OpenWrt/LEDE Project

  • Status Unconfirmed
  • Percent Complete
  • Task Type Bug Report
  • Category Base system
  • Assigned To No-one
  • Operating System All
  • Severity Critical
  • Priority Very Low
  • Reported Version Trunk
  • Due in Version Undecided
  • Due Date Undecided
  • Private
Attached to Project: OpenWrt/LEDE Project
Opened by Reiner Otto - 23.10.2020

FS#3402 - RUT955: Seriously broken

RS485 and RS232 (DB9) unusable on my recent RUT955, batch 84.
I want to use RS485 (in worst case, RS232) for modbus comms.

However, my custom built image basically works, incl. mqtt, mwan3, LTE (EC25) etc.
The firmware from TELTONIKA runs without problems.
For strange boot log, pls refere to


Project Manager
Daniel Golle commented on 31.10.2020 23:35

RS-232 is connected via USB needs driver and is available on /dev/ttyACM0.
There is also nothing 'seriously broken' about using the kernel upstream driver for what they call 'ar934x-hs-uart' in Teltonika's firmware. Take a look at the driver and realize that it's basically the same UART as used in earlier Atheros SoCs, just that it wasn't initialized by the bootloader. There is no need to duplicate tons of code for that.

What exactly doesn't work? (I'm sitting next to the device and it does work for me)


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