JPH0457421A - Analog terminal equipment - Google Patents

Abstract

PURPOSE:To allow one and same analog terminal equipment to cope with various applications in which number of analog sensor elements and kinds are different from each other by providing a setting circuit to set a transmission format for data transmission. CONSTITUTION:When a transmission format is set by an optical wireless transmitter 44 for an object of sensor elements 1a, 1b, an optical wireless signal is received by a photodetector 43 and an optical wireless reception circuit 42 writes the transmission format of a transmission data to an E<2>PROM 41 based on the sent optical wireless signal. A multiplex transmission circuit 3 receives both analog data of the sensor elements 1a, 1b and sends the analog data of the sensor elements 1a, 1b according to the format set in the E<2>PROM 41.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to an analog terminal device that A/D converts analog values obtained by a plurality of analog sensor elements and transmits them as digital value data by multiplex transmission. It is something.

[Prior art] Conventionally, when analog values taken in from analog sensor elements are A/D converted and sent as digital values through multiplex transmission, the format of the transmitted data is not fixed because a dedicated LSI or dedicated microcomputer is used. Ta.

For example, in the case of an analog terminal for a smoke detector used in a conventional fire alarm system, there are two analog inputs.

The data returned from the analog terminal to the base unit consists of 8 bits, with the upper 2 bits containing the sensor type and the lower 6 bits containing data indicating the smoke density detected by the smoke detector. . This format is only used in analog terminals for smoke detectors used in conventional fire alarm systems, so a dedicated LSI or microcontroller developed for this analog terminal can be used with other analog terminals. It is difficult to use it for

[Problems to be Solved by the Invention] As described above, in the conventional technology, the format of transmission data is fixed, and
Each analog has different specifications because it can only be used as an SI or dedicated microcontroller.

For each terminal, it was necessary to develop a dedicated LSI or a dedicated microcomputer with a unique transmission format.

The present invention has been made in view of these points, and its purpose is to enable the format of transmission data to be freely set in an analog terminal device having a plurality of analog inputs, thereby supporting various uses. There are things I can do.

[Means for Solving the Problems] In order to solve the above problems, in the analog terminal device according to the present invention, as shown in FIG. 1, a plurality of analog sensor elements 1a, 1b, An A/D converter 2 that converts analog values obtained by each analog sensor element 1a, lb into digital values, and a multiplex transmission circuit 3 that transmits digital value data obtained by A/D conversion by multiplex transmission. and a setting circuit 4 for setting a transmission format for transmitting data.

Note that at least one of the plurality of analog sensor elements 1a, 1b may be replaced with a variable resistor 5, as shown in FIG.

[Function] In the present invention, as described above, the analog values obtained by the plurality of analog sensor elements 1 ayl b are
Setting port #! for setting the transmission format for transmitting data in an analog terminal device that transmits converted digital value data by multiplex transmission. 4, the format of the transmitted data can be freely changed depending on the number and type of analog sensor elements 1a and lb used. Therefore, one analog terminal device can transmit any number of
It can accommodate any type of analog sensor element.

Furthermore, if at least one of the plurality of analog sensor elements 1a, lb is replaced with a variable resistor 5, it becomes possible to set the type of analog terminal device using the variable resistor 5.

[Example] FIG. 1 shows an example of the present invention. In the figure, 6 is a general-purpose LSI for analog terminal equipment, and is equipped with a plurality of analog input terminals. 1 a and 1 b are analog sensor elements that detect analog values such as smoke concentration and room temperature, and supply them as voltage signals to the above-mentioned analog input terminals. 2 is A/
It is a D converter and converts the voltage signal from each analog sensor element 1a, lb into a digital value. Reference numeral 3 denotes a multiplex transmission circuit, which performs data communication with the base unit 8 via a transmission line 7 using a multiplex transmission method. 41 is an E2PROM, which stores a set transmission format for data transmission. 42
is an optical wireless receiving circuit that receives a format setting signal sent by an optical wireless signal and writes the format setting contents to the E2PROM 41. 43 is a light receiving element, which receives an optical wireless signal. Reference numeral 44 denotes an optical wireless transmitter, which sets the transmission format of transmission data and enables transmission as an optical signal.

In this example, two analog sensor elements 1a.

I am using 1b. In this case, two sensor elements 1
The transmission format for transmitting digital value data obtained by A/D converting the analog values obtained from a and 1b differs depending on the purpose of each sensor system. Once done, the transmission format is selected according to the purpose of optical wireless transmission. As a result, as shown in FIG. 2, the format for transmitting the data A and B of each sensor element 1a1b can be freely configured. In the case of format (2), data A of the sensor element 1a is transmitted as a 2-bit value, and data B of the sensor element 1b is transmitted as a 6-bit value. That is, the data A of the sensor element 1a is transmitted as a value in 4 stages, and the data B of the sensor element 1b is transmitted as a value in 64 stages. In the case of format (2), data A of the sensor element 1a is transmitted as a 4-bit value, and data B of the sensor element 1b is transmitted as a 4-bit value. In the case of format (2), data A of the sensor element 1a is transmitted as a 3-bit value, and data B of the sensor element 1b is transmitted as a 5-bit value. Furthermore, there may be a case where only the data A of the sensor element 1a is transmitted, and in this case, the format is set to ■.

Similarly, there may be a case where only the data B of the sensor element 1b is transmitted, but in this case, the formant is set to ■.

