Posted: Fri May 22, 2020 1:19 Post subject: Recent R7000 board revision - serial not working.
Wanted to see if anyone has had any problems getting the serial port on the R7000 working. I had one R7000 and bought another specifically for dd-wrt, so I had a working model while I played...
Have a current R7000 dd-wrt setup, so that works, but for the life of me I could not get the serial port to work. Its *possible* I damaged the board, however it definitely detects the serial port being present - just doesn't send anything. The USB dongle could be damaged (I will test/buy more), but I wondered if anyone could verify that there is not now some special trick or unlock for the serial port...
* GND, RX, TX
* GND, TX, RX
* (with sudo) screen, putty, plink, minicom (none of which appeared to see a terminal, or effect a change)
* socat (which didn't appear to log anything)
* several USB 3.0 ports on a recent linux laptop
* a USB port on a desktop windows
* Trying to hold down a key as I powered up the router with the serial attached.
I should note the R7000 had a known-bad version of firmware on it to begin with, when I upgraded it, things started to work fine again w. regard to being able to flash DD-WRT and OpenWRT.
I can provide board numbers etc. if anyone can confirm theirs , or has anything they could think of to try...
As I said, next steps for me would probably be to try to use the Serial Port to send a message to a device I can control like a Teensy or Raspberry Pi, but that's a bit more work that I was prepared for just trying an initial flash.
The images in all these guides are incorrect/misleading. I did find some images on the internet which show '1', '2' - GND, '3' - TX, '4' - RX, which seem to correspond better (my board has the pin placement in a completely different location/orientation that most of the online photos, but has the numbers 1 and 2 next to two of the pins). I will open my other router today and compare boards, I strongly suspect they are *different boards*.
Anyways, I get to about the equivalent of step 12 (I said I tried holding down keys, I suppose I could retry mashing ^C however other sources mentioned just triggering the port with any key...) and nothing happens.
I suppose I will retry that last step today, but otherwise not particularly helpful to me, sorry.
I will post back with images/more info when I have it.
Ok, so I verified that this is indeed a new version of the R7000 from 2018. I am not sure that the newer version identification info has been incorporated in FreshTomato or DD-WRT at present. The board_id information is DIFFERENT (see white labels on boards).
EDIT: I forwarded your original images to the developer to inquire if the 12/2018 revision has been properly added to the firmware support. I also contacted the FreshTomato dev team as well.
Also, to verify GND, you use the shield of the USB port or the actual GND from the power supply input jack. Then you verify the rest of the pins. At least that is how *I* do it.