KR20030057500A - Local area multiple wireless communication module based on master slave concept - Google Patents

Abstract

PURPOSE: A short distance multi-to-multi wireless communication module by using master-slave concept is provided to control simultaneously a plurality of control-measuring module by wireless by using a remote control module. CONSTITUTION: An MPU1(Main Processor Unit)(10) is a main control unit and communicates with a PC(Personal Computer) and a control measuring module. The MPU1(10) also compresses or restores commands of PLC and the like. An MPU2(20) controls an RF communication module and charges a wireless communication part. The RF module(30) enables a channel to change through the PLL control until 425.26 Mhz to 447.98Mhz as a use frequency band and use a weak electric wave. The MPU2(20) changes a frequency by controlling the PLL of the RF module and transmits/receives TX and RX signal with an RS232 type to/from the RF module. Also, the MPU2(20) determines one's own ID by reading an ID-switch value upon power-on. The ID-switch(60) is a 8bit dip switch type and determines whether a device is a master communication control device or a slave communication control device or which group slave device.

Description

Local area multiple wireless communication module based on master slave concept

A technology for controlling communication at a short distance by wireless remote control when controlling a large number of modules in a facility outdoors where noise is not severe

In the prior art, the following two methods are used as remote control methods.

(1) infrared communication method

Conventional wireless communication uses an infrared communication module 360 connected to the control base plate 370 of the module as shown in FIG. As such, when the control module is controlled outdoors using an infrared communication module, sunlight acts as a noise of communication, and even when there is an obstacle, there is a disadvantage that communication is not possible and the communication distance is short and is mainly used indoors.

(2) Method of connecting wireless communication device to serial port

In this case, there is no patent or utility model, but it can be used. The method is to use the RF communication module (330, 340) having a serial communication function of the RS232 method connected to the serial port. However, only 1: 1 communication is possible, and many modules cannot be controlled and there is no function to compress command codes such as PLC, which makes noise more likely during communication and slows down the transmission and transmission speed of commands.

When using the remote control module for the control and measurement of outdoor facilities such as outdoor civil engineering control, plastic house remote control, as shown in Figure 4, wirelessly control multiple control-measurement modules simultaneously.

. Remote control uses RF of FSK method, and uses frequency band of 425MHz ~ 447MHz and weak radio wave.

. RS232C communication port which is a serial port of measuring device is used for PLC RF communication control.

. The communication control distance is within 150m, which is short distance, and therefore the radio waves use the weak electric board, so there is no radio charge or call cost.

. In order to shorten PLC control code, shorten command codes such as PLC.

. The invention is equipped with a 16-bit MPU with built-in A / D and D / A functions in addition to the serial communication function, enabling measurement and output of analog sensors.

. Simultaneous communication control of 32 control-measurements is possible and master-slave-partial polling method is invented and used as communication protocol.

1 is a device for controlling short-range wireless communication

2 is a protocol explanatory diagram of a multi-radio telecommunication control device

3 is a block diagram of the control layer of the microprocessor unit of the multiple wireless remote control unit

4 is a diagram showing the installation of a multi-radio remote control device

5 is a wireless control method using a conventional RF module

6 is an operation flowchart of a master communication control station of a multi-telecommunication device;

7 is a flowchart illustrating an operation of a communication control device of a receiver slave (SR) unit in a slave group.

8 is an operation flowchart of an intermediate slave (S) communication control device of the slave group

9 is a flowchart illustrating operations of a passive slave (ST) communication control device among slave groups.

10 is a communication command frame of PLC

11 is a compressed PLC communication command

Invented short range wireless remote multiple control measurement module communication control device as shown in Figure 1 is largely MPU1 (10, microprocessor 1) and MPU2 (20), RF communication module (30), ID switch 60 and ROM ( 80), RAM (90) and so on.

The MPU1 10 communicates with a PC or a control measurement module as a main control unit, compresses or restores commands such as a PLC, and the MPU2 controls an RF communication module and is in charge of a wireless communication part.

The RF module 30 can change the channel through the PLL control up to 32 channels in the frequency band of 425.26Mhz to 447.98Mhz, and uses weak radio waves.

