Pixhawk 6X - UART5 Buffer Size


I was checking the nuttx-config/nsh/defconfig file for fmu-v6x and I had a question.

Is there any special reason that UART5 RX Buffer Size is not configured?

At first I thought it was because UART5 supports RX DMA.
However, UART7 and USART3 that also support DMA had RX Buffer Size configured.