I also had the same idea but while removing the 32 chip I accidently removed this resistor "R74".
If someone could check the rating of this resistor then it will be easy for me.
So small resistor...
Hope you can fix it soon...
In indonesia,there is someone was success with the idea...
This is the link...
can someone please tell me what value Pull up resistor should I use on R74 .Chip pin 7
My multimeter says R74 has ~10 kOhm
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ok thank you
I install a Openwrt 18.06.0 and 18.06.1 from release files, but doesn't safe configuration after rebooting.
Anyone have the solution for this?
We had this problem of losing the previous configuration because the space left over to make the overlay filesystem shrank. So it seems that at least its first part gets overwritten, therefore making the data unreadable. The workaround is simple, saving the overlay partition (/overlay) before update (using tar or copy -aR to /tmp and scp to another system) and writing back the configuration files (mostly /etc/config) after update. It is more work than just running update, but if you configuration is complex it is worth it. Otherwise it may be simpler reconfiguring by hand after update.
S.
I'm trying to flash the tftp-recovery.bin file to my WR840N(ES) V5 router via tftp from a linux laptop. It takes the file from my laptop:
"in.tftpd[3487]: RRQ from 192.168.0.2 filename tp_recovery.bin"
flashes with green light for a second and then just reboots back to stock firmware 
.
Am I doing something wrong? I still don't have a USB=>Serial adapter (will buy one soon) to see what is wrong on the flashing process but when I try to flash sysupgrade.bin in web gui I get error: "71211"
I have strange terminal characters when I connect to serial port, any help?
That's usually a sign of bad GND connectivity.
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I tried resoldering and still get weird characters, looks like a boot process but the data is all weird chars. Now I'm hitting max post and max image attachment limits... 
Yes
That 9pin connector (DB9) looks like RS232, your router/modem typically uses 3.3V UART, they are different.
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
@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?
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 página de TP-Link de España, 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 recuperación de firmware de TP-Link con el TFTPD. Si quieres te puedo mandar por correo el firmware ya modificado.