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On STM32F405 MCUs there are USART ports as well as UART ports available. If I need to implement RS-485 communication then which one of these should be used, USART or UART? Or are both of them equally good for RS-485 communication?

I have searched through the datasheet as well as reference manual for the MCU, but it does not provide additional information regarding the RS-485 implementation.

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    \$\begingroup\$ Why is this question tagged with "3.3v"? How is this relevant? \$\endgroup\$ – Peter Mortensen Feb 25 at 12:27
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It doesn't matter as even if you're using a USART (which provides an additional CLK pin for synchronous operation) you'll only be using the UART part (RXD/TXD). Keep in mind that you'll need an additional pin for the Data Enable signal.

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    \$\begingroup\$ If you use full-duplex RS485, then you don't need a data enable signal. You only need one for half-duplex RS485 \$\endgroup\$ – Toor Feb 25 at 5:36
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    \$\begingroup\$ @Toor For practical purposes, RS-485 without data enable signal would be RS-422. \$\endgroup\$ – CL. Feb 25 at 9:05

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