Bricked Redmi Ax6000 Openwrt

Installing and Using OpenWrt
22

no, if UART is dead, then it's hard bricked, and you'll need to desolder, it that's even doable.
as long as UART's working, you can bring it back to life.

1 Like
23

Since I am new to UART and this will be my first time using it. I need some help selecting the right USB to TTL

so I heard the common ones are CP2102 and FT232, So I selected this one:

https://www.amazon.com/HiLetgo-CP2102-Converter-Adapter-Downloader/dp/B00LODGRV8/

I will be using a paperclip to connect to the pins and my router is 3.3V.

Now some questions:

  1. Is the Cp2102 that I chose from Amazon suitable for my router ?

  2. Do I need to use the power adapter during UART ?

  3. What programs do you recommend for this? I also have ubuntu wsl, Putty and Termius premium, and a raspberry pi 4

Thanks.

24

CP2102 is just fine, it needs to support 3.3v, which the one you pickled does.

you only need the power adapter of the router, and you never connect the VCC pin.

Putty works for Windows, that's what I usually use.

seems you should be able to use your RPi4 as USB TTL too.

1 Like
25

This is what my termius serial client looks like:

image
image1601×930 47.5 KB

and i assume 115200 means Baud Rate, 8N1 means: Data Bits: 8, No Parity, and Stop bits 1.

26

Using RPI4 as a usb ttl how does it work? Just connect jumper cables to the selected GPIO pins?

27

never tried it, don't own one, but I'd say yes.

28

This is what the gpio layout of the Pi 4B looks like:

VCC: Not using X

Since RX and TX are needed but not specifically mentioned, I assume they are related to ports GPIO 14 and 15 and for GND, I assume its full form is ground. which means any grounded GPIO pins can be used correct?

and for RX and TX, I hear sometimes peoples connect it by RX <--> TX, and TX <--> RX instead of connecting is serially like RX <--> RX and TX <--> TX. Which method I should be using?

Thanks

29

yes it's GPIO 14 & 15, plus one of the ground pins.

Tx <> Rx / Tx <> Tx, just try both, unless it's dead, then nothing will work.

1 Like
30

From my tries and pictures of the current status of the router do you think the UART and Everything is possibly dead and hardbricked?

31

like I said, if UART's dead, then it'll be really hard to get it back,

32

Anyway, I will go for the UART.

I have just installed PuTTY on my Raspberry Pi. I assume these configurations are correct:

image
image692×622 34.4 KB

If I am using a Raspberry Pi 4 as a serial adapter, would I only need jumper cables and paperclips? Then, I would connect RX to RX, TX to TX, and GND to GND between the GPIO pins and the router. VCC would not be required in this setup.

Thanks.

33

probably, you own the hw combo, I don't.

or reverse, like i said.

yes

connecting VCC could fry your device, unless it's already dead.

1 Like
34

and for jumper cables I will buy this one correct?

35

40 pack sounds slightly overkill, but yes.

1 Like
36

That's what they only have, I could order online but it would cost more and would take ages to come. That's why I will go to the store physically and buy it by myself.

37

got no old PC case, those kind of wires are used there, at least one end of the cable would have the connector..

1 Like
38

if the output of the serial is garbled even after mixing rx and tx, Then it is safe to assume that the UART is dead right?

39

no, then i'd say it's the wrong speed, bad GND connection, or both.

1 Like
40

Ok so dead UART means completely disconnected and it wouldn't even show up or connect?

41

dead would be ... dead :wink:

like Polly in Monty Python kind of dead.

1 Like