In the field of industrial control, it is not only necessary to realize data communication between the central computer and the field equipment, but also the demand for data communication between the equipment far away from each other. Based on comway communication platform and VPN communication software, our products can realize one-to-one or one to mulitpoint communication functions between serial port or network port devices。

    Each field device is connected to comway data server through DTU, comway virtual serial software is installed on a computer that can access the Internet, and the mutual mapping relationship of dtu-dtu is added, so as to realize one-to-multi or one-to-one data communication

    The one to multi communication mode is especially suitable for the communication between master and slave devices based on Modbus protocol. The master device sends query instructions and broadcasts them to each device with which the mapping is established. The Modbus slave device responds to the query instructions and returns data to the master device。

    Apply for user's private account and add DTU in comway virtual serial software. See comway virtual serial software instructions for details. It should be noted that dtu-dtu mapping cannot be established in the public account 888888, and this function can only be realized in the user's private account. Each comway virtual serial software private account can add up to 1000 DTUs by default

    First, establish a VPN network. All network port devices connected to DTU are joined to the VPN network. At this time, one-to-one or one to multiple data communication can be established based on VPN IP + communication port. The system diagram is shown in the figure below：