[dale_gribble39]

Newer model, JP2 (10-pin). Point of reference would be using a multimeter to test from a known ground point on the SoC board to find Vcc and GND pins and then use the layout referenced above that photo. That layout actually references pin numbers which are marked on your board, though - at least you can verify if correct, if absolutely necessary.

[Cosmic11do2]

Dale, since you linked to the uarts at AZ (thanks) I should mention that my previous attempt to use the the Serial Recovery wiki
https://wiki.dd-wrt.com/wiki/index.php/Serial_Recovery
and the link referencing uarts
http://www.dx.com/p/usb-to-uart-5-pin-cp2102-module-serial-converter-81872#.VqrGiEo8KK0
generates a 404 error. It should be updated or removed or generic search term suggested there.

[kernel-panic69]

Wiki was already updated yesterday with another link from eBay that Malachi put in the forum. Thanks for looking out, though.

[Cosmic11do2]

I finally got my UART and some pin headers and rigged up the connections to my WRT54GSv4. I was able to follow the Barryware Instructions for Linksys in the Serial Recovery page.
https://wiki.dd-wrt.com/wiki/index.php/Serial_Recovery

I was able to pound the Ctrl-C like the "Slotted Pig" in Toy Story 2 and got the prompt. I did the nvram erase but when I tried the
flash -ctheader : flash1.trx [enter]
step I got a failure. I tried several times with new instances of both tftp and putty. The message is
Failed. I/O Error
*** command Status = -4

The settings I'm using in Putty are 192.168.1.1 for the server and WRT54GS-v4_1.06.3.002_fw.bin for the file as recommended as the Std. Linksys firmware to use as recommended in the version specific instructions at
https://wiki.dd-wrt.com/wiki/index.php/Linksys_WRT54GS_v4.0

The entire putty session screen text looks like this:
(Ignore my typo on the first try where I forgot the hyphen. Not important as this is the same problem and error message when I tried w/o the typo)

-----------------


CFE version 1.0.37 for BCM947XX (32bit,SP,LE)
Build Date: Tue Jun 28 16:38:04 CST 2005 (root@localhost.localdomain)
Copyright (C) 2000,2001,2002,2003 Broadcom Corporation.

Initializing Arena
Initializing Devices.

No DPN
et0: Broadcom BCM47xx 10/100 Mbps Ethernet Controller 3.90.37.0
CPU type 0x29008: 200MHz
Total memory: 16384 KBytes

Total memory used by CFE: 0x80300000 - 0x803A3620 (669216)
Initialized Data: 0x80339530 - 0x8033BC40 (10000)
BSS Area: 0x8033BC40 - 0x8033D620 (6624)
Local Heap: 0x8033D620 - 0x803A1620 (409600)
Stack Area: 0x803A1620 - 0x803A3620 (8192)
Text (code) segment: 0x80300000 - 0x80339530 (234800)
Boot area (physical): 0x003A4000 - 0x003E4000
Relocation Factor: I:00000000 - D:00000000

Boot version: v3.6
The boot is CFE

mac_init(): Find mac [00:1A:70:3F:70:47] in location 1
Nothing...

eou_key_init(): Find key pair in location 0
The eou device id is same
The eou public key is same
The eou private key is same
Device eth0: hwaddr 00-1A-70-3F-70-47, ipaddr 192.168.1.1, mask 255.255.255.0
gateway not set, nameserver not set
Automatic startup canceled via Ctrl-C
CFE> ^C
CFE> ^C
CFE> nvram erase
*** command status = 0
CFE> flash ctheader : flash1.trx
:: Device not found
*** command status = -6
CFE> flash -ctheader : flash1.trx
Reading :: CODE Pattern is CORRECT!
upgrade_ver[v1.6.3] upgrade_ver[10603] 4712_ver[10000]
Failed.: I/O error
*** command status = -4
CFE>

[kernel-panic69]

1) Is the router responding to pings from the client device? What was the output of 'devinfo show' and 'show devices'?

2) Keep in mind that 192.168.1.1 is the router's CFE default IP address unless you changed it.

