Трансфер на фирмвер преку TFTP би требало да го среди проблемот.
Ама прво погледај ги советите тука:
http://www.dd-wrt.com/wiki/index.php/Recover_from_a_Bad_FlashWRT54G/GL/GS
The LED display at the front of the router is the best way to determine what type of brick you have and its recovery method. You should at least check this to prevent unnecessarily opening the router.
When the web interface is no longer available, switch the router off first (remove the power jack) and remove all network cables from the equipment. After some seconds you restart the WRT54G. Now take note of the flashing LEDs.
The power LED flashes very fast. If it keeps on flashing longer than 2 minutes, without having lit up the other LED's, then a defective bootloader is present. However, if you can ping 192.168.1.1 (your router IP) you can try the TFTP recovery, otherwise you may need to open the router and use the JTAG recovery method below.
The power LED flashes very fast and after some seconds the DMZ LED lights up for approximately 5 seconds. In this case the Bootloader is intact and only the kernel (firmware) is defective. In this case you could possibly still recover with an ethernet cable if you reflash the firmware via TFTP (see TFTP below).
The power LED flashes very fast and after about 20 seconds it lights permanently, but the DMZ LED did not light up. In this case Bootloader and Kernel (firmware) are intact, only a wrong configuration from locked up the router. This can happen if a wrong or corrupt value exists in the NVRAM. Here simply clearing the NVRAM should solve the problem.
The Linksys site mentions 'Management Mode' which makes it trivial to recover from bad flashing (answer id 3176). Here's how to do it:
Unplug the power cord from the back of the router.
Hold down the Reset button.
While holding down the Reset button, plug back in the power cord to the router.
Continue to hold the Reset button for five (5) seconds. After five (5) seconds, release the button.
Wait for about one (1) minute. Then, on a computer connected to the router, launch a web browser (for example, Internet Explorer or Mozilla Firefox).
Type in the router's IP address of http://192.168.1.1 into the Address field and press the [Enter] key.
The Management Mode - Firmware Upgrade interface should appear.
После има и други корисни совети, погледај се по ред. Како на пример: If TFTP does not work, try changing your network adapter to 10 Mbps half duplex.
Ако не бидне ни тоа, тогаш крајно решение е да се одлеми епром чипот и потоа да се флешува некој дифолт фирмвер со епром програматор.
