KR0181746B1 - Multi-port monitoring circuit - Google Patents

Abstract

It relates to a multi-port supervisory circuit by a single line asynchronous communication method, the multi-port supervisory circuit is composed of an asynchronous serial port to one processor, and a circuit composed of a transmission method of asynchronous communication that can be sent over a long distance, the communication method It uses asynchronous serial communication method to control multiple ports located at a long distance by using a single microprocessor, so that information can be received at a port located at a long distance by a single line, and multiple port information can be received by a common line. It is easy to install in places where it is difficult to install many transmission lines.

Description

Multiport Supervisory Circuit Device

1 is a block diagram showing a multi-port control circuit by a single line asynchronous communication method according to the present invention.

2 is a block diagram showing serial data of a multiport control circuit by a single line asynchronous communication method according to the present invention.

* Explanation of symbols for main parts of the drawings

1: start signal detection circuit 2: counter

3: first shift register circuit 4: first latch circuit

5 decoder 6 second latch circuit

7: second shift register circuit 8: output data synthesis circuit

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-port control system, and more particularly, to a multi-port supervisory circuit by a single line asynchronous communication method capable of transmitting a state of multiple ports to a single processor through a single line using an asynchronous communication method.

In general, asynchronous transmission is used when the data to be transmitted occurs at irregular intervals. The user at the terminal enters each character at irregular intervals, and consecutive characters are entered between each character. It may have a long time interval.

Thus, for this type of communication, the receiver must be able to resynchronize each at the beginning of a newly received character. To this end, each transmitted character or, more generally, each item of user data is framed between one or more additional start bits.

To transmit each item of user data, 10 bits (one start and one stop bit each) or 11 bits (one start bit and two end bits) can be used. Thus, assuming a start bit, an end bit, and a bit rate for an 8 bit term, that is, 1200 bps (bits per second), the symbol rate (one symbol consists of 11 bits) is 1200/11 or 110 bytes / sec. do.

In the prior art, a system for controlling several ports has a centralized structure by a single processor, a distributed structure using independent processors for each port, and a hybrid structure in which a centralized structure and a distributed structure are combined.

However, the centralized control system has a simple structure when the number of ports is not large, so that the convergence of control information and the efficient management of the control port are convenient. However, as the number of ports increases, real-time processing becomes difficult and the structure becomes complicated. There is this.

In addition, a control system having a distributed structure can process a large amount of information for each port, but there is a problem that it is difficult to efficiently manage information input and output to each port and to implement synchronization between ports.

In addition, the conventional control system for controlling multiple ports has independent transmission lines for each port. In case of limited space, the control system is not only limited to installing transmission lines but also difficult to design mechanically. If the distance is far away, the transmission line is affected by the noise, there is a problem that the manufacturing cost increases.

Therefore, in the present invention, to solve the above problems, by monitoring the remote port by asynchronous serial communication method, and when controlling multiple systems in a narrow space to solve the difficulty of mechanical design due to the complexity of the transmission line Therefore, the aim is to solve the reliability of the system affected by external noise and to reduce the manufacturing cost.

In order to achieve the above object, the present invention provides an asynchronous serial port and a start signal detecting circuit for detecting and detecting a start bit of a communication by inputting data into a circuit configured in a transmission method of asynchronous communication capable of long distance transmission to one processor; A counter for counting the number of serial received data bits of a predetermined size including the start bit, a counter for counting the number of serial data bits that have been counted and transmitted, and a counter for converting the counted transmitted serial data in parallel A first shift register circuit, a second latch circuit for receiving counted clock data and port input data for distinguishing each port transmitted from the counter and maintaining the port input data in parallel, and parallel data transmitted from the second latch circuit; Of the first latch circuit and data transmitted from the first latch circuit. A decoder which decodes a code part and transmits it with a start detection if it is a code of a port to be monitored; a second shift register for converting parallel data transmitted from the first shift register circuit and the first latch circuit into serial data; And an output data synthesizer configured to transmit output data obtained by synthesizing serial data transmitted from the second shift register circuit and input data without a port supervisory code to a processor.

Hereinafter, with reference to the accompanying drawings will be described in detail the present invention.

1 is a block diagram showing a multi-port control circuit according to the single-line asynchronous communication method of the present invention. The start signal detecting circuit 1 receives input data and detects and detects a start bit of communication. A counter (2) for counting the number of data bits, a first shift register circuit (3) for converting serial data into parallel data, a decoder (5) for distinguishing each port, and counted clock data and ports A second latch circuit 6 for inputting and holding input data in parallel; a first latch circuit 4 for holding and holding parallel data transmitted from the second latch circuit 6; and the first shift register. A second shift register circuit 7 for converting parallel data transmitted from the circuit 3 into serial data, and an input data having no serial data and a port supervisory code transmitted from the second shift register circuit 7; It shows that it is composed of the output data synthesis circuit 8 for synthesizing the output data for transmitting to the other processor.

In the transmission method of the asynchronous communication, the processor which first makes the asynchronous communication transmission speed of each port use the function of the asynchronous serial chip, and each port is determined by the input clock of the counter.

The operation sequence of the transmission method of asynchronous communication is that when the processor sends data to the transmission line (RS232 method or RS422 method), the receiving port detects a start bit, operates a clock by the detected start bit, and operates the clock. The counted clock signal and the port input data are input to latch the parallel state. In another transmission path, the operated clock reads data continuously transmitted from a clock rising edge processor and then shifts the first shift register circuit ( Change the serial data in parallel in 3), latch the state of the input data and the port transmitted from the second latch circuit 6 to the first latch circuit 4, and from the second latch circuit 6 If the code part of the transmitted data is decoded by the decoder 5 and the code of the port to be monitored, the code is sent to the second shift register circuit 7 together with the start detection. And transfers the input data and the port monitoring data transmitted from the first shift register circuit 3 and the decoder 5 from a parallel state to a serial state, and transfers them from the second shift register circuit 7. Output data is synthesized by combining the input data and the input data without the port supervisory code. Therefore, the output data can be transmitted to the processor to check and control the state of the port to be monitored.

2 is a diagram illustrating the synthesis of a serial data of a multi-port control circuit by a single line asynchronous communication method according to the present invention. A code is assigned to each data to be sequentially transmitted to a single line. Output data is detected by inputting the data of code detected in.

According to the present invention, the multi-port supervisory circuit device using a single line asynchronous communication method can receive information from a port located at a long distance with a single line, can receive multiple port information through a common line, and it is difficult to install many transmission lines. Easy to install in place, it can be useful for factory automation system which has poor environment and needs telecommunication control.

Claims (2)

A start signal detecting circuit that receives input data and detects and detects a start bit of communication, a counter that can count the number of received data bits of a predetermined size in series including the start bit, and the counted transmitted serial data in parallel A first shift register circuit for converting to a second latch circuit, a second latch circuit for receiving and maintaining the counted clock data and the port input data that can distinguish each port transmitted from the counter in parallel, and in the second latch circuit. A first latch circuit for preserving and maintaining the transmitted parallel data, a decoder for decoding a code portion of the data transmitted from the first latch circuit and transmitting the start code with a start detection if it is a code of a port to be monitored, and the first shift Second shift register for converting parallel data transmitted from register circuit and first latch circuit into serial data Emitter and a multi-port monitoring circuit comprises an output data synthesizer for transmitting the serial data to the second monitoring port and the processor to a code output data synthesizing the input data is not transferred from the shift resist. The multi-port supervisory circuit according to claim 1, wherein the communication method is an asynchronous serial communication method.