3) Your client PC should be 192.168.1.2 or any *other* IP but .1.

4) You should also be using the TFTP client (either TFTPD32 4.52, the Linksys GUI client available on their website, etc, or the Draytek utility. Some further reading that may or may not be helpful:

TFTP Flash - DD-WRT Wiki

Everything you Ever Wanted to know about Serial - TTL

[Cosmic11do2]

Howdy kernel-panic69, thanks for the response.

Please see earlier in this thread about pings, as in no response leading to others suggestions of trying the serial repair.
The 192.168.1.1 is the original setting AFAIK for the router and my laptop IPv4 is set to 192.169.1.9 IIRR. Anyway on the same net. Also note that I was able to connect with putty and the CTRL-C and later commands OK so I think that the connection via the UART to the board serial port is working correctly.

The tftp I am using is the tftp2 that I got via a link from the serial recovery page, or maybe the Peacock page, I can't remember just now but it is the one recommended.

Do you think that there is a problem with trying to flash the original Linksys firmware recommended in the model specific page? I was trying to upgrade to that when I originally bricked the router, again see the earlier notes at the start of this thread.

Any thoughts on the specific error message and any suggested next steps appreciated.

[kernel-panic69]

Well, if you entered the commands correctly and clicked or entered "put", etc. properly and you get the I/O error like you did, the only thing I can think of is the ethernet switch has died (hardware failure). The devinfo show and show devices would show you the IP address, etc. and other things of importance, which is why I asked what the output was. Also the output of nvram show could shed some light, perhaps. If all that looked good INCLUDING your MAC address(es) (see router label), then I relent back to possible hardware failure. I've even read that a 30-30-30 on WRT54 can go awry, but if neither a hard reset nor a serial flash is working, might be time to chuck it in the electronics recycle bin.

[Cosmic11do2]

Howdy K-P69,

Well, I missed your request for the output of devinfo show and show devices so this morning I went back with Putty to do the Ctrl-C thang again and get that for you. Hmmmm, now, no matter how fast I hammer the Ctrl-C I can no longer interrupt the boot. But then I noticed that the power light was no longer blinking and the LAN 1 was. So I pinged it from the putty window and a DOS window and got responses

C:\Users\dunwell>ping 192.168.1.1

Pinging 192.168.1.1 with 32 bytes of data:
Reply from 192.168.1.1: bytes=32 time=1ms TTL=64
Reply from 192.168.1.1: bytes=32 time<1ms TTL=64
Reply from 192.168.1.1: bytes=32 time<1ms TTL=64
Reply from 192.168.1.1: bytes=32 time<1ms TTL=64

So then I tried a browser window and got the router login. Once logged in I see that it is Linksys V1.06.3!!! Ta Da!

So even though the tftp and putty reported errors when I tried to flash it must have succcded somehow.

Is it normal once a router is actually working correctly to not be able to do the boot interrupt or was I just not as fast as the "Slotted Pig" even though I tried multiple times?

So the end story is that I am now back to a normal bog standard Linsys system and I can try again to install dd-wrt by the instructions at
https://wiki.dd-wrt.com/wiki/index.php/Linksys_WRT54GS_v4.0

Is this still the latest/greatest set of instructions to follow for a WRT54GSv4? If not, please advise.

Further, this thread kind of wandered far from the original title. If it would be helpful I could start another thread with details of step-by-step and URLs of the sites I followed and places I got the UART and pin header strips and photos of the v4 serial port w/header.

And last of all, I bought a 3-pack of UARTs and a 10-pack of pin headers so if anyone wants the extras I'd be glad to drop them in the mail. Please PM me with an address or we can take it off-board and email.

