Uart problem

[shum-elli]

I want to enable a uart on orangepi3b sbc.
I have met some problems. It seems like that i can't enable uart7 by overlays.
I use this img Armbian-unofficial_24.2.0-trunk_Orangepi3b_jammy_edge_6.6.4_gnome_desktop.img
Everything include 3.5mm mic & sound work right.
I have tested uart2 on sbc, it can works right, and i can see log in dmesg. I want to know how it works, it is configed when kernel is build?
Could you give me some advice to solve the uart problem

[defencedog]

Can you shared some pics of output & your GPIO layout setup? Please include what you intend to do

AS per official documentattion there is no uart2 http://www.orangepi.org/orangepiwiki/index.php/Orange_Pi_3B#40pin_UART_test

As can be seen from the table below, the uart available for Orange Pi 3B is uart3, uart7, and uart9. There are three sets of uart bus

[shum-elli]

this is uart2
I want to use overlay to make it more regular,I clone armbian/build & build the system locally
I use rockchip-6.12 kernel, and add a file to enable uart3 ， I successfully get the img,and see it dtbo file in my /boot/dtb/rockchip/overlay volume
rockchip-rk3566-uart3.zip
then i add it in amrbianEnv.txt file, reboot & do not see the uart3 log
Now i use a vulgar way to solve it, I burn the img,and use dtc command to convert dtb to dts, and make uart3 status"okay",then convert dts to overwrite original dtb. Now it works right. I want to know why overlay not effect.
If you need ,i can provide my DIY image.

[shum-elli]

And uart7 is confict with wifi module, enable it will let wifi model down.
My board is v1.1,and lan can't get ip address,so i do not test uart7

[defencedog]

@shum-elli 1st congrats on your effort, 2nd do please upload .img file along with kernel headers .deb file. I will add it in my repo.

Regarding your problem. Armbian u-boot may be thinking that your SBC is v2.1. In /boot/armbianEnv.txt can you manually add fdtfile=rockchip/rk3566-orangepi-3b-v1.1.dtb entry

This is my file contents see the u-boot auto-determines SBC revision. For 1.1 it may not work

verbosity=4
bootlogo=true
console=both
extraargs=cma=256M
overlay_prefix=rk35xx
#overlays=panthor-gpu
rootdev=UUID=62f0e84d-5e0b-4889-9d4d-69d89d79b335
rootfstype=ext4
usbstoragequirks=0x2537:0x1066:u,0x2537:0x1068:u