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What is the difference between RS-422 and 485?

What is the difference between RS-422 and 485?

RS-422 can work and receive with full-duplex operation through two pairs of twisted pairs. RS485 can only work half-duplex and cannot perform transmission and reception simultaneously, but it only needs one couple of twisted pairs.

What is a RS485 transceiver?

The RS-485 specification meets the requirements for a truly multipoint communications network, and the standard specifies up to 32 drivers and 32 receivers on a single (2-wire) bus. Some RS-485 transceivers modify the input impedance to allow up to 8× more nodes to be connected to the same bus.

What is an RS485 connection?

RS-485 is a duplex communication system in which multiple devices on the same bus can communicate in both directions. RS-485 is most often used as half-duplex, as shown in the figures above, with only a single communication line (‘A’ and ‘B’ as a pair).

What does RS mean in RS-422?


Acronym Definition
RS-422 Differential Serial Interface Standard

Is RS-422 better than RS232?

RS422 (differential) was designed for greater distances and higher Baud rates than RS232. In its simplest form, a pair of converters from RS232 to RS422 (and back again) can be used to form an “RS232 extension cord.” Data rates of up to 100K bits / second and distances up to 4000 Ft.

What RS-422 485?

RS485 can have multiple Commanding Devices and multiple Listening Devices. RS422 can have only one Commander and multiple Listeners. For example, you can connect one PC (the Commanding device) to 10 temperature controllers (listeners).

How do I know if RS485 is working?

To check if your RS232 to RS485 converter (or USB to RS485 converter) is working properly you can make a loop-back test using a terminal program such as AccessPort. This way you can determine if the converter can send and receive characters properly.

Can RS485 be daisy chained?

RS485 is Two-Way The sending device can be anywhere along the daisy-chain, and receiving devices can be on both sides of the sending device, so the signals have to travel both ways along the RS485 wire pair.

Is RS-422 a protocol?

Another name of RS-422 is TIA/EIA-422; it provides standard technical support in the electronics industry. The RS422 was introduced mainly to get the higher data rates on serial data communication than the RS-232. So, we can say that the RS422 is an updated version of the RS232 protocol.

How many wires is RS-422?

In the RS-422 network, there can only be one transmitting device and up to 10 receiving devices. The RS-422 line is 4 wires for data transmission (2 twisted wires for transmission and 2 twisted wires for receiving) and one common GND ground wire.

What is the difference between RS-422 and RS-485?

The largest difference between RS-422 and RS-485 centers on the types of communications allowed. The RS-422 standard allows only one-way (simplex) communications between one driver, and as many as ten receiving devices. So if you plan to control devices and need no feedback from them, an RS-422 multidrop network will work well ( Figure 1a ).

Can RS-485 transceivers be used in industrial networks?

Abstract: RS-485 transceivers offer an easy way to implement the physical layer in industrial networks; several fieldbus standards specify an RS-485 serial port for communications.

What is RS-485 half-duplex?

The RS-485 standard allows half-duplex and full-duplex communications. A half duplex arrangement connects all receivers and drivers to the same 2-wire bus as shown in Figure 2.

Which fieldbus standards transmit over RS-485?

The following major fieldbus standards either transmit over RS-485 or include an RS-485 version among others. Attached resource computer network (ARCNET) Provides data rates up to 10Mbps.