[kernel-panic69]

Stranger things have happened, but you should still be able to break boot on stock firmware unless there is no boot_wait flag set in nvram / CFE. I think this is one of those devices that you have to make sure that is set to 1 so you can break boot with CTRL+C. That wiki is still relevant and usable to install DD-WRT, and you should start with the linked file (dd-wrt.v24_mini_wrt54gsv4.bin), but for upgrades, you should be able to use the dd-wrt.v24_mini_generic.bin from a current release (currently 49492). For what it's worth, you *should* be able to use the dd-wrt.v24_mini_wrt54gsv4.bin from the current release for initial flash without issue. I would advise to have your serial console / PuTTY up and running just in case something goes awry, whichever path you take. I don't see a problem with leaving all of the discussion in a single thread to keep for future reference, but that is just my own opinion and perspective on things.

[Cosmic11do2]

Thanks for the follow up and verification, K-P89. I do have both those .bin files already downloaded so I'll try a go with them sequentially and report back.

When you say " I would advise to have your serial console / PuTTY up and running just in case something goes awry, " do you mean with the boot interrupted with Ctrl-C or just putty running looking at 192.168.1.1 while I run the Upgrade from the LInksys interface under Administration/Firmware Upgrade?

I'll follow your advise and do a Post Mortum Summary in this thread with any relevant info. It is probably better to keep it all together.

[kernel-panic69]

[Cosmic11do2]

Following Kernal-Panic69's advice I tried to follow the instructions for the model specific v4 of dd-wrt

I'm attaching a file is the output of putty connected to the WRT54GSv4. It is pretty long but may contain info that is relevant to what went wrong.
- I have a USB serial UART connected to the serial port and putty
reading through that. The router has Std. Linksys 1.06.3.002
firmware installed. I also have LAN port 1 connected to my laptop
with win10 and a window up to 192.168.1.1

The steps I took are
- do a 30/30/30 boot
- Re-open the browser to the Linksys interface and go to Admin/Upgrade
and point at the dd-wrt version dd-wrt.v24_mini_wrt54gsv4.bin
and install. Afer a long time the browser said it was Complete but clicking
the Continue button did nothing. I had to re-start the browser window again
and then I got the dd-wrt login in screen and used admin/admin to log in.

As per the WRT54GSv4 specific page instructions I then did another 30/30/30
reboot. This time I got the continuous flashing power light and LAN 1 light
lit solid. A ping from a DOS window give TTL=100

Pinging 192.168.1.1 with 32 bytes of data:
Reply from 192.168.1.1: bytes=32 time=1ms TTL=100
Reply from 192.168.1.1: bytes=32 time=1ms TTL=100
Reply from 192.168.1.1: bytes=32 time=1ms TTL=100
Reply from 192.168.1.1: bytes=32 time=1ms TTL=100

So it looks to be semi-bricked again. The putty window is at the CFE prompt. Perhaps I didn't wait long enough even though I did wait 5 minutes before trying the hard reboot.

so according to the Peacock thread section 6) perhaps I should try to flash
via tftp2 pointing to the dd-wrt firmware dd-wrt.v24_mini_generic.bin???

Please advise

[kernel-panic69]

Start over and when you flash to DD-WRT, don't 30/30/30. You can use the Administration -> Factory defaults page to reset after initial flash if you absolutely have to. It seems that a possible ill-timed or quirky execution of the 30-30-30 is resulting in a brick, so probably best to leave it alone. Get it to the current release and then reset via ~10 sec. push of button or via webUI. You can go as far as an 'nvram erase && reboot' via telnet, but you shouldn't have to unless the other methods don't give satisfactory results.

[Cosmic11do2]

Thanks for all the help and suggestions K-P 69!! We have lift off. I will later coagulate all my notes and links and such into one clot and post up a final Post Mortum Summary. But the short answers seems to be to leave off the 30mode-hard boots for the v4 router and just let it sit for 5 minutes between flashes. Again, more later and thanks for the help.

[Cosmic11do2]

This is a final Summary Post for this thread gathering together all the relevant information into one place. The information and topics under the original heading have wandered rather far afield but there is some good info there if you choose to read through. If you are more interested in just getting your bricked WRT545GSv4 going again stick to the info in this post.

The gist of the issue is that while trying to install dd-wrt on my router it bricked. I then went looking for how to repair it. Many things were tried and much was learned but the bottom line seems to be that either MY router or the v4 of WRT54GS is sensitive to what is called the Hard Boot (30/30/30). See the Peacock thread for more on that.