In this way, when the transmission format is set from the optical wireless transmitter 44 according to the purpose of the sensor elements 1a and lb, the optical wireless signal is received by the light receiving element 43, and the optical wireless signal is transmitted based on the transmitted optical wireless signal. The reception circuit 42 changes the transmission format of the transmission data to E.
Written to 2PROM41. The multiplex transmission circuit 3 inputs the analog data of both sensor elements 1a1b, and transmits the analog data of the sensor elements 1a and 1b according to the format set in the E2PROM 41.

That is, in this embodiment, the setting circuit 4 is constituted by 41 to 44.

Although the above is an example of setting using the optical wireless transmitter 44, it is also possible to set this transmission format by multiplex transmission from the base unit 8. In other words, normally the data of sensor elements 1a and 1b is transmitted in 4 bits each as in format ①, but when sensor element 1
If you see any changes in the data of a, format it using remote control from the base unit 8 to obtain more accurate data.
It is also possible to set the data of the sensor element 1a and transmit only the data of the sensor element 1a as 8-bit data.

FIG. 3 shows another embodiment of the invention. In this embodiment, the above-mentioned general-purpose LSI 6 is used as an analog terminal device for a smoke detector of a fire alarm system. In the case of an analog terminal for a smoke detector, the format of the transmitted data is as shown in FIG. 4, where the upper two bits indicate the type of sensor and the lower six bits indicate the smoke density. Therefore, in this embodiment, the type of smoke sensor is set by the variable resistor 5, and the smoke concentration is input by the sensor element 1b. That is, the general-purpose LSI 6 described above has two analog input terminals, one of which is connected to the sensor element 1b, and the other analog input terminal is connected to the variable resistor 5. Thereby, compatibility with smoke detectors of conventional fire alarm systems can be ensured.

Note that the multiplex transmission method used in this type of sensor system is well known, and therefore, for example, a time division multiplex transmission method may be used, although not particularly shown. In this method, one ff1i8 and multiple multiplex transmission circuits 3 are connected using 2! ! The main unit 8 sends a start signal indicating the start of signal transmission, an address signal for specifying the multiplex transmission circuit 3 to communicate with, and controls the operation of the multiplex transmission circuit 3. A time division multiplex transmission signal is sent to the transmission line 7, including at least a control signal for the transmission, a reply time period for receiving the reply signal from the multiplex transmission circuit 3, and an end signal indicating the end of signal transmission. The address signal and control signal are composed of a plurality of bits of serial signals in which, for example, a common voltage pulse means "'1" and a short voltage pulse means "0". During the reply time period, for example, the main unit 8 side applies a voltage between the transmission lines 7, and the multiplex transmission circuit 3 side short-circuits the transmission lines 7 via a resistor, thereby increasing the required current. A multi-bit serial signal in which the pulse means "1 pulse and short current pulse means 0" is sent back to the base unit 8. Address signals and control signals are sent out from the main device 8 as low impedance voltage signals, and each multiplex transmission circuit 3 obtains an operating power source by connecting a rectifier and a smoothing capacitor between the transmission lines 7. Parent v! The address signal included in the time division multiplex transmission signal sent from 18 is
Each multiplex transmission circuit 3 is polled cyclically, and only one multiplex transmission circuit 3 with a matching address signal performs a control operation and a reply operation according to the control signal. When the multiplex transmission circuit 3 receives the start signal from the transmission line 7, it receives the following address signal and compares it with its own address signal. If the address signals do not match, wait for the next start signal to be received. If the address signals match, a subsequent control signal is received, and depending on the control signal, either the normal fire monitoring operation or the formatting operation described above is selectively performed. In other words, the above-mentioned format setting signal by remote control is transmitted as a control signal from the base unit 8. Further, during the reply time period, data detected by the analog sensor element and data indicating the type of sensor are transmitted in the format shown in FIGS. 2 and 4.

[Effects of the Invention] The invention according to claim 1 provides an analog terminal device that multiplex transmits data of digital values obtained by A/'D conversion of analog values obtained by a plurality of analog sensor elements. Since a setting circuit is provided to set the transmission format for transmitting data, the same analog terminal device can be used for various applications with different numbers and types of analog sensor elements. Therefore, there is an effect that the development time and development cost of analog terminal devices can be reduced.

In addition, in the invention as claimed in claim 2, by replacing at least one of the plurality of analog sensor elements with a variable resistor, not only the data of the detected value obtained by the analog sensor element but also the type setting This has the advantage that it is possible to transmit data for

Note that if the format setting is performed by remote control from the base unit, highly accurate data as required can be transmitted in response to a request from the base unit, and the reliability of the system can be improved.

[Brief explanation of the drawing]

FIG. 1 is a block circuit diagram showing a schematic configuration of one embodiment of the present invention, FIG. 2 is an explanatory diagram showing various transmission formats used in the same, and FIG. 3 is a schematic diagram of another embodiment of the present invention. The block circuit diagram shown in FIG. 4 is an explanatory diagram showing the transmission format used in the same. 1 a and 1 b are analog sensor elements, 2 is an A/D converter, 3 is a multiplex transmission circuit, 4 is a setting circuit, 5 is a variable resistor, 6 is a general-purpose LSI, 7 is a transmission line, and 8 is a main unit. be.

Claims (2)

[Claims] (1) Multiple analog sensor elements, an A/D converter that converts the analog values obtained by each analog sensor element into digital values, and the data of the digital values obtained by A/D conversion are transmitted by multiplex transmission. An analog terminal device comprising: a multiplex transmission circuit for transmitting data; and a setting circuit for setting a transmission format for transmitting data. (2) The analog terminal device according to claim 1, wherein at least one of the analog sensor elements is replaced with a variable resistor.