Research Of MSP430 485 Bus-Mastering Meter Reading System Based On Telefhone Alarm

Nowadays most of meter in China is primary traditional mechanical meter, while developed countries have been widely used digital power meter. With the rapid development of electronics and the computer technology, mechanical meter have fallen behind the pace of development of the times, and it will be replaced with digital meter. This paper is a design of MSP430 RS-485 bus meter reading concentrator based on digital meter. For the actual of industrial concentrated ammeters and their high electricity parameter, the article introduces the bus-mastering concentrative terminal of automatic reading meter and its main chip is MSP430 of low-cost power.Firstly, according to the thoughts of conversion from mechanical meter to digital meter that our county proposed and the requirements of"Multi-function watt-hour meter communication protocol"it worked out, the article carried on the overall program design. And it divides into the upper machine parts and lower machine parts adopting modular thought. PC uses a common interface management software which is mature on the market, its program is designed by C++ language using VC++6.0 as development platform, and it uses Access database technology to implement the dynamic data storage, display, backup, searching, printing and related operational control. The lower machine includes concentrative terminal of reading meter, electronic energy meter, RS-485 communication module, Infrared module, display module and the telephone alarm module.Secondly, in hardware, the article designs and implements each module. RS-485 module is the main channel in which the meter reading system exchanges data with meters. Thus the correct selection of devices is critical to the stability of the system. The system uses TI's SN65LBC184 chip with build-in high-energy transient protection. It increases the reliability of resistance to synchronize data transmission cable of the transient noise. MCU controls the telephone alarm set through relay, and the alarm set dials the police by dial pulse that the bureau's switch supports. In software, it completed the design of LCD multi-level display menu, the design of 485 communication, infrared communication and measures of data loss and power down.In the end, article tests the overall performance and data transceivers of the system. And the test results basically meet the needs of the data indicators and safety targets of the meter reading system.