Note that I am doing all this from a Windoz 10 box.

Important Reading:
- A MUST is what is called the Peacock Thread https://forum.dd-wrt.com/phpBB2/viewtopic.php?t=51486 This contains all the info you will need or links to more info pertaining to all things dd-wrt and at least Linksys routers in general.
- The thread on Serial Recovery https://wiki.dd-wrt.com/wiki/index.php/Serial_Recovery in general
- The WRT54GSv4 SPECIFIC flash/recovery thread https://wiki.dd-wrt.com/wiki/index.php/Linksys_WRT54GS_v4.0
- Also useful is the page on How to Flash https://wiki.dd-wrt.com/wiki/index.php/Tftp_flash

Hardware:
I was not able to find a matching image of the v4 board showing the Serial and JTAG ports with pin identification. The best was this: https://oriolrius.cat/article_fitxers/1602/serial.html It isn't the same model but the pinouts are correct EXCEPT that on the v4 board it is JP2 not JP1 that is the serial port. Use this just for getting the pins and it shows how to take apart the box. NOTE: Use the ttyS0 ports, not the ttyS1 as is noted by Redhawk0 at the head of the Serial Recovery thread.
- Addendum: I later was shown this as well, with excellent photos https://openwrt.org/toh/linksys/wrt54g#serial_port

The items I purchased were a USB UART adapter https://smile.amazon.com/dp/B08BND69FG?psc=1&ref=ppx_yo2ov_dt_b_product_details This is a pack of three but you can get a single one at https://www.ebay.com/itm/NEW-CP2102-USB-2-0-to-UART-TTL-6PIN-Module-Serial-Converter-Free-Cables-/201497833130 I got the three pack because they come shrink-tubing protected. I also bought some pin headers so that I could just slip on the included cable ends. https://smile.amazon.com/dp/B07PKKY8BX?psc=1&ref=ppx_yo2ov_dt_b_product_details I unfortunately live in what is now an electronics supply free zone so I had to order from AhMaZon and a 10-pack. If you have a local supply use the data from the above link for size/type.

[I don't know how to insert photos inline so they ended up at the bottom, look there. Further, there seems to be a limit of three photos regardless of size, so my first shot of the bare serial port did not get included.]
The photos show the WRT54GSv4 with two JP ports with JP2 being the serial. I soldered in the pin header strip, note it is on the 2 - 10 pin row for ttyS0. To make sure I didn't Gorff anything I put a piece of tape over the pins and labeled them. Last of all I connected the UART with the supplied cable. NOTE: Remember that Tx from UART goes to Rx of the board and Tx of the board goes to Rx on the UART. Again, thanks to Redhawk0 in the Serial Recover thread for making that clear.

So once the UART and board are connected, now plug the UART into a USB port. Connect an ethernet cable RJ45 or whatever from the computer into the LAN port 1 of the router. Also connect the WAN port to your network assuming you still have one working to the outside world, some of the reboot process later on seemed to indicate it wanted a WAN connect. No NOT apply power yet.

Software:
For flashing the firmware I downloaded tftp2 from here https://www.3iii.dk/linux/dd-wrt/tftp2.exe as recommended in one of the threads. There is no install, just an .exe file so I made a shortcut on my Windows desktop.
For my serial interface I got Putty from https://www.chiark.greenend.org.uk/~sgtatham/putty/latest.html and took the 64 bit version. This does take an install. The instructions in the Serial Recovery thread are good give the proper Serial settings for putty but are a bit brief if you are not familiar with this sort of software. Look at https://www.ssh.com/academy/ssh/putty/windows#configuration-options-and-saved-profiles for additional info on using Putty and getting the interface set up. I put in the suggested configurations and then saved it for easy access. My Device Manager showed that the UART was Com3. Note that you have to have the UART plugged in for Device Manager or Putty to actually be able to connect and see it. Plug it into a USB port right on your machine, not an USB extension module so that later when you are trying to interrupt the boot it has the fastest connection.

