 3b, 3c and 3d.
A demodulation circuit 5 for performing a display operation on each terminal 3
a, 3b, 3c, 3d, a current sending circuit 7 for transmitting a return signal D11 from the controller 1 as a current signal to the controller 1, and a signal power extracted from the high-voltage carrier signal sent from the controller 1 to rectify the signal power. Diode bridge 6 to supply to circuit part
And an operation switch SW for performing a display operation in the two-color LED display 2 of each of the terminals 3a, 3b, and 3c and the controller 1.
1. It has a central processing unit 10a for performing these controls.

The operation switch SW1 is connected to the diode bridge 6 in series with the resistor R1, and its opening / closing signal is input to the central processing unit 10a. Each terminal 3a, 3b, 3c, 3d
The two-color LED display 2 comprises a red LEDLD1 and a blue LEDLD2, and is controlled by the controller 1 in accordance with display contents, and is turned on / off. The central processing unit 10a includes a transistor Q1,
It has a function of driving the red LEDLD1 and the blue LEDLD2 via Q2.

Further, the control unit 1 includes the terminals 3a, 3b, 3
c, a resistor 12a for current-voltage conversion of a current signal as a return signal D11 sent from 3d, and a differential amplifier 1
2b, and a low-pass filter (LPF) 11 that removes high-frequency components such as noise from the output from the current-voltage conversion circuit 12 and inputs the same to the central processing unit 10 as a reception signal D11.

In the thus constructed common line multiplex transmission display device, the controller 1 controls the address data d11, d21, d11, d21, , Followed by display signals d12, d22,... For performing display operation on the display 2 of each of the terminals 3a, 3b, 3c, 3d. And a carrier signal modulated from the transistors Tr1, Tr2; Tr3, Tr4 of the power supply / data transmission circuit 9 as a high voltage signal of differential PSK ± 24V (48V). Line L
1, and sequentially transmitted to L2.

When the transmitted high-voltage signal reaches each terminal 3a, 3b, 3c, 3d, for example, the terminal 3a, it is received via the step-down transformer 4, rectified by the diode bridge 6, and rectified by about 5 V DC. The voltage is converted to a power supply for the terminal 3a. On the other hand, the voltage signal received via the step-down transformer 4 is demodulated by the demodulation circuit 5 into address data and display data. The demodulated address data is input to the central processing unit 10a, and the terminal device 3a assigned in advance
After comparing with the address data d1 set in advance in the address memory 10b, the next display data is accepted only when they match. In this case, if the addresses match, the LED display 2 of the terminal 3a is displayed according to the display data.
Is turned on / off to perform the display operation. For example, when it is desired to display “out” and “occupied” on the terminal 3a, respectively, the carrier is transmitted from the controller 1 to the terminal 3a by the differential PSK as described above, and the central processing unit 10a transmits the transistors Q1, Red LEDLD1, Blue LE via Q2
DLD2 is driven and turned on / off.

In this case, the address memory 1 of the terminal 3a
Assuming that the address previously assigned to 0b is “2” and the control data for driving the transistor Q1 to turn on the red LED LD1 of the display 2 in the terminal 3a is “8”.
The data format of the differential PSK is as shown in FIG. That is, of the two common lines L1 and L2, a transmission signal of the address of the terminal 3a and the transmission signal of the display data for performing the display operation on the display 2 of the terminal 3a are transmitted to the common line L1. An inverted transmission signal of the address of the terminal 3a and the display data for performing the display operation on the display 2 of the terminal 3a is transmitted to the line L2. Therefore,
By transmitting data in such a data format on the two common lines L1 and L2, the data structure on the two common lines L1 and L2 depends on the relative phase with the previous bit. It is not necessary to determine the polarity in the connection with.

Further, the central processing unit 10a, in order to inform the controller 1 that the data has been received without fail, its own address data d11 and, subsequently, confirmation data which confirms the reception of the transmitted display data. (Color data) d13
Is returned to the controller 1 via the step-down transformer 4 by the current sending circuit 7 as a current signal via 1 and L2.

In the controller 1, the current-voltage conversion circuit 1
The current signal as the return signal D11 sent from each terminal 3a, 3b, 3c is current-voltage converted by the second resistor 12a and amplified by the differential amplifier 12b. The return signal D11 subjected to the current-voltage conversion is input to the central processing unit 10 from the low-pass filter (LPF) 11 as a reception signal D11.
The central processing unit 10 completes a series of operations by recognizing the received signal. The central processing unit 10 repeats these operations.

