Linksys WRT54G v5.0 & 5.1 & 6.0
From DD-WRT Wiki
 How To Flash
NOTE: During configuration or flashing a router, the only thing that should be hooked to the router is the computer through the ethernet cable, and power.
IN SPITE OF SOME OTHER INSTRUCTIONS ELSEWHERE, YOU REALLY NEED TO CREATE A CUSTOM VX Image for your router. If you don’t you will get a generic MAC address on your router and a generic MAC address will mean most ISP won’t let you connect to the Internet. Here is how to do it properly:
- Go to this thread and download the zipped files in GV5Flash.zip: http://www.dd-wrt.com/phpBB2/viewtopic.php?t=58231 (If you get a malware warning from your antivirus, ignore it. The file is clean and contains no malware).
- Read the peacock announcement found here: http://www.dd-wrt.com/phpBB2/viewtopic.php?t=51486
- Do a HARD reset on the router according to note 1 of the peacock announcement (30/30/30)
- Set a static IP on your computer to 192.168.1.7. Subnet mask should be 255.255.255.0.
- Connect the LAN cable from your computer to a LAN port of your router. Make sure your router is plugged in. Nothing should be connected to your computer or the router except the LAN cable between them. Turn your firewall and any wireless computer connections OFF.
- Unzip the file you downloaded in step one, and place it in a location you can easily find on your computer.
- Unzip the VXImgToolGui.zip file to the same folder as where you placed the other files you downloaded.
- Start VXImgToolGui.exe.
- Make sure the top button is on the left for WRT54G, not the right for WRT54GS.
- Put the MAC address from the bottom of your router in the box that says "Desired MAC" (Tip: You can also copy/paste the mac address from the Linksys Firmware Status\Local Network page)
- Click on the three dots next to "output image" and save the file as My54gImage.bin in the same folder as everything else is located.
- Power cycle the router (unplug the power from the router for 30 seconds and then plug it back in).
- Open your browser to 192.168.1.1 by putting that in the browser address window of your browser. You should open the linksys webgui and NOT a page that says Management Mode. If you see management mode, power cycle the router again.
- Enter "root" as the username and "admin" as the password.
- Go to Administration and Firmware Upgrade.
- Navigate to the folder that you are using, and select vxworks_prep_03.bin.
- Hit upgrade.
- Wait for FIVE FULL MINUTES. Go for a walk. Don't you TOUCH that router for FIVE MINUTES.
- When five full Earth minutes have passed, power cycle the router.
- Browse again to 192.168.1.1. If you get a blank window, clear your browser cache. NOW you should be in the MANAGEMENT MODE window.
- Select the My54gImage.bin file that you created. Hit Apply.
- Wait for the "Upgrade Success" message, and then WAIT FIVE FULL MINUTES again. Don't TOUCH your router.
- Start tftp.exe.
- Enter 192.168.1.1 as the address in the top box of tftp.exe.
- Leave the password blank.
- Select the 12548 Newd_Micro.bin firmware.
- Set retries to 99.
- Power cycle the router.
- Count to 2.
- Hit upgrade.
- When you get a success, wait FIVE FULL minutes.
- If you don't get success, repeat from steps 20(4) up to this one. If you still don't get success, clear your browser cache. Try using a different browser as well, to navigate to 192.168.1.1.
- When you can access the dd-wrt webgui using a browser at 192.168.1.1, power cycle the router.
- When you can again access the dd-wrt webgui using a browser at 192.168.1.1, do another HARD reset on the router.
- Reset your computer Ethernet connection to auto IP and auto DNS.
PROBLEM AND WORKAROUND TO AN INACCESSIBLE LINKSYS WRT54G V6.0 ROUTER--- may be good for V5 as well.
problem: power led blinking rapidly, wireless led is off, my PC is unable to get an ip address by way of DHCP.
steps taken to revive it with dd-wrt firmware:
- cycle power several times to see if it would change.... nothing
- as a result of this, I am unable to follow the steps outlined above concerning GV5Flash.zip.
- performed a 30-30-30 reset.
- DHCP now running, but now the router is in "management mode" at 192.168.1.1, my PC was issued 192.168.1.11.
- According to this wiki, it is advised to run "VXImgToolGui.exe" in order to save your MAC address so that's the first thing I did.
- Now, In management mode, I used the "vxworks_prep_03.bin" file to attempt to upgrade firmware since I am unable to do so logged in to router because the router wont boot. "Upgrade Success" at this point. The management mode page reloads again.
- I wait 5 full minutes (just in case) then, still in "management mode", I use the "My54gImage.bin" created with the ""VXImgToolGui.exe"" tool and run the upgrade again. "Upgrade Success".
- I wait 5 full minutes (just in case), then power cycle the router. I get the same "problem" as in the beginning only now I cant get back to management mode. I can still ping 192.168.1.1 though.
- At this point, I used "tftp.exe" (included in the GV5Flash.zip) and prepare that for flashing using the included "dd-wrt.v24-12548_NEWD_micro.bin" firmware.
- Now, give your PC a static ip address (192.168.1.x)
- Power cycle the router, and as you see your PC's LAN connection pop in, run the tftp.exe as prepared in the step above. Flash successful!
- Wait 5 minutes and during that time, look at your router. The power led will stop blinking and go steady and the wireless led will finally come ON.
- After all this, I am able to power cycle router and log in to dd-wrt!! At this point, I upgraded the firmware to the one I really wanted to use. Everything works. And my MAC address is retained. I hope this is helpful to anyone else reading this. ;-)....pcdocta
Interesting but non-sense notes:
I have a WRT54G v5, serial #CDFB (Neutered). Linksys firmware on it. First thing I noted, my router went in management mode everytime I hard-reset'd it. A supplementary powerycle was mandatory.
I followed the steps described in the wiki, but the TFTP steps didn't work at all. The modem was then stuck in management mode. I tried to use the management mode (white page) to upload vxworks_prep_03.bin and My54gImage.bin files again, the router reported me that it was a success but nothing changed.
After that when I tried TFTPing the 12548 Newd_Micro.bin firmware, it enabled the router to load in the normal mode instead if management mode. I booted the router many times and the results were the same: Boot without TFTP : goes in management mode. Boot with TFTP: goes in normal mode. The TFTP wasn't udating anything, it kind of "triggered" the normal menu. The TFTP program would show "Erasing...." for few seconds, then crash, and then the router would boot normally. Weird behavior...
From that point, I didn't know what to expect. So I reached and used the firmware upgrade menu of the linksys web gui to apply the Linksys standard firmware (found on Linksys website).
Then I tried again to follow the instructions in the wiki.
Got stuck at the same step. TFTP wasn't accepting the bin. The router kept returning my pings quickly (TTL=64).
But this time, the TFTP procedure didn't work to get access to the normal linksys gui.
Then I used the management mode gui to upload My54gImage.bin again. That time, my pings results were coming back with a TTL=100.
I don't know if it means something. But right after that the TFTP procedure worked 100%.
 Other Notes
Also see this page: Version 5 And 6 Router Information
There is good information at the scorpiontek site: http://www.scorpiontek.org/portal/content/view/27/36
A CFE compressor is available for the Gv5.0,5.1, and 6.0. It enables micro_plus to be put on the router. Click here.
Linux users: VXImgToolGui.exe successfully ran under Wine 1.3 (ubuntu default install) with no issues and tftp from repo used to upload image in BINARY MODE. No problems at all during install following steps above. WRT54G v6 running Firmware: DD-WRT v24-sp2 (10/10/09) micro directly, did _not_ use 12548 Newd_Micro.bin > upgrade, otherwise followed directions.