KR100264148B1 - How to connect power line modem - Google Patents

Abstract

PURPOSE: A method for connecting a power line modem is provided to enhance compatibility with devices and efficiency of connecting with the devices by applying Hayes standard to the power line modem. CONSTITUTION: If there are data received from a power line modem, the received data are processed(11). Otherwise, a character is inputted to a memory(12). If the character is a CR(13), it is determined that there is AT in character streams stored in the memory(14). If so, the process moves to the next pointer(15). Then, if the next of the AT is not the end of character stream(16), the character and delivery variable of it are obtained(17). If the obtained character is an alphabet(A¯Z), a principal command is performed(18). If the character is &, the extended command is performed(19). If the character is S-register(S), an S-register command is performed(20). If the character is neither an alphabet character, & or S-register, an error is indicated.

Description

How to connect power line modem

The present invention relates to a method of connecting a power line modem, and more particularly, to a device connected to an RS-232 interface and a Hayes standard adopted by a telephone line modem. The present invention relates to a connection method of a power line modem to improve compatibility and connection efficiency.

In general, a power line modem is also called a power line modem and refers to a modem in which the medium of communication is a power line. It transmits the data to be transmitted to the single-phase or three-phase general household power by various modulation methods, and receives data by the corresponding modulation method, and uses the power line as it is, so there is no cost burden according to the line hypothesis, so that the short-range data Used for communication and various automations.

The Hays standard was first developed by Hayes Microcomputer Product in 1981 as a communication language for humans and modems, and is used in most telephone line modems and other modems in use today. It is a format that receives commands from the system and other data terminal equipment (DTE) devices, and consists of basic commands, extended commands, and S-registers.

Fig. 1 is a block diagram of the RS-232 protocol of a conventional power line modem, as shown therein; A destination address 2 of the partner to be connected; Its address 3 to inform the sender of its location; An instruction 4 of an operation to be executed; Data 5 to be transmitted; Referring to the related art, which consists of a terminating character 6 indicating the end of the transmission data 5, the following description is made.

A system using a conventional power line modem determines the values of the elements to transmit and receive some data, makes one string at a time, and then transmits and receives it immediately. Therefore, there is no need for connection, transmission, and termination, and whenever a transmission is needed, the transmission must be performed from time to time and the receiver must always be prepared to receive data.

For example, if you want to transfer the data 'ABCDEFG' from system 1 to system 2, the sending system sets the address of the receiving system and its own address, sets up a command called data transfer, and makes all of them as one string. To the powerline modem connected to the system.

Accordingly, the modem receiving the character string from the transmission system transmits data through the power line as it is, and all modems connected to the power line receive this data, and the modems receiving the data are received by the system connected to them. The system transmits the data and analyzes the data string to determine whether the destination address 2 is the same as its address.

However, since the conventional RS-232 protocol uses an arbitrary and independent protocol, all systems must use only the power line modem set as the protocol, and there is no compatibility with the telephone line modem. The system using the modem has to have a separate connection port, so there is a problem in that additional cost is taken in configuring the system.

Therefore, the present invention was created to solve the above-described problems, and by applying the Hayes standard, which is mostly adopted in the conventional telephone line modem, to the power line modem, the conventional telephone line modem can be connected without any special device. The purpose is to provide a connection method of a power line modem.

1 is a configuration diagram of an RS-232 communication protocol of a conventional power line modem.

Figure 2a is a block diagram of the RS-232 communication protocol of the power line modem according to the present invention.

2b is a communication link flow diagram of a power line modem according to the present invention;

3 is an operational flowchart of command execution in accordance with the present invention;

4 is a flowchart of operation of a communication connection in accordance with the present invention;

5 is a flowchart illustrating a communication connection operation of a receiving modem in the present invention.

6 is an operation flowchart of communication termination in the present invention.

A method of connecting a power line modem of the present invention for achieving the above object comprises: an environment setting step of setting a state, an option, and the like of the modem; A communication step of transmitting and receiving data by connecting a communication line with a counterpart modem and terminating the connection; It is achieved by a command performing step of receiving and analyzing and performing various commands of the environment setting step and the communication step, the embodiments according to the present invention will be described in detail with reference to the accompanying drawings.

3 is an operation flowchart of the command execution step. As shown in FIG. 3, if it is determined whether there is data received from the power line modem, the received data is processed (11). (12), and determine whether the character received in the step 12 is the return character (CR), or if not, go back to the previous step (12) and perform again (13), the start character (AT) of the string stored in the memory If it is determined that there is no, the pointer is incremented, and if it is the end of the string, it is determined that the end of the string is returned to the command execution step (14), and if there is a start character (AT) among the strings, the pointer is moved to the next (15). And if it is determined that the next character after the AT is the end of the character string, it returns to the command execution step (16), and obtains the character and its transfer variable (17). Determining whether (A to Z) is performed to execute the basic command, and if it is determined whether the performed command is an error or not, returning to step 16 of determining the end of the string by incrementing the pointer (18), and the character is represented by the alphabet. If it is determined that it is an percent character (&), an extended command is performed, and if it is determined that the executed command is an error, it returns to step 16 to determine the end of the string by increasing the pointer (19). It is determined whether or not the S-register character (S) to perform the S-register command, and if it is determined that the executed command is an error, the process returns to step (16) of determining the end of the string by increasing the pointer (20). If the character is not an alphabet, percent character (&), and S-register character (S), an error is displayed and the process returns to the step of executing the command (21).