If the operation switch SW1 is pressed on the terminal 3a when the address data d11 sent from the controller 1 and its own address data d1 match, the central processing unit 10a sends this to the controller. 1 to send a return signal D11 of its own address data d11 and, subsequently, display data (color data) d13, as a current signal by the current sending circuit 7, and from the diode bridge 6 and the step-down transformer 4 Line common line L1,
Reply to controller 1 via L2. In the controller 1, the current signal as the return signal D11 sent from the terminal 3a is current-voltage converted by the resistor 12a of the current-voltage conversion circuit 12, and is amplified by the differential amplifier 12b. The current-voltage converted return signal D11 is a low-pass filter (LP
F) 11 is input to the central processing unit 10 as a reception signal D11. The central processing unit 10 recognizes the received signal,
Perform display processing.

As described above, in the common line multiplex transmission display apparatus of the present invention, the connection between the controller and the terminal can be made non-polar to eliminate the connection trouble. In addition, when power is supplied to a terminal by a transformer even if the transmission signal on the two common lines L1 and L2 contains the same code and contains many low-frequency components, the size of the transformer used in the terminal must be reduced. Can be.

Although the above embodiment has been described only with respect to the terminal 3a, the same applies to the other terminals 3b and 3c, and a description thereof will be omitted. Also, in the above embodiment, the differential P
Although SK (Phase Shift Keying) modulation is used, it may be configured by bipolar (Alternative Mark Inversion) code modulation or FSK (Frequency Shift Keying) modulation.

[0029]

As is apparent from the above description, according to the common line multiplex transmission display apparatus of the present invention, the connection between the controller and the terminal is made non-polar to eliminate the connection trouble and the transformer used in the terminal. The size can be reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram of one embodiment of a common line multiplex transmission display device of the present invention.

FIG. 2 is an explanatory diagram of an operation by the common line multiplex transmission display device of the present invention.

FIG. 3 is a block diagram of a conventional exit display device.

FIG. 4 is a partially detailed circuit diagram of a conventional exit display device.

FIG. 5 is a data organization diagram used in a conventional entry / exit display device.

FIG. 6 is a data configuration diagram used in a conventional exit display device.

FIG. 7 is an explanatory diagram of transmission of data used for a conventional exit display device.

FIG. 8 is an operation explanatory view of a conventional exit display device.

FIG. 9 is an explanatory diagram of an operation in a conventional exit display device.

[Explanation of symbols]

 1 ... Controller 8 ... Modulation circuit 9 ... Power supply / data transmission circuit 12 ... Current-voltage conversion circuit 2 ... Display Units 3a, 3b, 3c, 3d: Multiple terminal units 4: Step-down transformer 5: Demodulation circuit 6: Diode bridge 7: ..Current sending circuit L1, L2... Two common lines d11, d21... Address data d12, d22... Display data d13. Confirmation data d1 ..... self-address data set in advance D1, D2 ..... transmission signal D11 ..... reply signal

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI G08B 25/04 G08B 25/04 F

Claims (2)

[Claims] 1. A control unit (1) and a plurality of terminals (3a, 3b, 3c) having a display (2) are connected to two common lines (L1,
L2), and the controller sends the address data (d11, d21,...) To the terminal via the common line.
, And subsequently, a transmission signal (D1, D2,...) Of display data (d12, d22,...) For performing a display operation on the display of the terminal is sequentially and cyclically transmitted. When the address data transmitted via the common line matches the preset own address data (d1), a display operation is performed on the display of the terminal, and the address is transmitted to the controller. Data (d1
A reply signal (D1) of (1) followed by confirmation data (d13) confirming reception of the transmitted display data.
1) In the common line multiplex transmission display device for transmitting 1), the controller includes a differential P for modulating a carrier with the transmission signal
Any one of SK modulation, bipolar code modulation, and FSK modulation
And a power supply / data transmission circuit (9) for transmitting the modulated carrier signal to each terminal as a high-voltage signal, and each terminal transmits from the controller. A step-down transformer (4) for stepping down the received high-voltage modulated carrier signal and receiving the same, demodulating the received carrier signal stepped down by the step-down transformer and performing a display operation on the display of the terminal device; A demodulation circuit (5) for performing the operation, and a diode for rectifying the received carrier signal after being stepped down by the step-down transformer, supplying power to the display of each terminal device, and transmitting the return signal via the step-down transformer. A common line multiplex transmission display device comprising a bridge (6). 2. Each terminal has a current transmission circuit (7) for transmitting the reply signal from each terminal to the controller as a current signal, wherein the controller is transmitted from each terminal. The common line multiplex transmission display device according to claim 1, further comprising a current-voltage conversion circuit (12) for performing current-voltage conversion of the current signal as the return signal.