485 communication can not be received for the following reasons:
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The 485 line is incorrectly connected. It includes the interface connected to the sensor and the interface connected to the data collector.
The data collector is faulty. Check whether the data collector works properly, including whether the collector is powered on and whether an exception message is displayed.
485 Communication parameters are incorrectly set. The parameters include baud rate, data bit, stop bit and so on.
The 485 network configuration is incorrect. Procedure The parameters include the IP address, subnet mask, and gateway.
The sensor is faulty. Check whether the sensor works properly, including whether the sensor is powered on and whether an exception message is displayed.
The device address is incorrect. On the 485 bus, each device needs a separate address. If the current device address is set incorrectly, other devices will not be able to communicate with it.
Communication protocol error. 485 devices need to implement specific communication protocols for data exchange. If the protocol is implemented incorrectly, the data cannot be correctly parsed and the communication fails.
The serial port chip or other hardware of the host is faulty or damaged. The 485 communication may fail.
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To solve the problem that 485 communication can not be received, it is necessary to check and exclude according to the specific situation.