為實現實時數據的遠程采集與顯示，設計了基于Modbus 協議和RS-485 總線為基礎的智能數據采集模塊，能夠采集PT100 信號或4~20mA 的工業標準信號。其硬件系統主要由單片機、A/D 轉換、通信、存儲、電源、輸入輸出顯示及復位看門狗等模塊組成。該系統可存儲設置的參數，采集現場的模擬量，轉換為數字量進行運算處理，與上位機通信功能強大，功耗小、抗干擾能力強，接入方便，適用于一般的工業現場，滿足用戶不同的需求。
關鍵詞：單片機；Modbus 協議；數據采集；模塊

Abstract：In order to achieve real-time remote data acquisition and display, an Intelligent Data Acquisition Module based on the Modbus protocol and RS-485 bus is designed, which is capable of gathering PT100 signal or the 4~20 mA industry standard signal. Its hardware system mainly consists of the MCU, the A/D converter, and the modules for communication, storage, power supply, I/O display and reset watchdog, etc. It can save pre-defined parameters, gather the analog data on-site and convert them into digital data for processing, with rich communication functions to the main computer. Its low power consumption, strong anti-interference ability and easy integration options make the system perfect for deployment in general industrial sites to meet various user needs.
Key words：micro control unit; Modbus protocol; data acquisition; module