The MPU2 (20) changes the frequency by controlling the PLL of the RF module, and transmits / receives TX and RX signals in RS232 format to the RF module. At power-on, the ID-switch is read to determine its own ID.

The role of the ID-switch 60 is an 8-bit dip switch, which is an ID switch that determines whether it is a master communication control device, a slave communication control device, or a group of slave devices.

MPU1 (10) communicates serially with PC or control measurement module (80) and can read sensor signals around by using built-in AD converter, and receives serial data of PC or control measurement module (MPU2) 20) to send.

The control programs inside the MPU1 10 and MPU2 20 have a control layer structure as shown in FIG.

The control layer is composed of three layers: the H / W control layer 230, the wireless medium control layer 240, and the communication protocol control layer 250.

The H / W control layer 230 is in charge of the MPU2 (20) and the RF module frequency control through the PLL control, RF transmission and reception of the Rx / TX data and the ID-switch 60 under pressure to determine the unique ID .

The algorithms of the wireless medium control layer 240 and the communication protocol control layer 250 are performed at the MPU1 10.

The wireless medium control layer 240 generates and analyzes BCC codes to detect communication data errors, converts S / W Menchester codes, and generates preamble codes in data frames, and protocols for remote communication of multiple control measurement modules. It is built.

The communication protocol control layer 250 interprets the PLC commands and has a built-in kernel for A / D converter control for measurement and communication control with the PLC 80 or the PC 80.

The wireless communication module 30 uses a weak radio wave of 10mW or less, uses a frequency of 400Mhz, and can communicate within 150m of the outdoor, and the communication speed is as low as 9600bps. The frequency has 32 channels and the frequency is controlled by PLL control.

When multiple control measurement modules communicate with each other, they must communicate with each other at their own frequencies. In this case, each time the control measurement module to be communicated changes, each frequency must be changed. However, in terms of the time required, it takes more time to change the frequency through the PLL than the data communication time in the communication control of the wireless RF communication module. Therefore, in the present invention, as a method for communication between a plurality of PLCs, the concept of a master-slave commanded by the main control unit and a method of communicating between slave controllers are facilitated while the frequency change for communication is as small as possible. .

The overall communication protocol description is as shown in FIG. As shown in the figure, the concept is that the communication control device 100 set as the master unit, which is the main control unit, and the PLC or control device set as 32 or less slaves communicate many to many, and the master communication control device The three slave devices 110, 111, and 112 each form a group 150 around the 100 to communicate with each other.

In the slave device group, four devices such as the slave reception device SR 110, the slave transmission device ST 112, and the slave device 111 and the master device each form one small loop 150. A group as shown in FIG. 2 is formed to form one entire network.

As shown in FIG. 6, the master communication device M 100 is connected to a PC or a controller and issues commands to all slave communication devices, receives data from any slave communication device, or transmits commands or data to another slave communication device. It plays a role. First, the master communication device initially sets the fundamental frequency to f0, and as shown in FIG. 2, the SR communication frequency of all the slave communication groups is also set to the fundamental frequency f0 and is commanded by the master communication device. When the master communication device 100 issues a command, the master communication device 100 transmits the group ID, the ID of the slave communication device of the group, and the command to each of the received slave communication control devices SR 110, 120, 130, and 140 of the slave group. If it is desired to communicate with a specific slave communication device, the master communication device 100 hops the frequency at the transmission frequency of the transmission slave communication control devices ST 112, 122, 132, and 142 of the corresponding slave group. And waits for data reception of the corresponding transmission slave communication device. If the data is received normally, check the ID and group in the received data and execute the command. If data is transmitted to all slave groups instead of communicating with a specific slave communication device, the master communication device is switched to a mode of receiving data of all slave groups, and thus, the transmission slave communication device SR of each slave communication device group. It sequentially changes to frequency and waits for data reception of all slave groups.

