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Topic: JTAG Problem - Please HELP! - Netgear WNR834Bv2 Bricked

The content of this topic has been archived on 13 Apr 2018. There are no obvious gaps in this topic, but there may still be some posts missing at the end.

Bricked the so I JTAG-ed it and ran the tool with option -probeonly
Ouptput:
Probing bus ... Done

Instruction Length set to 8

CPU Chip ID: 10010100011100000100000101111111 (9470417F)
*** Found a Broadcom BCM4704 KPBG Rev 9 CPU chip ***

- EJTAG IMPCODE ....... : 11111111111111111111111111111111 (FFFFFFFF)
- EJTAG Version ....... : Unknown (7 is a reserved value)
- EJTAG DMA Support ... : No
- EJTAG Implementation flags: R3k DINTsup ASID_8 ASID_6 MIPS16 NoDMA MIPS64

Issuing Processor / Peripheral Reset ... Done
Enabling Memory Writes ... Skipped
Halting Processor ... <Processor Entered Debug Mode!> ... Done
Clearing Watchdog ... ^C
===========================================

Since it was sitting on Clearing Wachdog for about 5 minutes I figured tool hung and I pressed Ctrl+C
Now when I try and run -probeonly again I get this:

============================================
C:\tjtagv2-1-4\tjtagv2-1-4\windows>tjtagv2.exe -probeonly

==========================================
EJTAG Debrick Utility v2.1.4-Tornado-MOD
==========================================

Probing bus ... Done

Instruction Length set to 5

CPU Chip ID: 01001010001110000010000010111111 (4A3820BF)
*** Unknown or NO CPU Chip ID Detected ***

*** Possible Causes:
1) Device is not Connected.
2) Device is not Powered On.
3) Improper JTAG Cable.
4) Unrecognized CPU Chip ID.

PLEASE HELP!!!
Note: Length was being set to 8 and now it's 5
Number under chip ID changed from (9470417F) to (4A3820BF)

(Last edited by storm_to on 4 Mar 2009, 16:19)

SOLVED after 2 days of debugging! It was a combination of bad ground (cold solder) and my JTAG cable (old printer cable) being too long. After resoldering ground and cutting the cable down to under 10 inches everything worked. I am now DE-BRICKED!

Had to do  "wholeflash" + "custom" + "NVRAM" + "CFE" + "TFTP Firmware.chk"

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