Linksys WRH54G

Manufacturer's site: http://support.linksys.com/en-us/support/routers/WRH54G

Front:

Note: This will void your warranty!

To remove the cover, remove the 4 feet and use a torx T-10 with hole or 2.5mm flathead to remove the screws.

Main PCB:

→ port.serial general information about the serial port, serial port cable, etc.

There is an unfilled five-pin header labeled JP1 which is a 3.3V TTL serial port. Experimentation with an oscilloscope indicates that it runs at 115200 8N1, but I'm waiting on the arrival of my serial adapter to verify. I believe this is the correct pinout, but I'm not certain about RxD and NC.