Hello,
   I plan to try installing OpenWRT on my USR 5461, but I would like to make sure that I don't brick the thing as I tinker with it.

  I know a JTAG cable can unbrick almost anything, but I can't build one right now (all my electronics stuff is packed away).  I also don't have / can't build an RS-232 adapter (I need to for other embedded work, but I haven't yet). 

  So, from my understanding, this leaves me with TFTP and web based flashing.  I am pretty sure I can do TFTP to this router like it is (since I think I did it before - my stupidity: reflash over wireless).  Can TFTP rescue all but the worst mishaps?  What things should I avoid doing that would disable or leave me unable to recover over TFTP?

  Also, how usable do you think this is since it only has 8 MB RAM and 2 MB flash?  It does have a USB 1.1 port.  Maybe a swap partition on a flash drive?  How well would this work given that this is USB 1.1?  I know putting some of the file system on the flash drive would help the flash situation (even if it is a bit slow).

  Ideally, I would like to have a web interface, a decent firewall, QOS, a print server (possibly for several printers), chillispot (if possible), multiple SSIDs, maybe an sftp relay, and maybe a (small) fileserver (sftp at minimum, samba if possible).  Is this reasonable given this hardware?  I know at least some of it has been done before: http://forum.openwrt.org/viewtopic.php?id=3344&p=1.

Thanks.

  By the way, great firmware - I just want in on it!

IIRC, you will first need to solder a jumper pins header before you can use a serial-console cable to connect a USR5461 to a computer. I have some USR5461 units as well as some PC2700 DRAM sticks that contain 32MB RAM chips. I am hoping someone knows how to replace the 8MB RAM with this 32MB RAM chip to make this USR5461 works. With only 8MB RAM, it really is pretty hard to run more applications, i.e. asterisk. Doing a swap through a USB v1.1 (even on a v2.0) is definitely not a good idea, AFAIC.

I knew about the header - companies don't populate PCBs with components the end user wont use or didn't pay for.  I would think carefully about the hardware memory upgrade.  It could be quite successful - if you are careful.  These are surface mount ICs - not the world's easiest things to solder.  It can be done by hand - if you haven't done this before, make sure you get a good magnifier (microscope recommended), a fine tip soldering iron, small gauge solder, and a good how to guide.  Also, check out the datasheets for both chips very carefully.  They need to be the same package, compatible memory types, the same bus width, etc: http://wiki.openwrt.org/OpenWrtDocs/Cus … AM_upgrade, http://wiki.openwrt.org/OpenWrtDocs/Har … mens/SE505.

I've read about swapping over USB not being a good idea, but how badly would this work?  Has somebody tried it?  I know switching tasks would likely be slow, but that's OK - I don't intend for it to do lots of things at once.

But what about keeping the thing from being bricked (not accessible over ethernet)?  Any tips?

Well, I tried flashing it with the image located at http://downloads.openwrt.org/kamikaze/7 … m47xx-2.6/.  It wouldn't flash over the web interface (not too surprising), but it seems it did flash over tftp.

The problem is now that I can't get in touch with the thing!  I set my ip to be static in the 192.168.1.x range.  I then tried to telnet to 192.168.1.1.  No good.  Well, then how about another tftp to get me back?  Can't contact it any way.  Not on the orginal ip address (in the 192.168.0.x range), not at the new ip address, not anywhere.  So, I tried the failsafe.  I saw the message "Press reset now, to enter Failsafe!", but I think the reset button is hardwired or something on this router since the reset does indeed reset the router, no matter how long or short I hold it (it causes the message to be broadcast again).

So, how do I go back or forward?  Should tftp still work?  I read that even if boot_wait is diabled, tftp should still be possible (http://forum.openwrt.org/viewtopic.php?id=3474).  What should I try now?  I know the router is at 192.168.1.1 since I used nmap to find it.