What is the difference between RS-232, RS-422, and RS-485?

General Discussions
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For the electrical engineers out there, what’s the difference between the 3 communication protocols?

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RS-232 is a standard for serial data communication that uses a single-ended cable with 9 or 25 pins and supports data transmission speeds up to 20 kilobits per second (Kbps). RS-232 is commonly used for short-range communications between a computer and peripheral devices, such as a mouse, keyboard, or modem.

RS-422 is an improved version of RS-232 that uses differential signaling, which provides better noise immunity and longer cable lengths. RS-422 supports data transmission speeds up to 10 Mbps and can support distances up to 4,000 feet. This standard is often used in industrial automation and control systems.

RS-485 is a newer standard that is similar to RS-422, but it uses differential signaling over a twisted-pair cable, allowing multiple devices to communicate over a single cable. RS-485 supports data transmission speeds up to 10 Mbps and can support distances up to 4,000 feet, with the possibility of even longer distances depending on the specific implementation. RS-485 is commonly used in industrial control systems and building automation systems.

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@alexis-mikakos where do you use these protocols?

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PMS, DP system, etc. Just preparing for my ETO exam.

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