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Step 2: connect the Rx pin on RFD 900 to the TX pin configured for the UART communication, and the Tx pin on RFD 900 to the Rx pin configured for the UART communication on STM32.
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Step 3: call the standard library function
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Step 2: connect the Rx pin on RFD 900 to the TX pin configured for the UART communication, and the Tx pin on RFD 900 to the Rx pin configured for the UART communication on STM32.
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Step 3: call the standard library function
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