Help finding rx/tx on the Somfy gateway for reversing
Trying to reverse engineer an old Overkiz / Somfy TaHoma gateway (Overkiz_KB1) to bypass the increasingly broken cloud/app ecosystem and hopefully expose local control for Home Assistant.
Board is based around an Atmel ATSAM9G20 ARM SoC and appears to run embedded Linux. Ethernet comes up, device gets DHCP, but most ports are filtered except 53/tcp. The system is bricket because the existing TaHoma Classic ecosystem seems half-dead and provisioning/login flows are unreliable.
Trying to
- re-use the gateway as a local bridge into Home Assistant
- gain UART / serial console access
- inspect boot logs / init
- dump firmware if needed
- look for hidden local APIs/services
I’ve already identified the following components:
- ATSAM9G20 CPU
- NAND flash
- probable RF daughterboard area
- several test pads / pogo pads
- labels like “GTO” / “GTL” near status LEDs but I don't know what they mean
I suspect there’s a serial debug console somewhere but I’m trying to identify the correct TX/RX/GND pads safely before attaching a USB TTL adapter.
Does anyone familiar with older Atmel embedded Linux boards or Overkiz hardware recognize likely UART/debug locations from these photos?
would love some pointers!