Hi,
I'm trying to de-brick TP-LINK WR841ND 8.1 . On cable Nokia DKU-5 I'm able to type/send data, but there are too many errors during transfer, whenever I switch data to anything else then 115200 speed, I get garbage only.
When I use cable CP2102 USB 2.0 to TTL UART cable (http://www.aliexpress.com/item/CP2102-U … .55.nsarG4) , on speed 128000 I'm getting 100% clear output but the console is read only.
I have tried 10 kOhm resistor between VCC and RX - no change. I was searching for R26 resistor, didn't found it. (should be anyway applicable for 8.1). I was changing PINs RX/TX if they are not switched - no change.

Any idea please what is wrong please ?

really, nobody ? ;-(

unclean ground.

I have it too. I have to be patient and patient and try again and try again and make sure it has a clean connection and it works.

Evidence of that was when I backed up my factory rom using md command in u-boot. It took a few goes to not have interference on the serial line.

pl2303's are fussy about the grounds. get a CP2102, or try your luck with a max232.

https://forum.openwrt.org/viewtopic.php?id=65786
Sorry for the cross post, but after getting mini_snmpd back into openwrt, I've got back to this task and it's going well. Show's you people can mess around with the serial port on a similar router. I'm a v9.2-VN spec (8mb rom)

Luke

oh if you can't write you do have to nuke r26 on the v9, i don't know about the v8. Just cleanly and carefully desolder it.

I RTFM before attaching a serial cable and soldered it before I ever wired up a serial connection.

Problem is it is V8 and not V9...unfortunately can't find r26 on the board. Anyone knows it's location ?

On v8 you don't need to remove it... only on v9.

Thank you - then tell me please why it doesn't work ;-(

- on Nokia DKU-5 - too many errors (I re-checked the contacts)
- CP2102 USB 2.0 cable - read-only, no errors however

Btw, I was using Nokia DKU-5 already to debrick WR741ND and with 10kOhm resistor all was fine but this is required for 741.

Anyones helps / ideas or even better experience with 841 debrick highly appreciated.

Hm, seems it is time to trow it away  ;-((

OK, so fixed....I start to ignore reading errors and simply followed debrick guide. Seems that only reading/displaying on the console is wrong, as everything went well (had to use Nikia DKU-5).

Look on the console output :

Autobnothng in 1 rebonds
#" Bootinf ilagd at 9f020000 ...

   Uncolprdsrinf Kdrndl Hmafe ... OK


Startinf kdrndl ...

[    0.000000] Linux version 4.1.23 (bkubesa@debian) (gcc version 5.3.0 (OpenWrt                                            GCC 5.3.0 r49395) ) #3 Thu Jun 30 21:35:52 UTC 2016
[    0.000000] bootconsole [early0] enabled
[    0.000000] CPU0 revision is: 0001974c (MIPS 74Kc)
[    0.000000] SoC: Atheros AR9341 rev 1
[    0.000000] Determined physical RAM map:
[    0.000000]  memory: 02000000 @ 00000000 (usable)
[    0.000000] Initrd not found or empty - disabling initrd
[    0.000000] Zone ranges:
[    0.000000]   Normal   [mem 0x0000000000000000-0x0000000001ffffff]
.....cut.......

Any idea why this is happening ? Booting log is already without error but console is bad.