UART21 can't receive RX data

[Metal01]

I am using the nRF54L10 chip with NSC-V3.0.0, and I encounter an issue when using uart21 (p2.07–p2.08). If RTT is connected, UART transmission and reception both work normally. However, if RTT is not connected, data is often not received, even though I can see the correct RX waveform on an oscilloscope. If the nRF54L10 sends data and the slave device responds immediately, the nRF54L10 can receive the data. But if the nRF54L10 sends data and the slave device responds after a delay of about 10ms, the nRF54L10 cannot receive the data.

[Kazi Afroza Sultana]

Hello,

I can see a previous case (9) [nrf54L15-PDK] Trying to use pin2.07 & pin2.08 with UARTE instance uart21, but get framing error - Nordic Q&A - Nordic DevZone - Nordic DevZone similar to yours. 

You can try to call "NRF_POWER->TASKS_LOWPWR = 1;" when UART peripheral is no longer in use.