[Cricri]

IS there any specific DD-WRT build for WHR-G54s with SD card support for noobs like me?
Also, instead of soldering a SD card slot on cutting out an opening, what if I soldered directly the SD card to the motherboard (i.e. wires from JTAG points to points on the SD card, without card slot). Any reason why that would be a bad idea?
I ask because I have a spare 1GB card around, but no SD slot, and they're not cheap, and I'd like to not mess with the router cosmetics. I wouldn't need the card anyway for anything else.

[Eko]

You can do it.

[Cricri]

Neat, I might give it a go then. I have 23SP3 05/02/07 now, will it support the SD card natively or do I need to compile my own build? Thanks!

[Eko]

It supports it. (but might have problems with 1 gb card. I fixed this. I will pm you latest sp3 now)

[Cricri]

Thanks
*EDIT* Oie, I've been posting in the JTAG thread! Apologies, I shouldn't post after midnight, I've been on a inaccurate posting rampage before going to bed!
Again, apologies for that

[chuckao]

Hi,

My Buffalo WHR G54S is bricked and I don´t know the reason for that. It was working perfectly for 1 year with dd-wrt 23 sp2 and yesterday it was bricked. All ether ports´ leds still on and power led too. So, I have to try to use JTAG cable but I don´t have idea how to make one.

I read good tips in this thread (tks anectine17) however the final idea is not so clear to me.

Anectine17 said:

In Router JTAG connector:

pins 1,3,5,7,9,11 are ground;
pin 2 is 4.4 volts;
pin 4 is TDI;
pin 6 is TDO;
pin 8 is TMS;
pin 10 is TCK;
pin 12 seems to do nothing.

Is it correct?

If yes, so look to my attached picture and you will see which hole correspond to pin 1. (the top-left hole).

Is it correct?

In this same picture I put a modified Eugene´s JTAG schema (tks Eugene [1]) linking my router JTAG connector to PC parallell port.

Could anyone confirm if this schema is correct?

anectine17 said to use 480ohms resitors but Eugene´s schema shows 100ohms.

So, which one is correct?

Finally, supposing that my JTAG is correct so I have to use HairyDairyMaid's tool rev 4.8, isn´t it?

Ok, but I don´t know yet which commands I have to use. My router is bricked and I´m sure that I don´t need to do a backup of its firmware.

Cheers,

[1] - http://lazutkin.com/blog/2006/apr/5/jtag/

[wayland]

Just get stuck in and do it!

First their are already some resistors on the board, at least on the WHR-HP-G54, so I just soldered the wires stright on. Pin one is always identified, as you have spotted.

The J-TAG cable need only be a parralell printer cable with the printer end cut off. It goes into your parralell socket on your PC, if you have an older PC which still has this. You then solder the required wires to the J-TAG pad on the buffalo

Popping the .sys file in the correct windows directory is important, must get this step to work. Hairy Dairy Maid is what you use from the dos prompt to do stuff.

You don't need to erase the whole flash memory, it's usually enough to clear the NV RAM. You may find you need some command line options to actually make it skip a few checks to get it to run.

The principle of J-TAG is that it gives you full access to the data and address bus of the board without the CPU or software running. It means you can poke around in the memory and stuff via your PC. But it only uses a handful of wires so reflashing the whole memory would take a while.

Just get on and do it without worrying about resistors. After all it's bricked so it won't get any worse!

Regards,
Wayland.

[chuckao]

[wayland]

I just used a fine tipped soldering iron and soldered them on. It's not like you will be doing this very often on the same board. My J-Tag cable was a DE25 connector with a strip of ribbon cable from an old IDE cable. I just separated the individual wires at the ends and stripped back a little then soldered then ends on the right pins and pads.

[redhawk0]

anectine17, did you add ~390ohm resistors to your reversed pin pigtail extension? I haven't bricked my G54S yet...but knowing me...it's inevitable.

redhawk

[chuckao]

Hey wayland!!!

I was wrong. There aren´t resistors on the board of WHR-G54S. Please, look the attached picture, you can see resistor spaces but they are not there.

So, I really need to use resistors, isn´t it? But, which one? 100 ohms or 480ohms?

Cheers,

[Iron]

Try it with the 480 ohms first, if it doesn't work try it with 100 ohms... That way you are always safe

[redhawk0]

You need 450-480 ohm resistors.

redhawk

[anectine17]

OK......I've gotten 472 thousand PM's and e-mails asking me to tell you how I built the adapter. I put a LOT of time and money (I ruined 2 WHR's, not to mention the one I bought for HD...resistors, connectors, cable, etc.). I figured since I put the effort and cash into figuring it out, people could do one of 2 things: buy an adapter or cable from me to help offset what I burned up, or figure the simple part of voltages out themselves. Obviously that's not going to happen...everyone wants it for free on a silver platter. Maybe someone will remember this next time I'm stuck on something and am actually offering CASH for a solution, and I won't go totally unnoticed (has happened at least 3 times now)....yeah, I'm a bit annoyed at the whole thing.

Anyway.... HairyDairy and I basically had 3 of the WHR's......he had one and I had 2 so we could work "together" on it. Comparing voltages to those found on the WRT's, we determined that in order to arrive at the same working voltages with the WHR, we needed 480 ohms of resistance. Obviously, (to me anyway) the WHR's don't have any JTAG resistors installed, so all of that resistance must be installed on the cable. So, if you're building a cable just for the WHR, you'll want to use 480 ohm (or thereabouts) resistors, OK? Now, applying the rithmatik I lernded way back when, I deduced that if I was building an adapter to use with my standard JTAG cable, I had to take the 100 ohm resistors already on the cable into consideration....and I came up with 380 ohms for the adapter. 380 + 100 = 480. I've never seen a 380 ohm resistor, so I used 390's and it works fine.

Have fun with it. Next time I'm asking for help with a software or similar issue, remember where this came from and don't blow me off. Thanks.

Alden

[elgolebio]

Ok, JTAG works fine. No 470 or 480 ohm resistors nedeed. Just use 100ohm. Just build a regular JTAG from Openwrt scheme. You don't need to solder pins into your Buffalo, the pins are small enough, that all you have to do is to plug them and they will sit tight. Ofcourse JTAG pinouts in this router are a mirrored version of pinouts from Linksys routers, but that is no problem, just plug the pins upside down the board.

Sorry for my english, I just wanted to tell all that there's no need to make a different cable with 470ohm resistors, and also no need to solder the pins. GOOD LUCK