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by anonymous
I built a custom firmware image for the RUT955, based on official, latest openwrt.

Basically works, incl. EC25. But now I need to use RS485 and RS232 for modbus-serial.

Any idea, which of the following devices might be the RS485, and the RS232 (DB 9) ?

console, tty, ttyS0, ttyATH1, ttyUSB0, ttyUSB1, ttyUSB2, ttyUSB3 ?

In case, I would build an image using your SDK, which device would be RS485, RS232 then ?

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by anonymous


simple command ls -l in /dev folder should output all possible communication interfaces. So in your case, RS232 > /dev/ttyACM0 and RS485 > /dev/ttyATH0


by anonymous
Thanx for answering. Actually, I do _NOT_ have neither /dev/ttyACM0 nor /dev/ttyATH0. Only the ones mentioned. May be, because of my custom .config . So I will build an unmodified, official openwrt image for checking again. Thanx for this info, anyway.  You know by chance, which kmods or drivers are required for /dev/ttyACM0 or /dev/ttyATH0 ?
by anonymous
If you're using an Official OpenWRT image I can't really tell what you should have instead of ACM0 and ATH0, as I do not run official OpenWRT on my testing devices.

But command should work the same way on Official firmware anyway, so once you've booted your router and if your firmware detects these serial devices - it should be found the same way.