How to establish a communication connection between Mitsubishi PLC and PC
Due to its high performance and high reliability, PLC has been widely used in industrial control, from simple logic control to logic control, process control, servo control, data processing and A multi-function controller with integrated network communication functions. . Since the PLC itself does not have a display function, it is particularly important to realize the display of its internal data, which becomes a difficult point in the design of the PLC control system. In the PLC control system, the contents to be displayed mainly include a timer value, a counter value, and a data register value. The data display method of the present invention can be summarized into two basic types: one is a PLC-based data communication interface, such as RS-232, RS-485/422, and the display device also has such an interface, and the data display is through data communication. Realized. The use of data communication interface for data transmission and display is an effective way to achieve PLC data display. Currently mainstream PLCs provide standard RS-232 or RS-485/422 interfaces, or add these interfaces through expansion modules. The communication modules 232ADP, 232BD, 485BD, and 485ADP of the Mitsubishi FX2N can be used as a data interface. The display device can be equipped with a dedicated smart display and a general purpose computer (PC). Directly select the display screen or touch screen that matches the PLC, which can realize centralized display of various data inside the PLC, and edit the screen graphics through the editing software to improve the display interface. Visibility. The FX Series can be configured with the F93000T-BWD, F940GOT-LWD and F940GOT-SWD. The intelligent display reads the PL register through the communication interface, and the data display efficiency is high, which simplifies the design of the control system. 1:1 one station, distance & lt;; 15 meters, driven by the programming port. Communication via the programming port (no programming plc required). 1: n multiple sites (up to 16 sites), 50 meters & gt; distance & gt;; 15 meters, driven by FX485. 1: n multiple stations (up to 16 stations), 500 meters and gt; distance & gt;; 50 meters, driven by FX485. 1: n multiple stations (up to 16 stations), 1200 meters & gt; distance & gt;; 500 meters, driven by FX485 (plus 485 relay). The RS485 connection can be one or two pairs of wires. The design uses two pairs of wires for the purpose of determining the wiring method. The communication address and communication parameters can be set in the "PLC/Serial Port Settings" menu of the PLC programming software. The communication address and communication parameters can also be set directly in the software by programming (MOV instruction) to establish the PLC and the station. Communication connection between Wang Group. The specific settings of RS485 include:
The baud rate is set to 9600 bits/second, the data bits are set to 7 bits, the 1-bit start bit, the 2-bit stop bit and the even parity bit (using protocol 1). Set using the programming software, where the communication address is set in D8121.