Advice on opening Netgear R7800 case and using the serial console
The case bottom and cover are attached to each other pretty tightly, but the case can be opened once you figure out all necessary steps:
- The circuitboard is attached to a heatsink that is attached to the top cover. So the bottom panel (with sides) is the one to separate from the others. The heatsink is likely attached with a thermal paste or such (I never removed it).
- There are five screws (Torx T-10) on the bottom that need to be opened. One screw is visible and four are hidden inside the rubber feet (which are attached with adhesive tape)
- There are small clips on sides keeping the top cover tight even when the screws have been opened. These clips need to be carefully pronged open with a flat screwdriver or something.
- Additionally, there are fangs in the vertical backpanel protecting the connectors' holes (by preventing vertical lifting). In practice the front side can be lifted up first and the backside last by pulling forward so that the connectors slide free from the backpanel holes.
The serial header is right at the edge of the circuitboard, so it can be accessed even while the cover is attached to the circuitboard. I bended sideways the three needed pins (ground, rx, tx) that are luckily nearest to the circuitboard's edge, so that I could easily attach the serial cable. I left the farthest +3.3V pin untouched.
Using the markings in my USB-ttl converter, the pin order starting from the circuitboard's edge is: ground, rx, tx, +3.3V
Serial connection is the usual 115200,8,N,1
(The serial header can be seen through the left ventilation grill, so it might be possible to get access to it without by opening the case, by cutting a hole to the ventilation grill on the side panel.)
Bootlog starting with u-boot bootloader looks like this (LEDE master r3676-edda26dc4f):
https://gist.github.com/hnyman/8a68f6280ef5d267bba2ee80601fe8f0
EDIT:
I led the wire through side grill so that I access the serial header even when the cover is closed:
