pins on rt-ac56u

[stevocz]

hi.

what free places for pins are this?

 

[Pierino]

The left most one in the picture is probably the serial port, which surprises me.
The rt-n66, rt-ac66, rt-16 I have fixed all had the header already soldered in.

The right, lowest one, I would guess is jtag.
The other two, idk.

 

[hggomes]

Those are Serial port, 2x JTAG ports and SPI port.

 

[dzfacts]

How can I flash my bricked Rt-ac56u with a JTAG cable, where is this JTAG cable available for buying ?

 

[leoo2001]

I also have bricked AC56U which is not recoverable by serial cable (the nvram refuses to initialize ethernet). If somebody may enlighten us how to do it with JTAG I will deeply grateful.

 

[RMerlin]

I also have bricked AC56U which is not recoverable by serial cable (the nvram refuses to initialize ethernet). If somebody may enlighten us how to do it with JTAG I will deeply grateful.

This is usually recoverable by clearing the nvram from the CFE, and then rebooting.

 

[leoo2001]

Have done this many times but with no luck. Cant see even bootloader trying.

CFE> nvram erase
*** command status = 0
CFE> reboot▒Digital core power voltage set to 0.9375V
Decompressing...done
Detect CPU turbo button...

CFE version 6.37.14.73 (r448163) based on BBP 1.0.37 for BCM947XX (32bit,SP,)
Build Date: 二  2月 18 09:46:43 CST 2014 (ham@xpdev)
Copyright (C) 2000-2008 Broadcom Corporation.

Init Arena
Init Devs.
Boot partition size = 262144(0x40000)
DDR Clock: 400 MHz
Info: DDR frequency set from clkfreq=800,*533*
Warning: invalid DDR setting of 533 MHz ignored. DDR frequency will be set to 400 MHz.
CPU type 0x0: 800MHz
Tot mem: 262144 KBytes

CFE mem:    0x00F00000 - 0x01795510 (9000208)
Data:       0x00F4DB6C - 0x00F4E038 (1228)
BSS:        0x00F4E048 - 0x00F93510 (283848)
Heap:       0x00F93510 - 0x01793510 (8388608)
Stack:      0x01793510 - 0x01795510 (8192)
Text:       0x00F00000 - 0x00F442D8 (279256)

Committing NVRAM...done
Waiting for wps button release...donDigital core power voltage set to 0.9375V
Decompressing...done
Digital core power voltage set to 0.9375V

SHMOO VER 1.13

PKID07DC06011801080000000000001A103F01000000

S300402F3
000025D0


RDLYW0 00000004

RDENW0 00000060

RDQSW0

    0000000000111111111122222222223333333333444444444455555555556666
    0123456789012345678901234567890123456789012345678901234567890123
 00 -----------++++++++++++++++++++++++++X++++++++++++++++++++++++++
 01 ----------------++++++++++++++++++++++++X+++++++++++++++++++++++
 02 -------------+++++++++++++++++++++++++X+++++++++++++++++++++++++
 03 ----------+++++++++++++++++++++++++++X++++++++++++++++++++++++++
 04 -------++++++++++++++++++++++++++++X++++++++++++++++++++++++++++
 05 --------------+++++++++++++++++++++++++X++++++++++++++++++++++++
 06 ------------++++++++++++++++++++++++++X+++++++++++++++++++++++++
 07 ------------++++++++++++++++++++++++++X+++++++++++++++++++++++++
 08 --+++++++++++++++++++++++++++++++X++++++++++++++++++++++++++++++
 09 ---------+++++++++++++++++++++++++++X+++++++++++++++++++++++++++
 10 --+++++++++++++++++++++++++++++++X++++++++++++++++++++++++++++++
 11 ---++++++++++++++++++++++++++++++X++++++++++++++++++++++++++++++
 12 ----++++++++++++++++++++++++++++++X+++++++++++++++++++++++++++++
 13 ----++++++++++++++++++++++++++++++X+++++++++++++++++++++++++++++
 14 -----+++++++++++++++++++++++++++++X+++++++++++++++++++++++++++++
 15 -----+++++++++++++++++++++++++++++X+++++++++++++++++++++++++++++


PW0

    0000000000111111111122222222223333333333444444444455555555556666
    0123456789012345678901234567890123456789012345678901234567890123
 00 ------------++++++++++++++++++++++++++X+++++++++++++++++++++++++
 01 ----------------++++++++++++++++++++++++X+++++++++++++++++++++++
 02 --------------+++++++++++++++++++++++++X++++++++++++++++++++++++
 03 ---------+++++++++++++++++++++++++++X+++++++++++++++++++++++++++
 04 -----+++++++++++++++++++++++++++++X+++++++++++++++++++++++++++++
 05 --------------+++++++++++++++++++++++++X++++++++++++++++++++++++
 06 ----------+++++++++++++++++++++++++++X++++++++++++++++++++++++++
 07 ------------++++++++++++++++++++++++++X+++++++++++++++++++++++++
 08 ++++++++++++++++++++++++++++++++X+++++++++++++++++++++++++++++++
 09 ---------+++++++++++++++++++++++++++X+++++++++++++++++++++++++++
 10 ---++++++++++++++++++++++++++++++X++++++++++++++++++++++++++++++
 11 ----++++++++++++++++++++++++++++++X+++++++++++++++++++++++++++++
 12 ---++++++++++++++++++++++++++++++X++++++++++++++++++++++++++++++
 13 ---++++++++++++++++++++++++++++++X++++++++++++++++++++++++++++++
 14 -----+++++++++++++++++++++++++++++X+++++++++++++++++++++++++++++
 15 ---++++++++++++++++++++++++++++++X++++++++++++++++++++++++++++++


