Howdy,

Sometime ago before I recently became a amateur radio operator I had a WRT54G. I tried to flash it to DDWRT, but was never successful. I believe that I bricked the unit that I have. I was wondering if anyone has had experience with un-bricking them?

Thanks,

KK4URZ

Take a look at the posts located here: http://www.hsmm-mesh.org/hsmm-mesh-forums/view-postlist/forum-3-firmware/topic-566-wrt54g-firmware-crash.html

Chances are you did not corrupt the bootloader, as that is hard to do. The easier of the three (CFE, NVRAM, and Kernel) is to corrupt the nvram on the flash chip. A simple shorting of the two respective pins and TFTPing the stock linksys firmware back to the device should solve your problems. Also, remember to leave the device powered on for ~5 minutes after flashing to allow it to fully boot up and do it's thing. Only use JTAG if all else fails.

I tried to short the pins, and will have to try it again I didn't leave it up long enough. Will it ping right away or after the 5 minutes?

I tired a lot of these some months back but never  had a real reason to get this up and going now I do :)

Thanks again.

It should ping right away. Make sure to set your computer as a static IP address and it is in the 192.168.1.x/24 address range. I normally short pins now instead of JTAG due to it being much faster than a 2-hour load. I am by no means condemning the JTAG route. If you do go that route, instead of flashing the flash chip using a JTAG cable, just erase the nvram and kernel, and then the router will automatically go into TFTP mode for flashing upon it's next power cycle.

Then I'd go with the JTAG route.

There are two I use. The first link is of the USB model (which is tons faster than the parallel port version), and the second one is the parallel port version I use if all else fails. Both gadgets do come with jumper cable.

http://www.diygadget.com/tiao-usb-multi-protocol-adapter-jtag-spi-i2c-serial.html

http://www.diygadget.com/jtag-cables/universal-jtag-adapter-for-routers-modem-fta-and-more.html

Documentation:
http://www.tiaowiki.com/w/Debrick_Wireless_Router_Using_TUMPA_and_zJTAG
http://www.tiaowiki.com/w/TIAO_USB_Multi_Protocol_Adapter_User%27s_Manual

As for the WRT54G2, at the time of writing this, the only supported devices are the WRT54G & WRT54GS v1-4 and WRT54GL's. If you can get it to work though, all the better!

I bought a JTAG setup a while back, to use on 3 bricked WRT54GS I had, and after they had been sitting on the shelf for several (5-6) months, they were mysteriously Un-Bricked..... I was able to go ahead and flash them to my surprise, and they now work great.

Never had to go the JTAG route...

You're not the first one to report that removing the power overnight or for a few days unbricked a router.  It's worth a try.

Actually I've upgraded to the correct sized helmet now. hah

So to update where I am on this. I bought a jtag cable, and removed the CFE, NVRAM etc per numberous instructions. Unless I'm missing something I can't get this to flash. The only thing I can think of is I have to edit the CFE with a mac address?

Owen - KK4URZ

You really should not have to erase the whole flash chip in order to get the router working. There is another parameter you can change in the CFE before flashing that back over. You want to enable boot_wait by changing the flag from a 0 to a 1. This will always allow you to easily tftp firmware to the router in case of any bad flash that may occur. Do not forget to put back on the router the same CFE you backed up. Without the CFE, the router is 100% useless.