Firmware:
[Modified: Ignore the parts in this section in italics. This turned out to be not needed but is left for continuity]
As per the device specific page I followed the links provided there to get the Original Linksys WRT54GS-v4_1.06.3.002_fw.bin firmware http://www.dd-wrt.com/phpBB2/viewtopic.php?p=680620#680620. Then I got the two dd-wrt firmware versions, first the version specific one dd-wrt.v24_mini_wrt54gsv4.bin at https://download1.dd-wrt.com/dd-wrtv2/downloads/betas/2022/07-14-2022-r49492/broadcom/dd-wrt.v24_mini_wrt54gsv4.bin and also the r49492 generic one dd-wrt.v24_mini_generic.bin at https://download1.dd-wrt.com/dd-wrtv2/downloads/betas/2022/07-14-2022-r49492/broadcom/dd-wrt.v24_mini_generic.bin Save these off in a folder somewhere that is easy to reference with Windows Explorer.

At this point we are ready to go.
First, fire up tftp and put in the IP address of your router. If it is bricked and you have likely done various resets on it then it is likely 192.168.1.1, at least try that. Browse to the Linksys 1.06.3.002 version .bin file you saved but don't do anything further, just have it ready to go.
Next start Putty and run your saved configuration. It should pop up a black window ("The Dark Place"). At this point we are now partly following the instructions in the Serial Recovery thread under the heading of "Barryware Instructions for Linksys". First you need to interrupt the boot sequence as the board powers up. You may want help with this so you can bang on the Ctrl-C key like Hamm the "Slotted Pig" in Toy Story 2 and someone else plugs in the power. If all goes well you will get the cfe> prompt. If it continues booting, just unplug and try again till you get the prompt. Then enter
nvram erase [and hit the Enter key]
Now enter the command
flash -ctheader : flash1.trx
but WAIT to press Enter. Hover your cursor over the Upgrade button in the tftp2 window, then almost simultaneiously press the Enter key for Putty and click the Upgrade button in tftp. Some stuff will go by in putty but eventually it will stop and you will see the cfe prompt again and one hopes that you get confirmation of success in the tftp window.
Now enter the command
go [Enter]
Putty will have a bunch of stuff roaring by but eventually it will stop.

NOW - DO NOTHING for at least five (5) minutes. Go get coffee, pet the cat, play with the dog, etc. Once everything has settled, do NOT do any resets or hard boots or the like. If there is no cfe prompt in the putty window try typing in a benigne command like "show devices" and see if it comes back with the prompt. If not, then unplug the power and go through the Ctrl-C boot interrupt procedure again till you get the prompt.

Go to your tftp2 window but now browse to the firmware you saved for dd-wrt version 4 specific .bin file. This time you do not need to do an nvram erase step but proceed to the flash step and do it all again. Repeat the Go step and again wait at least 5 minutes w/o doing any resets or hard boots.

Modified: [Ignore this paragraph in italics. Left in for continuity. See the two post following this to see why.}
This may be sufficient for you, but I did one more step and flashed the wrt.v24_mini_generic.bin. To do this I used the regular update procedure since at this point I could open a browser to 192.168.1.1 and I got the dd-wrt login prompt. That uses admin for the name and admin for the password. I went to the Administration tab and then the Firmware Upgrade tab and browsed to the wrt.v24_mini_generic.bin file I saved and pressed Upgrade. All went well and it upgraded and finished. It showed afterward that it was Firmware: DD-WRT v3.0-r44715 mini (11/03/20) which is a bit odd since I thought it was rev49492 that was being installed. I may double check my downloaded file and try it again later.

Note that for the second flash of the dd-wrt firmware it might have been possible to do that via a standard Upgrade process from the browser interface. I still had the cfe prompt so I just did it directly there through the serial interface. If you lose the cfe prompt you might check to see if you can access the browser interface and do the second flash there.

That competed my Brick->Post Mortum -> Recovery process and I then proceeded to configure the router and save off the configuration as a backup.