Support for TL-WR840N(ES) Ver 5.0 (EU)

Yes
That 9pin connector (DB9) looks like RS232, your router/modem typically uses 3.3V UART, they are different.

https://www.sparkfun.com/tutorials/215

I bought "Prolific USB-to-serial" USB\VID_067B&PID_2303&REV_0400
@mbo2o thanks for telling me I seem to have bought the wrong adapter

I may now try get a RS232=>UART adapter

or USB=>UART adaptor

https://openwrt.org/docs/techref/hardware/port.serial.cables?s[]=ftdi

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@mbo2o I have a doubt about this, my adapter seems to have PL-2303 XHD chip. is there any chance to disassemble it and use it as a USB=>UART adaptor instead of rs232?Untitled2

Probably, but I personally wouldn't do that to a working adapter that I can use for something else.
Also it maybe configured as 5V UART instead of 3.3V which is what I think you need so it still may not work.

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Hi, @pradorocchi

Basic - Working fine
Full - Reset settings on reboot

Need your help - Basic is fine for me, just need ppp to be added in it.

Thanks in advance

Hey @pradorocchi great job - could you post your .config so I can follow and try to build it on my buildroot? thanks.

Descarga el firmware TL-WR840N(ES)_V5_170503 de la pĆ”gina de TP-Link de EspaƱa, Usa un editor hexadecimal y llena de 00 (zeros) desde x0 hasta x1ffff, luego borra los bytes desde x2000 hasta x201ff, guarda los cambios. El archivo te debe quedar de 4,063,232 bytes (el firmware original tiene 4,063,744 bytes). Usa el procedimiento de recuperaciĆ³n de firmware de TP-Link con el TFTPD. Si quieres te puedo mandar por correo el firmware ya modificado.

Please always provide an english translation, so that everybody around the world can participate without having to use a translator.

Translation - Download the TP-Link firmware from the spain website, TL-WR840N(ES)_V5_170503, use a hex editor and zero out from x0 to x1ffff, then delete byets from x2000 to x201ff, save changes. The file should be 4,063,232 bytes (while the original has 4,063,744 bytes. Use the recovery procedure for TFTP to flash this modified firmware. He can send (@albertoflg) the modified firmware to carlos16 or whomever, I reckon.

Have a great day everyone.

Hola Alberto, al poco tiempo de bloquear mi router pude recuperarlo con una sugerencia en este foro y fue de la siguiente manera:

  1. Copiar el firmware stock a la carpeta /tmp en LEDE
  2. Eliminar la parte del cargador de arranque de la imagen con el comando dd
    2.1. # cd /tmp
    2.2. # dd if=originalfw.bin of=originalfw_striped.bin skip=257 bs=512
    2.3. # sysupgrade originalfw_striped.bin
  3. Reiniciar

Esa fue la manera como pude restaurarlo a su firmware original ya que con LEDE no funciona el Wireless.

Saludos

Please always provide an english translation, so that everybody around the world can participate without having to use a translator.

Good morning, Colleagues, I apologize for not having translated my comment but when I was doing it I was without Internet.

After a short time of blocking my router I was able to recover it with some suggestions in this forum and it was as follows:

The first thing I did was to install the Recovery by TFTP, which is named tp_recovery.bin

https://drive.google.com/drive/folders/1X5fYd4_ZXvp4e5EiWXtBqBKXHXz7Hz4V?usp=sharing

To return it to the stock firmware the following:

  1. Copy the stock firmware to the /tmp folder in LEDE
  2. Remove the boot loader part of the image with the dd command
    2.1. # cd /tmp
    2.2. # dd if=originalfw.bin of=originalfw_striped.bin skip=257 bs=512
    2.3. # sysupgrade originalfw_striped.bin
  3. Restart

That was the way I could restore it to its original firmware because the Wireless does not work with LEDE.

Regards.

Download firmware TL-WR840N(ES)_V5_170503 from Spain TP-Link website, use a hex editor to fill zeros (00) from x0 to x1ffff, next delete bytes from x2000 to x201ff, save changes in a new file or overwrite, as you wish. The new bin file must have 4,063,232 bytes (original firmware is 4,063,744 bytes long). Use the TP-Link recovery procedure using TFTPD. If you wish I can send you the modified firmware. This was made because a bricked WR840N v5 was impossible to recover with the original downloaded firmware and OpenWRT/LEDE fimware was unsuccessful too. In this fĆ³rum I found a posted OpenWRT/LEDE firmware without LUCI that successfully recovered the router, so I analized the file and made the procedure described here to put the original TP-Link firmware in the router and unbrick it.

Hi mate
Have you bought a new one adapter for this? or It worked using the usb to rs232 (DB9) adapter?
Thanks

You mustn't use a DB9 style serial adaptor, its voltage levels (+/- 25 volts) would permanently destroy the hardware; most routers require 3.3 volts based serial consoles instead.

How to edit bin files.

I want to change default password in firmware image

Hi, sorry for my delay.. (realife problems took me out of scene. Now iĀ“m back)

If iĀ“m not wrong, I compiled the .config inside the image. Please verify inside /proc if itĀ“s there.

Hi,
you post was months ago, sorry, I was out of scene because realife problems.

Do you still need my help?

This router is super easy to unbrick.

Simply TFTP the original TP link firmware downloaded from the TP link site.
And it will be unbriked.