Help with bricked RT-AC56U

[dzfacts]

The correct settings are 115200, 8N1.

Make sure you connect GND, TX and RX. Do not connect VCC.

One way to test the serial adapter itself is to unplug it from the router, connect the TX and RX pin of the TTL adapter together, and make sure that what you type in Putty echoes back on screen.

Another gotcha which I have been unable to explain: some adapters will prevent the router from booting if you turn the router on while it's already hooked to the serial adapter. The workaround is to turn the router on without the adapter connected to the router, and immediately after turning it on connect the pin headers to your serial adapter.

No success at all, even connecting the serial pins after of before, there is no cfe echo on terminal screen, my adapter echoes normally when I jump TX and RX together as if was a text editor, what I type ehoes on screen normally.

 

[RMerlin]

I assume you already tried swapping TX and RX.

If you are sure that your adapter is definitely designed for TTL signaling, then there's a good chance the router is totally dead, and won't even boot its CFE.

 

[dzfacts]

I'll try a different adapter when it arrives next week if it still fails, I'll have to buy a brand new router, how much do you think EA6200 is better or worse the my current ac56u?

 

[RMerlin]

I'll try a different adapter when it arrives next week if it still fails, I'll have to buy a brand new router, how much do you think EA6200 is better or worse the my current ac56u?

No idea, I'm not familiar with that model.