Router recovery via serial pin with second router

I want to recover my router. I have read a lot about the serial method. I am still missing the usb serial adapter cable. Can I use a 2nd router and connect the pins direct? Or is this a stupid idea.

My plan:

  • connect the pins direct
  • use the secondary router for the serial console

Yes but never try it myself
https://wiki.openwrt.org/doc/hardware/port.serial#use_another_openwrt_router_as_a_console

I wouldn't have guessed it was possible...

Since you can get an adapter for $8-10 or less... probably worth getting a regular one.. Depends on your desperation level, I guess....

Don't forget to cross TX and RX...:slight_smile:

Hm, it will not work. Or?

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▒a▒ ▒ ▒x▒0▒0▒0▒3▒
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▒2▒ ▒B▒
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▒l▒s▒:▒1▒ ▒B▒
▒▒▒ ▒a▒n▒n▒ ▒▒ ▒ ▒C▒e▒W▒A▒ ▒o▒u▒e▒n▒t▒f▒u▒d▒!▒!▒
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Looks like "ground" is not making a proper connection :wink:

1 Like

I was thinking the same thing. But I've been studying the thing for several hours.

The log looks similar to the one described here.

The broken Router is a TP-Link Archer C7 and a TP-Link WR840 v3 is used for serial access.
I connected TX/RX (crossed) and the GND pins.

Is your second router using the same serial protocols as the C7? If they aren't the same, you'll get garbage.. Same if you don't have a good ground. If your can, find out what terminal settings they use by default, and if they can be changed to match. Any one being off, and you'll get garbage or nothing...

Not sure if this could be your problem, but I had one C7 once I couldnt talk to till I pulled up one of the lines, with an unusually low pull up resistor, look at the levels for that. Was almost like they put a pull down in there to keep people from using the port.