E3000 Bricked - Need Serial or Jtag? [Split]

Post new topic   Reply to topic    DD-WRT Forum Forum Index -> Broadcom SoC based Hardware
Author Message
orolim
DD-WRT Novice


Joined: 30 Dec 2011
Posts: 2

PostPosted: Fri Dec 30, 2011 14:21    Post subject: Linksys E3000 brick - Serial recovery failed Reply with quote
Hi everyone,
I'm new on this forum and I need some help with my E3000 router which seems to be bricked. I updated the firmware from Cisco website as per there instructions. After approx. 2 weeks starts to get stuck and I have to reset the router twice a day. Finally, all the lights are not lit, only the power light is flashing. I spent a week reading all your wiki and start to debrick following the Peacock Thread. Because the LAN ports are dead I moved on to serial recovery.

1. I found a DKU-5 Nokia cable (USB-UART Tx line) with OTI6858 chipset, found the drivers and install it (PC found on COM6). Dismantle the USB and found the Tx, Rx and GND on the board (I was surprised that everything was marked).
2. Solder the 3 wires to the router GND (router) to GND, RX (router) to Tx and Tx (router) to Rx (USB adapter). I used the internal 5 pin serial port.
3. Open Putty, configured COM6, 115200, 8, 1, none, none.
4. Start router and very fast press Ctrl-C. Done this plenty of times and I'm sure is fast enough. The message I get is "Error writing to serial device".
5. I measured the voltage between GND and Tx and Rx. All values are equal approx. 3.25 V.

I used a laptop computer with Win7 and Putty.

Now, I'm not sure if I have to try with a CA-42 cable or i have to move on to JTAG. If I have to use JTAG, can anyone tell me if I can use a simple parallel cable (home made as per wiki) or I need a buffered JTAG adapter? Also, the last version of JTAG knows the chipset for E3000 (BCM4718)?

Thanks a lot for your time and help.
Sponsor
barryware
DD-WRT Guru


Joined: 26 Jan 2008
Posts: 13049
Location: Behind The Reset Button

PostPosted: Fri Dec 30, 2011 19:18    Post subject: Reply with quote
I have fixed many E3000's (& 610 V2's).

1st, it is not normal to have to reboot the router twice a day. I would suspect failing hardware. A power supply failure is very common. It may be just weak and not totally fubar. Check the PS before you do anything else.

2nd, assuming that the hardware is intact, no serial output is getting more common with this router. I have not been able to determine the cause.

Lets again assume that you have tested your serial adapter by connecting the tx to the rx of the adapter and verifying that your keystrokes are echo'd in the terminal.

if the hardware is intact, and your adapter is working properly, and you still have no serial output, then you will need jtag to erase nvram "only". Once nvram is erased, then serial should now operate properly.

The problem with the router is that linksys has disabled the jtag circuit on the pcb. You need to bridge 5 pads on the pcb to enable the circuit.

Check the convert you 610v2 to an e3000 thread:

http://www.dd-wrt.com/phpBB2/viewtopic.php?t=137565

About the 4th or 5th post, there is a pic of what needs bridging.

The newest jtag program does support both the router and an unbuffered cable. You will need to contact Tornado directly to obtain the utility.

good luck..

_________________
[Moderator Deleted] Shocked
orolim
DD-WRT Novice


Joined: 30 Dec 2011
Posts: 2

PostPosted: Sun Jan 01, 2012 8:44    Post subject: Reply with quote
Thanks a lot for your fast reply. I will contact Tornado for JTAG and I will post the status. I changed the PS before the router got bricked because I experience same problem with my old WRT300N, 2 years ago. That time was the power supply faulty.
Display posts from previous:    Page 1 of 1
Post new topic   Reply to topic    DD-WRT Forum Forum Index -> Broadcom SoC based Hardware All times are GMT

Navigation

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You can attach files in this forum
You can download files in this forum