what is the difference between RS232 and RS485?

author: Echo

RS232 and RS485 are two popular serial data communication protocols.These were established by the electornic industries Association (EIA) and are used for the communication between a system and a peripheral.But they are almost replaced with the USB standard these days.
RS485 is an advanced version of RS232. Hence RS485 was designed to solve or improve several limitations and features of RS232. An advantage of RS485 was that it suppports the same DB9 cable and connectors used by RS232. Thus it was not necessary to use different cable and connector models.
RS232 is a single-ended interface, meaning that it only uses one wire to transmit data. In contrast, RS485 is a differential interface, which means that it uses two wires to transmit data. This difference is important because it affects the maximum distance that data can be transmitted.
RS232 is limited to a maximum distance of 50 feet, while RS485 can be extended up to 4000 feet. In addition, RS232 uses a single-ended voltage swing, while RS485 uses a differential voltage swing. This means that RS485 can tolerate higher levels of noise and interference.As a result, RS485 is typically used in industrial applications where long distance and high levels of noise are present. 
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