Parameter setting method for PLC communication system

• US 5,566,176 A
• Filed: 06/26/1995
• Issued: 10/15/1996
• Est. Priority Date: 07/07/1994
• Status: Expired due to Term

• Current Assignee: LG Industrial Systems Co., Ltd (LG Corporation)
• Original Assignee: LG Industrial Systems Co., Ltd (LG Corporation)
• Inventors: Chang, Seong W.
• Primary Examiner(s): MARCELO, MELVIN C
• Application Number:
  US08/494,550
• Time in Patent Office: 477 Days
• Field of Search: 370/17, 370/79, 370/82, 370/85.1, 370/94.1, 370/99, 395/200.13, 395/200.16, 395/200.17, 395/480, 395/497.03, 395/497.04
• US Class Current: 709/228
• CPC Class Codes: G05B 19/052 Linking several PLC's
• CPC Class Codes: G05B 2219/15025 Before starting communication between modules, initialize modules

Abstract

A parameter setting method for a PLC communication system. In a transmission mode, a self-station identification number is set, and transmitting data is divided into a plurality of blocks if it exceeds a predetermined size. Block identification numbers are assigned to the divided blocks, respectively. Then, a size of a desired one of the divided blocks is set. In a reception mode, a counterpart station identification number and a desired one of the block identification numbers are set. Also, a common reception region is set. Then, an individual reception region is set as needed. After the transmission and reception parameters are set, they are read whenever a user'"'"'s program is completed. Data transmission and reception operations are performed according to the read transmission and reception parameters.

Claims

1. A parameter setting method for a PLC communication system, comprising:

a transmission parameter setting step of setting a self-station identification number in a transmission mode, dividing transmitting data into a plurality of blocks if it exceeds a predetermined size, assigning block identification numbers to the divided blocks, respectively, and setting a size of a desired one of the divided blocks;

a reception parameter setting step of setting a counterpart station identification number and a desired one of the block identification numbers in a reception mode, setting a common reception region and setting an individual reception region as needed; and

a data transmitting/receiving step of reading said transmission and reception parameters whenever a user'"'"'s program is completed after said transmission and reception parameters are set and performing data transmission and reception operations according to the read transmission and reception parameters.

2. A parameter setting method for a PLC communication system, as set forth in claim 1, wherein said transmission parameter setting step includes the steps of:

setting the self-station identification number in the transmission mode;

dividing the transmitting data into n blocks if it exceeds m bytes;

assigning the block identification numbers to the divided n blocks, respectively; and

setting a size of a desired one of the divided n blocks.

3. A parameter setting method for a PLC communication system, as set forth in claim 2, wherein the self-station identification number and the block identification number are appended in a header of the transmitting data in the transmission mode.

4. A parameter setting method for a PLC communication system, as set forth in claim 2, wherein the transmitting data has a maximum length of m bytes in the unit of block so that m*n-byte data transmission can be performed at the maximum over the entire communication stations, where n is the number of the communication stations.

5. A parameter setting method for a PLC communication system, as set forth in claim 1, wherein said reception parameter setting step includes the steps of:

setting the counterpart station identification number and the desired block identification number in the reception mode;

setting the common reception region after the desired block identification number is set; and

setting the individual reception region after the common reception region is set.

6. A parameter setting method for a PLC communication system, as set forth in claim 1, wherein said data transmitting/receiving step includes the step of receiving data in the reception mode only when a station identification number and a block identification number of the received data are the same as those set in the reception parameter.

7. A parameter setting method for a PLC communication system, as set forth in claim 6, wherein said data receiving step includes the steps of:

discriminating whether'"'"'the station identification number and the block identification number of the received data are the same as those set in the reception parameter;

discriminating whether the common reception region is set in the reception parameter, if the station identification number and the block identification number of the received data are the same as those set in the reception parameter;

receiving bytes of the received data corresponding to the common reception region if the common reception region is set in the reception parameter;

discriminating whether the individual reception region is set in the reception parameter, after the bytes of the received data corresponding to the common reception region are received;

receiving bytes of the received data corresponding to the individual reception region if the individual reception region is set in the reception parameter;

discriminating whether the reception parameter is the last one, after the bytes of the received data corresponding to the individual reception region are received; and

completing the data reception operation if the reception parameter is the last one.

8. A parameter setting method for a PLC communication system, as set forth in claim 7, wherein the common reception region is set to store a designated number of bytes of the received data into a memory location designated by a data pointer.

9. A parameter setting method for a PLC communication system, as set forth in claim 5 or claim 7, wherein the individual reception region is set to store a specified number of bytes of the received data beginning with a byte point designated by an individual region identification number.