PXI-8423 777737-02 NI RS-485接口

RS-485接口是一种在工业自动化领域中常用的通信接口标准，它属于OSI模型物理层。RS-485接口标准由电信行业协会（TIA）及电子工业联盟（EIA）联合发布，定义了平衡数字多点系统中的驱动器和接收器的电气特性。

RS-485接口具有以下特点：

1. 半双工通信：RS-485接口只能以半双工方式进行通信，即发送和接收不能同时进行。
2. 远距离通信：RS-485接口支持长距离有效率的通信，最远可达1200米。
3. 多点通信：在一个网络上最多可以有256个RS-485接口节点。
4. 抗干扰能力强：RS-485接口采用平衡驱动器和差分接收器，具有很强的抗共模干扰能力。
5. 总线结构：RS-485接口采用总线型结构，可以方便地构成多机通信系统。

在使用RS-485接口时，需要注意以下几点：

1. RS-485接口需要使用双绞线作为传输媒介，以减少电磁干扰。
2. 在进行通信时，需要将各个RS-485接口的地址设置不同，以避免冲突。
3. RS-485接口的驱动器在发送数据时需要将数据转换成电信号，接收器则需要将电信号转换成数据信号。因此，需要使用相应的转换芯片来实现电信号和数据信号之间的转换。

总之，RS-485接口是一种在工业自动化领域中常用的通信接口标准，具有半双工通信、远距离通信、多点通信、抗干扰能力强、总线结构等特点。在使用时需要注意使用双绞线作为传输媒介、将各个接口的地址设置不同、使用相应的转换芯片等。

PXI-8423

RS-485 interface is a common communication interface standard in the field of industrial automation, which belongs to the physical layer of OSI model. The RS-485 interface standard, published jointly by the Telecommunications Industry Association (TIA) and the Electronic Industries Alliance (EIA), defines the electrical characteristics of drivers and receivers in balanced digital multipoint systems.

The RS-485 interface has the following features:

Half-duplex communication: The RS-485 interface can only communicate in half-duplex mode, that is, sending and receiving cannot be carried out at the same time.
Long-distance communication: The RS-485 interface supports efficient communication over long distances, up to 1200 meters.
Multipoint communication: There can be up to 256 RS-485 interface nodes on a network.
Strong anti-interference ability: The RS-485 interface uses a balanced driver and differential receiver, which has a strong ability to resist common mode interference.
Bus structure: RS-485 interface adopts bus structure, which can easily constitute multi-machine communication system.
When using the RS-485 interface, note the following:

The RS-485 interface requires twisted pair as the transmission medium to reduce electromagnetic interference.
During communication, the addresses of each RS-485 interface need to be set differently to avoid conflicts.
The driver of the RS-485 interface needs to convert the data into an electrical signal when sending data, and the receiver needs to convert the electrical signal into a data signal. Therefore, it is necessary to use the corresponding conversion chip to achieve the conversion between electrical and data signals.
In short, RS-485 interface is a common communication interface standard in the field of industrial automation, with half-duplex communication, long-distance communication, multi-point communication, strong anti-interference ability, bus structure and other characteristics. In use, it is necessary to pay attention to the use of twisted pair as a transmission medium, the address of each interface is set differently, and the corresponding conversion chip is used.