I ran an early model WRT54G with DD-WRT for a while a number of years ago. That was my last foray into DD-WRT (it's been pfsense and now routeros since). I wanted to give DD-WRT another go and so started looking through my box of bits to see what I might have that would work. After a bit of digging in the parts box and reading online I soon realised most of my gear would run DD-WRT, but a 'micro' build. I'm interested in having a play with some of the extra stuff that DD-WRT has to offer so I needed something with a little more Flash and RAM.
DD-WRT openly recommend a TP-Link TL-WR740N to start with, and for $19AUD from a local store it's a pretty awesome recommendation. Getting into DD-WRT has come down in price since I last looked - which is awesome. Looking at the supported devices list though and what else was available with a little more Flash and RAM (as well as a USB port if possible) I settled on a TP-Link TL-WR842ND v2 for $38AUD:
This router was solely purchased to be hacked, flashed and generally tinkered with, so the first thing I did after taking it out of the box was open it up. I know these routers have a serial header thanks to this page (and many others) and I wanted to see if I could get a serial console first. I found the connections, soldered on a four pin header and connected my 3.3v USB serial adapter:
Once I got the pinout correct, it worked without issue (115200, 8N1). Typing tpl when you see "Autobooting in 1 seconds" will drop you into the uboot prompt:
Next step was to make this serial header externally accessible so I could close it back up but still access the serial console. With a little bit of Dremel work I cut space for a 4 pin female header above the reset button on the back of the case. I hot glued it in place and then soldered in some jumper wires. In hindsight I probably could have removed the first header I soldered in and had the jumper wires run straight to the board, but the case has room so I left it in:
I closed the case back up and got ready to flash DD-WRT with my new serial console open to watch the process, which worked without issue (serial console not required, but super extra nerd cred for having it). I flashed the latest version at the time which was 05-27-2015-r27086. I first flashed the factory-to-ddwrt.bin through the TP-Link web interface, and then flashed the tl-wr842ndv2-webflash.bin through the DD-WRT web interface.
The final step was to add a sticker to complete things:
I'll need some time to get to know DD-WRT again, but I have the comfort of a serial console if things go sideways.
