don't worry, can be fixed, tftp basically involves on running an exe that tries to provide a file to be download by the bootloader.
the usb-ttl adapter will allows you to have a telnet like access to the device, and while booting you can see the errors found (tipically bad magic number for firmware) and stop the booting process and run some commands to download a new firmware using tftp.
if you need I can help you with that, I've done some unbrick recoveries in the past when I was new on the topic.
start taking highres, hd pictures of the board and post them here, or link me to pictures of that device board.
I see something that could read J1 and a small triangle that could be the TP1. According to Heinz this would be order for the serial connection then?
JP1 - Tx (triangle?)
JP2 - Rx
JP3 - Gnd
JP4 - 3v3 - leave not connected?
For gnd you can test is using rhe continuity probes of a multimeter. That is the safest. Or with a very good zooming at both sides verify if the pin has connection to the ground of the board (usually has 4 lines like a cross connecting the circle and the rest of the board)
Then you don't need to connect 3.3v
And while booting your board you can connect either the tx/rx (if you dont know which one is which) one by one until receive text on the screen (that will be your tx board to rx ttl connection) and then use the other cable and try to send a key and see if you see it on the screen).
But sometimes you just find using google and someone else have already found the actual pinout for the board and you can skip those steps.
Then all depends if you use windows you can use putty or minicom/screen on linux... To connect to serial-ttl.
Yes. Seems to be right. Third one has that cross to gnd. And the last one has a bigger (for voltage) line.
If doesn't work you can just switch 1 and 2 snd retry.
I am still struggeling with what I would do with Putty (ind Windows)? I am using putty all the time to connect to my raspberry PIs, but what would be the settings for using it with a USB TTL cable and how do I transfer the firmware? This process here: https://www.youtube.com/watch?v=ZW5fpOWpI0I does not work with teh RE450 (this was mentioned in the OpenWRT forum several times).
VERY HELPFUL! I now understand, what you meant with the PCB lines. Will solder in pins and test the TTL connection via putty. Maybe no today, but sometime next week or weekend. Need to work now. Will keep you posted, how far I get with the serial connection! Greetings to Buenos Aires.
Could not resists and tried it. When I power on the RE450 all blue LEDs flash briefly once. Then they are dar. I started the unit with the reset button pressed, without the button pressed, with the reset button pressed the moment the blue LEDs flashed: no luck. I swapped the Rx Tx lines. I used Putty with the COM port selected that the USB TTL was attached to. I am unable to enter this "magic mode", where the device is looking for the firmware. I am affraid that the RE450 does not behave like the other TP link products: https://www.tp-link.com/fr-be/support/faq/844/
a year passed and I have not managed to get this to work. It would be a shame to throw this device away without making another attempt to reinstall the firmware. In your post you suggested that I needed to shorten two areas. On this page https://openwrt.org/toh/tp-link/re450 however (image section) it says: TP-Link RE450 v2 []the one I have] needs unmounted R64 & R69 0201 resistors/jumpers". Now I am confused. Does that mean I should not mount (solder) these R64 and R69, or does it mean I need to undo it after the flashing process?
Would it be possible that you help me with step by step instructions to do the full flashing process? I have flashed all kinds of devices before (ESP32, ESP8266, other MCUs), but I am struggeling with this device and I don't want to destroy it completely.
