What is the RS-422 standard?
What is the RS-422 standard?
RS-422, also known as TIA/EIA-422, is a technical standard originated by the Electronic Industries Alliance that specifies electrical characteristics of a digital signaling circuit. RS-422 specifies differential signaling, with every data line paired with a dedicated return line.
What is a RS-422 interface?
RS422 interfaces were developed for serial high-speed data transmission over great distances and are increasingly used in industrial applications. A maximum of ten RS422 devices can be connected in parallel with a sender within a transmission direction.
How long can a RS-422 cable be?
1200 meters
RS422 and RS485 specified maximum cable length is 1200 meters. The maximum working data rate (in bits per second – bps) depends on network devices characteristics, cable capacitance and installed termination resistors. The longer the communication cables, the lower the maximum data rate.
Is RS-422 an NMEA?
The NMEA 0183 Standard, along with RS-232, RS-422, etc., belongs to the class of “Asynchronous Serial” interfaces. This means that data is transmitted serially (bit-by-bit) on a single line. NMEA 0183 originally allowed “single-ended” drive, but was later updated to differential drive (RS-422).
Can I connect RS232 to RS422?
RS232 to RS422/485 Conversion Cable Connection Requires No External Electronics or Power. In many cases where an RS232 to RS422/RS485 connection is required it is possible to perform the signaling conversion without an external adapter and power supply using the interface connections shown below.
Can I use RS232 cable for RS422?
Extending the transmission distance up to nearly 4000 feet (1200m) is possible with a RS232 to RS422 converter. This is where a Master/Slave multi-drop RS422 converter configuration can be used to control up to 32 devices over a distance of 4000 feet (1200 meters.)
Additionally the RS422 standard allows for line impedances down to 50 ohms while supporting the high data rates. To enable the differential driver to be used, the RS-422 standard uses a four conductor cable.
How far can RS422 transmit data?
However using reduced data rates, RS422 is able to transmit data over distances of 4000 feet (~1220 metres): the maximum is 100 kbps at this distance. The key reason why RS422 is able to achieve these improvements results from the use of differential or balanced transmission techniques.
What is an RS-422 multidrop network?
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). This bus needs only two wires for differential voltage signals.
What are the outputs of an RS-422 or RS-485 driver?
An RS-422 or RS-485 driver supplies two outputs, A and B, illustrated in Figure 4. When the driver receives a logic-1 signal at its input, V A > V B.
