Can the OPI5 be Configured to Run LCNC?

What does dtb stand for?

Also, as I bring this together, should I document the effort here, or a separate build thread? I'd like to lay down a clean trail of breadcrumbs that the next person can pick up.

Device Tree Binary, you'll find it somewhere in /boot/dtb
For me it's all ok, but it might be easier to find and to follow when you start a new thread.

Royka (or any other..),
do you know why serials are not working?
Could be disabled in configuration?
armbian-config setting has no "Hardware" configuration, I checked again in the kernel config but I did not found a specific "enable" for serial.
ClassicLadder search for ttyS0, 1,2,3, USB0, USB1
I found that I have a ttyS9, I don't know why.. in case, how to change the list in ClassicLadder?

Now I have OPI5 working fine, driver for GPIO, today I also enabled my custom HMI based on qtpyvcp.. last step is the modbus for spindle and additional I/O I already have, than I replace RPI4

I tried to add "overlays=uart0-m2 uart1-m1 uart3-m0 uart4-m0" as explained in the manual, but nothing..
 

Perhaps you don't have the overlay files in /boot/dtb/rockchip/overlay.
You could download them (save raw) from:
github.com/orangepi-xunlong/linux-orange...dts/rockchip/overlay

Then to compile for example:
dtc -I dts -O dtb -o orangepi-5-uart0.dtbo rk3588-uart0-m2.dts

Place the dtbo file in /boot/dtb/rockchip/overlay/
In armbianEnv.txt
overlay_prefix=orangepi-5
overlays= uart0

The downside to do it this way is when you install/update a new dtb the added overlays will get deleted. There is also an option to put it in something like user-overlays which get not deleted, but I haven't tried that yet.

Would be nice if you would share your driver. About your previous post I read the step rate should be divided by 2 because it's one for up and one for down.

Thanks, I will share of course.. I'm just waiting after a real test with hardware, maybe I have something to adjust and I have to re-post the file updated. Give me few days I will attach it! 

I checked and now the serial works perfectly !!
I'm now designing the interface board and finally I will test on CNC.

Last question: I can work with ttyS0 or ttyS1 so in principle I'm fine.. but.. there is a potential debug UART on OPI5 (3 pins separated and close to GPIOs).. why I can't do the same as other UARTs? In the repo you posted above, I can't find dts for this port, in the manual is reported as ttyUSB0, I found some info in the web and based on them, it seems to be ttyS2. 
 

Should I disable the console and then maybe I can access to it? (how?)
If it's an effort, I can deal with ttyS0, but using the debug port I can have 2 additional GPIOs for general purpose functions.. at the moment I don't need but designing the hardware interface I prefer to have the max flexibility.
 

Nice!
To disable the serial console I think adding the following line to armbianEnv.txt should work:
console=display
There is no overlay file for it needed I guess because it's enabled by default in the dtb.

Yes, I disabled the console (at least the command console=ttyS2 disappeared) but unfortunately it doesn't help to get the port available.. 
Strange.. if I try to create manually the dts like others based on UART2? The problem is that ttyS2 is not present in dev folder
 

I see it's already in use in:
github.com/armbian/linux-rockchip/blob/r...ip/rk3588-linux.dtsi

When I enable this overlay I can see ttyS2, could you test this one?
 

I placed the file into /boot/dtb/rockchip/overlay/ folder, as others files and if I add uart2 in the overlay command into
ArmbianEnv.txt file, it doesn't boot.. doesn't startup.
I tried to add the file and remove the uart2 name in the ArmbianEnv.txt file and the serial is not existing..
What I did wrong?
The file it seems in the folder above in the repo, should I place it in /boot/dtb/rockchip/ folder?