RN4677 Will Not Transmit Data Over the UART TX Pin

If the RN4677module appears to be receiving commands over UART but is not transmitting the expected responses over the TX pin, the problem may be flow control. If the RTS and CTS pins are floating while the RN4677 module has flow control turned on (which is the default state) then the device may not think it is "Clear To Send".

To fix this, you can turn flow control off by sending the S:,00B6,00 command. Alternatively, you can connect the CTS and RTS pins to VDD and VSS pins to allow the device to constantly assume it is "Clear To Send".

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