I'd like to thank those in this thread for the valuable information that allowed me to recover my bricked
wrt54gr.
I had installed OpenWRT on it and it worked for a few weeks but then stopped talking to the outside world after updating some network settings from the web interface. No HTTP access. No ping access. No TFTP access. The reset button did nothing.
I could telnet to it only by connecting it to another router and using that DHCP supplied address (in this case 192.168.1.3). It was frustrating knowing it was alive, but unusable. I found a recovery program in /etc, but it reported that it wasn't supported on this platform. There was no nvram support since this version of OpenWRT was running linux 2.6.24.7. Further investigation determined that mtdBlock1 was broken and mtdblock0 was also inaccessible. MTD erase nvram didn't work. firstboot didn't work. I could find no easy way to recover this box.
In the end, I ordered the SCHMartBoard RS232-TTL converter ($15). I removed the header pins from an old SB16 sound card (circa 1996) and used them to solder a serial header and Jtag header to the router PCB. I then crafted from some old cd-rom sound cables a wire harness to go between the serial port and converter. It all worked on the first try!
Once I had access to the serial console, it was just a matter of hitting CTRL-C at power up to get to CFE (REDBOOT>) command mode, start up the TFTP daemon (REDBOOT> tftpd), and then use tftp from windows to upload the original factory firmware.
I couldn't have done any of this without the information in this and other threads.
Thanks again for sharing your knowledge so that others can benefit!
Doug.
(Last edited by doug80638 on 10 Dec 2009, 01:47)