Enable UART2 as normal serial port on Rock 3A

yftoh · February 28, 2022, 7:30am

Hi, I have an existing hardware (PCB) that uses the pins 8&10 on the GPIO header as UART port. It seems like it is a debug port by default. Can I disable the debug console and use it as a normal UART / serial port ? It seems like there is no overlay is provided for uart2 ?

yftoh · February 28, 2022, 3:45pm

I have tried changing the boot parameter by removing the console=/dev/ttyFIQ0… from the /boot/extlinux/extlinux.conf but it still appears in the boot param (cat /proc/cmdline still contains console=ttyFIQ0,1500000).
What is the correct way to modify the kernel boot parameter? I am not familiar with extlinux bootloader.

vanthome · March 3, 2022, 7:35pm

same issue here. I need UART2. How to enable it?

meteor_liu · March 4, 2022, 10:41am

I have the same problem

jack · March 4, 2022, 12:49pm

It’s fixed now, update to the latest kernel and enable the dtbo.

yftoh · March 4, 2022, 12:52pm

I have contacted the support and they released the fix a couple of days ago. Using the new image, add rk3568-uart2-m0 to the overlays in /boot/uEnv.txt, and then it will appear as /dev/ttyS2. I have tested and it works well. Thanks the support team for the quick fix!