sample firmware for nRF52840 that operates in a 3-wire system with only Rx and Tx for UART communication

[jojojo]

Is there a sample firmware for nRF52840 that operates in a 3-wire system with only Rx and Tx for UART communication and no hardware flow control?

[jojojo]

The 5-wire system is a system that requires RTS and CTS control. The 3-wire system is a control that does not require RTS or CTS.

[Einar Thorsrud]

I understand that you do not need HW flow control, but that (and the wire count) is also all I know. If you need more information, then please clarify the question.