TFTP Flashing a Belkin F5D7230
From DD-WRT Wiki
 TFTP Flashing a Belkin F5D7230-4 v1000 or v1444
First, review the basic instructions at TFTP_flash.
Second, note that the F5D7230 v1000 has 4MB of flash memory, and consequently can support DD-WRT mini. v.1223uk also has 4Mb flash. Later models, including v1444, have 2MB of flash and can only support DD-WRT micro. Be sure to get the correct one!
The TFTP server is only available very briefly during the F5D7230's boot process. It can be frustrating to find the appropriate time at which to start the TFTP process. If you start the transfer at the wrong moment, you will receive a timeout error rather than a confirmation message stating the transfer was successful.
To reliably begin a TFTP transfer at the right time:
- Hold down the reset button until the router's LAN status LEDs turn off, then flash all green
- The router LAN status LEDs will then change to all amber
- The router LAN status LEDs will then briefly go off -- this is the point at which you should initiate the TFTP transfer
- If at first you don't succeed, try, try again. It took me dozens of attempts to identify this point in the boot process.
Or you can get a bit of help from this little bash script - it uses a sub-second ping time delay before starting atftp triggertftp
I successfully flashed the v1000 using dd-wrt.v24_generic-8184.bin: http://dd-wrt.com/phpBB2/download.php?id=3149
Another DD-WRT fan successfully flashed the v1444 using dd-wrt.v24_micro_generic.bin: http://www.dd-wrt.com/dd-wrtv2/downloads/stable/dd-wrt.v24%20SP1/Consumer/Belkin/F5D7230_v1444/dd-wrt.v24_micro_generic.bin Yet another v1444 user was also successful at first attempt using dd-wrt.v24_micro_generic.bin, once a hub was installed between PC and router to maintain the PC connection. See below.
Notes: Connecting a switch between the PC and the Belkin may help. This ensures that the PC's network card is active in time to catch the golden TFTP moment. Also, remember that installing DD-WRT will change your router's IP address from 192.168.2.1 to 192.168.1.1. The user will be "root" and password "admin".
The Belkin F5D7321-4 v1000 can be sucessfully flashed with the dd-wrt.v24_micro_generic.bin firmware. It will report the model as the F5D7320-4 v1444 after flashing. The above method works with the windows tftp.exe program. Just make sure your computer is plugged directly into the router and you have manually set your IP address to the same subnet. Once you plug the router back in, wait a split second before clicking upgrade. It might take a few tries but it works.
The v1000 success was after an unsuccessful attempt to use dd-wrt.v24_mini_generic.bin (it did not brick, just reset the stock firmware to factory defaults).
On v1000 (or v1111), only firmwares less than 3.5 MB can be flashed. You must use micro, mini, or build your own via the fw-modification kit. You can't load the v24sp1 nokaid or larger via tftp, web, or command line.
On v1000, mild success with: dd-wrt.v24_mini_generic.bin Although I was left unable to connect an Atheros card under Vista.
Success with: dd-wrt.v24-9517_VINT_mini_usb.bin Atheros card connects and have had no problems
Success using dd-wrt.v24_mini_generic.bin with Belkin F5D7230-4 Version 1223uk
Another note: Don't trust the labels... mine is marked F5D7230-4 VER 1000v, but it is a 1444
system type : Broadcom BCM4712 chip rev 1 cpu model : BCM3302 V0.7
This is important since I tried flashing with the mini which is too large for the memory. The flash installation will act like its successful but when it booted, it was the old firmware. Only the micro image successfully booted, and is working.
bnborg: Success with dd-wrt.v24-13491_Bv2000_micro-plus_ssh.bin by Eko, on F5D7230-4 v2000.
I used the Windows XP x64 tftp.exe. I just prestaged the command, plugged it in, waited for the lights to flash, and hit enter. I waited maybe as much as a second between the light flash and enter. First time was a charm. Getting it to work the way I wanted was another story, but eventually I got there.