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Step 1: choose a USART port in STM32 Port. Select the mode to be Asychronous. Please make sure that the Buad rate is the same between two devices.
note the buad rate used for transmit between device is 46000kbits/s. Inside the rfd config tool it is called the air rate.
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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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