Communicate devices using RS485

Hello, i am using quectel EC21 in which i want to communicate using Uart (RS485) but given api is valid for RS232.Is Rs485 APi are available kindly guide me .

You can use a USB to RS485 converter directly, or you can also use an RS232 to RS485 converter.

but in RS485 we also use slave address along with file descriptor ,data and data length so your given example (example_uart) the function that use to read and write take 3 argument that is file descriptor ,data and data length no slave address argument is present

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