Actual UART support and performance on Banana Pi BPI-R4

[TSerge (Serge Torop)]

Hello, all,

I am trying to confirm the actual status of UART support on the Banana Pi BPI-R4.

Does the hardware UART work reliably and appear as a character device (e.g., /dev/uart*) under Armbian Linux?

Also, what is the maximum baud rate supported by this port?

– SY, Serge

[ericwoud (Eric W.)]

@TSerge

(e.g., /dev/uart*) under Armbian Linux?

The UART is about the first of the components of the board that gets support…

The armbian image is not an officiallly supported image I think.

[hyf (hyf9929)]

@TSerge

what is the maximum baud rate supported by this port?

MT7988A Datasheet (Wi-Fi 7 Generation Router) | MEDIATEK

I found information about the MT7988 online. It states that the Baud rate is programmable from 300 bps to 3 Mbps.

[kvic]

@TSerge

Does the hardware UART work reliably and appear as a character device (e.g., /dev/uart*) under Armbian Linux?

No reason the “UART/debug port” isn’t supported by Armbian. You can ask on Armiban forum for clarity.

Note that there are two additional UART ports on MT7988A. Personally, never looked at how well they’re supported.

Btw, to get excellent hardware support of all features in BPI-R4/MT7988A, you might want to run a community build of MediaTek’s latest official firmware. Last check in December 2025, there is at least one such build available from OpenWrt forum.