In the communication step, the communication connection and the data communication step are operated by dial letters (D). As shown in FIG. 4, the transmitting power line modem receives a dial number of the other party (31). If there is an error in the other party's dial number, it displays various errors and returns to the command execution step (32), if there is no error, requests the connection to the other party's modem (33), and the other party's modem responds to the connection request in step (33). If not, retry after a certain period of time and display the error message when the time limit expires, return to the command execution step (34). Is connected to indicate the connection status (DCD ON) (36), and determines whether there is data received from the power line, and transmits to the system, if received from the system It is determined whether there is data (37), and if there is no data received from the power line, it is determined whether it is an online command mode character (+++) and returns to the command execution step, or is transmitted to the counterpart modem through the power line (38). (Here '+++' is a command to stop the current progress and return to online command execution.)

5 is a communication connection and data communication step of the receiving power line modem to determine whether data has been received through the power line as shown in FIG. 51, and to determine whether a connection request is made to its own address when receiving data. Otherwise, go back to the first (52), if the connection request to its address (53), the system sends a ring string (53), then counts the number of rings specified (54), connect (54), and request the connection Answer 55 to the modem, determine if data has been received from the power line after the communication connection or wait 56; determine whether the received data is a connection termination request, or transmit data 57 to the system; If the connection termination request is transmitted (58) to the system disconnection string (NO CARRIER), after the connection is terminated (DCD OFF) indicates the connection status of the modem and returns to the command execution step (59).

In the communication step, the communication end is operated by a hook character (H). As shown in FIG. 6, the connection termination request signal is transmitted to the other party modem connected as shown in FIG. If not, retry (72) the specified number of times, terminate the connection if there is a response to the termination request, send a disconnect string (NO CARRIER), and return to the command execution step (73), followed by the command The power line modem, which is configured with the following parameters, enters the command execution phase when power is applied, and processes data when data is input from the other modem.

As a result, the modem receives a command string input from the system through the RS-232 protocol. As shown in (a) of FIG. 2, the command string must include a start character (AT) to execute the commands after it, and the end step is indicated by a carriage return (CR). The command string executes the commands one at a time. If an error occurs during execution, the command string immediately leaves an error message and returns to the command execution step.

Communication connection is made by dial character (D), and communication is done by hook character (H). Power line modem has no on-hook and off-hook functions like telephone line modem. As shown in (b) of FIG. 2, communication is completed through three steps of connection, transmission, and termination.

As described above, the method of connecting the power line modem of the present invention is such that the apparatus connected with the RS-232 protocol and the Hayes standard adopted by the telephone line modem are applied to the power line modem. It is effective to increase the compatibility and efficiency of the connection.

Claims (5)

An environment setting step of setting a state and options of a modem; A communication step of transmitting and receiving data by connecting the communication and then terminating the connection; And a command execution step of receiving and analyzing and executing various commands of the environment setting step and the communication step. The method of claim 1, wherein the performing of the command comprises: processing the received data if it is determined whether there is data received from the powerline modem; If there is no received data, receiving one letter and storing the same in a memory; Determining whether the character received in the step is a return character, or if the character is returned to the previous step, performing the step again; Determining whether there is a start character among the strings stored in the memory, and if not, increments the pointer, and if it is the end of the string, returns to the step of executing a command; If there is a start character, moving the pointer to the next; Determining whether the start character is the end of a character string and returning to a command execution step when the character ends; Getting a character and its parameters; Determining whether the character obtained in the step is an alphabetic character, performing a basic command, and if it is determined whether the executed command is an error, returning to the step of determining the end of the string by incrementing the pointer; Determining whether the character is an alphabetical character rather than an alphabetical character, performing an extension command, and determining whether the executed command is an error or not, increasing the pointer to determine the end of the character string; Determining whether the character is an S-register character, performing an S-register command, and determining whether the executed command is an error, or returning to determining the end of the string by incrementing the pointer; And displaying an error and returning to a command execution step if the character is not an alphabet, a percent character, or an S-register character. The method of claim 1, wherein the communication connection and data communication in the power line modem of the transmitting side comprises: receiving a dial number of the other party; Displaying an error and returning to a command execution step if there is an error in the input counterpart dial number; Requesting a connection to the opposite modem if there is no error; Retrying after a predetermined time if the other party's modem does not respond to the connection request, displaying an error message and returning to a command execution step when the time limit expires; Transmitting a response acknowledgment after the counterpart modem responds; Connecting a modem to display its connection status; Determining whether there is data received from the power line, and transmitting the data to the system, and determining whether there is data received from the system; If there is no data received from the power line, determining whether it is an online command character and returning to the command execution step, or transmitting to the other modem through the power line. The method of claim 1, wherein the communication connection and data communication in the receiving power line modem comprises: determining whether data has been received through the power line; Determining whether a connection request is made to a user's address when receiving data or returning to the first time; Sending a ring string to the system if the connection request is to its own address; Counting and connecting a predetermined number of rings; Responding to the modem requesting the connection; Determining whether to receive data from the power line after the communication connection or waiting; Determining whether the received data is a connection termination request or transmitting data to the system; Transmitting a disconnect string to the system if the connection termination request is made; And displaying the connection status of the modem after the connection is terminated and returning to the command execution step. The method of claim 1, wherein the communication termination in the communication step comprises the steps of: transmitting a connection termination request signal to a counterpart modem connected thereto; Determining whether there is a response from the connected modem or retrying a specified number of times; If the response to the termination request, the connection is terminated, the connection method of the power line modem comprising the step of returning to the command execution step after transmitting the disconnection string.