Hardware Limitations for Using P0.27 as UART RX on DWM3001CDK

[oussema ben khedher]

Hi,

I'm working with the DWM3001CDK (nRF52833 + DW3110) and currently using SPI to interface with the DW3110 for UWB communication.

I'm trying to use a second UART to communicate with another external MCU, and I wanted to repurpose P0.27 as UART RX. However, it doesn't seem to work properly, while P0.07 works fine.

I found that P0.27 is connected to the DW3110's IRQ line, which is used for UWB interrupt signaling. I understand this might conflict with UART usage, but I wanted to ask:

My Questions:

1. Is there a hardware limitation that prevents using P0.27 as UART RX?

2. Is the IRQ pin of the DW3110 actively driving P0.27, even if I don't explicitly enable IRQ in software?

3. Can you confirm if P0.27 is strictly reserved and should not be repurposed in this context?