On Mon, Aug 22, 2016 at 10:30:42PM +0200, Jochen Demmer wrote: > Thank you everybody, > > I've been trying for 2 hours straight to unbrick via serial, using a > prolific pl2303 adapter but without success. > > I tried screen, picocom and minicom. I tried Apple's terminal emulator and > iTerm2. Got me a Mac and then Linux. Desperate as I am also connected > another C7. > I tried like a whole bunch of different settings but no matter what, I get > gibberish characters. > > ./picocom /dev/ttyUSB0 -b 115200 -y n -d 8 -p 1 > > These are the settings I think they should be set to, but it just won't > work. > Actually only RX and TX are connected, because when I connect GND the serial > connection freezes and let USB subsystem crash. Connecting VCC doesn't seem > like a good idea, too.
NEVER connect the VCC of the board to a USB-to-serial adapter! > Any hints? If connecting the ground causes problems like you described, probably the device is really far-off the ground-level compared to the GND of the USB port, so when connected you got a non-neglectible current flowing and supposedly frying the USB-to-serial dongle. This is often caused by crappy power supplies, so if you got a laptop, try running it from battery and have the GND connected, that may fix it. > > Jochen > > On 2016-08-22 11:29, Kevin Darbyshire-Bryant wrote: > > On 20/08/16 22:35, Jochen Demmer wrote: > > > Hi, > > > > > > yesterday I bricked an Archer C7 v2 by installing some homebrew > > > (buildroot) lede firmware. > > > > I've only once encountered an issue which I can only assume was a bad > > flash. It's a few months ago so memory is vague. The serial console > > was booting linux but it was reporting something about corrupt > > filesystem markers & couldn't mount filesystems. Even using the tftp > > recovery method to re-install factory firmware didn't work...the > > factory firmware was having similar partition table issues. I > > genuinely thought I'd bricked it and purchased a replacement that very > > morning...with the replacement up & running I then set about seeing > > what I could do with the borked unit. Following the 'serial unbrick' > > instructions at https://wiki.openwrt.org/toh/tp-link/tl-wdr7500 I was > > able to unbrick it and it's been fine ever since... I'm using it as an > > additional access point for downstairs in the house, the new one is > > upstairs. > > > > > > Recovery using serial connection > > > > Connect to your router via serial, power it up, then type "tpl" until > > the boot process is halted and you should be at the console. Set up a > > TFTP server with your firmware at 192.168.1.100, then run the > > following commands (for v2 only): > > > > tftp 0x81000000 [name of your firmware file].bin > > erase 0x9f020000 +f80000 > > cp.b 0x81000000 0x9f020000 0xf80000 > > reset > > > > > > I'm convinced it was the 'erase' command that cleared out some bad > > data in the flash. Like I said, the unit has been absolutely rock > > solid ever since. > > > > Kevin > > > > > > > > _______________________________________________ > > Lede-dev mailing list > > Lede-dev@lists.infradead.org > > http://lists.infradead.org/mailman/listinfo/lede-dev > > _______________________________________________ > Lede-dev mailing list > Lede-dev@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/lede-dev _______________________________________________ Lede-dev mailing list Lede-dev@lists.infradead.org http://lists.infradead.org/mailman/listinfo/lede-dev