The operation flowchart of the receiving slave communication device 110 in the slave communication device group is described in FIG. As shown in the figure, initially, the frequency is set to f0 for communication with the master communication device, and receives data of the master communication device. When receiving the data of the master communication device 100, it checks whether it is its ID, and if it is its ID, it performs the corresponding command. The command transmits the command confirmation data to the next slave communication device 111. At this time, the frequency hops to the frequency f1 of the slave communication device 111 to be connected next. If it is not its ID, data is transmitted to the slave communication device 111 to be connected next.

8 is a flowchart illustrating the operation of the intermediate slave communication device 111 in the slave communication device group. The slave communication device 111 receives data from the receiving slave communication device 110 which is the front end. At this time, the frequency setting is set equal to the transmission frequency f1 of the receiving slave communication apparatus 110 in the preceding stage. When the data is received, first of all, the ID data portion of the data frame is checked to determine whether it is its own ID. If it is the ID of the self-signed device, the command is executed and the performance confirmation data is transmitted to the next transmission slave communication device 112. If it is not its ID, the received data is transmitted to the next transmission slave communication device 112. At this time, the frequency is changed to f2 which is a frequency for communicating with the transmitting slave communication device.

9 is a flowchart of the operation of the transmitting slave communication device 112 in the slave communication device group 150. The transmitting slave communication device 112 communicates with the slave communication device 111 and the master communication device 100 which are front ends. In this device, the frequency is set to be equal to the transmission frequency f2 of the slave communication device 111, which is the front end at the time of initialization, and the communication data of the front end 111 is received. If the ID is one of the received data, the command is executed. Otherwise, the received data is transmitted to the master communication device as it is. The communication frequency at this time is changed to the transmission frequency f3 of the transmission slave communication apparatus ST112.

10 shows a data frame controlling a PLC via a serial port. As shown in FIG. 10, the data includes the ENQ corresponding to the start byte, the station number of the control measuring module asking which control module is the control byte, the control measuring module command, the EOT corresponding to the stop byte, and the BCC for checking the communication error. .

Figure 11 relates to the shortening of the PLC instruction carried out in the present invention. As shown in the figure, PLC's command is converted into code for wireless communication as follows. First of all, the station number of the PLC is not placed, and the station numbers of all the PLCs are determined by the ID switch 60 of the radio communication control apparatus shown in FIG. The PLC data frame contains only the ID, command, and BCC of the wireless communication device, and preamble data is placed three bytes before and after the frame to stabilize communication of the wireless communication. The communication frame in the PLC communicates according to the PLC communication standard, and this data is converted by the wireless communication control device of FIG. 1 and again converted by the wireless communication control device according to the PLC communication standard when the PLC is controlled by the converted data. .

It is useful for wireless remote control of many control measurement modules in short distance. Multi-channel near field communication wireless communication module device is attached to external serial port of PLC for outdoor electronic board control, outdoor civil engineering control, plastic house control, etc. to easily control communication, and to control PLC to improve communication speed. Compression, restoration and analysis of the code was built in. In addition, we have invented a master-slave-partial polling protocol for efficient wireless control of up to 32 control measurement modules. In the present invention, since the weak communication wave is used as short-range communication, it is possible to wirelessly remotely control a plurality of control measurement modules within a radius of 150 m and does not require a frequency fee.

Claims (3)

In wireless communication control device using weak radio wave and multi-channel RF module when wirelessly controlling several control measurement modules at short range within 150m, wireless communication control device connected to multiple PCs is connected to one master and multiple slaves. Device to set up and communicate In a device for wireless telecommunication control of a plurality of control measurement modules in a short distance, the wireless communication control device is set to the master 100 and the slaves (110, 111, 112) and the three slave wireless communication control device and the master wireless communication control device in one loop And forming a slave group to form a slave group and tying these slave groups to control all the control measurement modules through a network. The three slave communication devices in the slave wireless communication group are defined as the receiving slave communication device 110, the slave communication device 111, and the transmitting slave communication device 112 so that the receiving slave communication device 110 is the master communication device 100. ) Only communicates with the slave communication device 111 of the next stage, and the slave communication device 111 of the next stage communicates only with the receiving slave communication device 110 and the transmitting slave communication device 112, which are the previous stages, and the transmitting slave. The communication device 112 communicates with the front end slave communication device 111 and the master communication device 100.