Configuration software RS485 communication can not?

About 485 (RS485 converter) communication problems?

First, use the configuration software to do the monitoring project, mainly to take the field instrument data, the instrument has 485 interface, but there is no such instrument type in the configuration software, how can we read the meter data (485 communication mode)?

Answer: 1. The force controller itself has the driver for this instrument. This is the simplest method (usually without the instrument driver).

2. Force control does not have a drive, but the instrument supports modbus protocol. Then it will follow modbus communication (if the instrument supports standard Modbus communication protocol, the force control driver can directly select Modbus communication. The serial port parameters are set correctly.)

3, force control is not driven, the instrument provides communication protocol, then in the force control using script programming to solve the communication problem (meter manufacturer command parameters and response data format, buy a 232 to 485 conversion line, then directly connected to your computer also)

Second, what is the relationship between 485 and MODBUS?

Answer: The RS458 can be understood as a physical link and Modbus is an application layer protocol.

Third, the standard 485 interface is what the answer: RS485 uses differential signal negative logic, +2V ~ +6V represents "0", -6V ~ -2V represents "1". RS485 has two wiring and four wiring two wiring, four-wire system is a full-duplex communication, two-wire system is a half-duplex communication.