NW0

    0000000000111111111122222222223333333333444444444455555555556666
    0123456789012345678901234567890123456789012345678901234567890123
 00 ------------++++++++++++++++++++++++++X+++++++++++++++++++++++++
 01 ----------------++++++++++++++++++++++++X+++++++++++++++++++++++
 02 -------------+++++++++++++++++++++++++X+++++++++++++++++++++++++
 03 ---------+++++++++++++++++++++++++++X+++++++++++++++++++++++++++
 04 -------++++++++++++++++++++++++++++X++++++++++++++++++++++++++++
 05 ---------------++++++++++++++++++++++++X++++++++++++++++++++++++
 06 ------------++++++++++++++++++++++++++X+++++++++++++++++++++++++
 07 ------------++++++++++++++++++++++++++X+++++++++++++++++++++++++
 08 --+++++++++++++++++++++++++++++++X++++++++++++++++++++++++++++++
 09 ----------+++++++++++++++++++++++++++X++++++++++++++++++++++++++
 10 ----++++++++++++++++++++++++++++++X+++++++++++++++++++++++++++++
 11 ----++++++++++++++++++++++++++++++X+++++++++++++++++++++++++++++
 12 ----++++++++++++++++++++++++++++++X+++++++++++++++++++++++++++++
 13 -----+++++++++++++++++++++++++++++X+++++++++++++++++++++++++++++
 14 ------+++++++++++++++++++++++++++++X++++++++++++++++++++++++++++
 15 ----++++++++++++++++++++++++++++++X+++++++++++++++++++++++++++++


WRDQW0

    0000000000111111111122222222223333333333444444444455555555556666
    0123456789012345678901234567890123456789012345678901234567890123
 00 -+++++++++++++++++++++++++++++++X++++++++++++++++++++++++++++++-
 01 ----+++++++++++++++++++++++++++++X+++++++++++++++++++++++++++++-
 02 +++++++++++++++++++++++++++++++X+++++++++++++++++++++++++++++++-
 03 +++++++++++++++++++++++++++++++X+++++++++++++++++++++++++++++++-
 04 +++++++++++++++++++++++++++++++X+++++++++++++++++++++++++++++++-
 05 +++++++++++++++++++++++++++++++X+++++++++++++++++++++++++++++++-
 06 +++++++++++++++++++++++++++++++X+++++++++++++++++++++++++++++++-
 07 --++++++++++++++++++++++++++++++X++++++++++++++++++++++++++++++-
 08 +++++++++++++++++++++++++++++++X+++++++++++++++++++++++++++++++-
 09 +++++++++++++++++++++++++++++++X+++++++++++++++++++++++++++++++-
 10 +++++++++++++++++++++++++++++++X+++++++++++++++++++++++++++++++-
 11 +++++++++++++++++++++++++++++++X+++++++++++++++++++++++++++++++-
 12 +++++++++++++++++++++++++++++++X+++++++++++++++++++++++++++++++-
 13 +++++++++++++++++++++++++++++++X+++++++++++++++++++++++++++++++-
 14 +++++++++++++++++++++++++++++++X+++++++++++++++++++++++++++++++-
 15 +++++++++++++++++++++++++++++++X+++++++++++++++++++++++++++++++-


WRDMW0 00000031
WRDMW0 00000031


ADDR

    0000000000111111111122222222223333333333444444444455555555556666
    0123456789012345678901234567890123456789012345678901234567890123
 00 +++++++++++++++++++++++++++++++X+++++S++++++++++++++++++++++++++

Decompressing...done
Detect CPU turbo button...

CFE version 6.37.14.73 (r448163) based on BBP 1.0.37 for BCM947XX (32bit,SP,)
Build Date: 二  2月 18 09:46:43 CST 2014 (ham@xpdev)
Copyright (C) 2000-2008 Broadcom Corporation.

Init Arena
Init Devs.
Boot partition size = 262144(0x40000)
DDR Clock: 533 MHz
Info: DDR frequency set from clkfreq=800,*533*
CPU type 0x0: 800MHz
Tot mem: 262144 KBytes

CFE mem:    0x00F00000 - 0x01795510 (9000208)
Data:       0x00F4DB6C - 0x00F4E038 (1228)
BSS:        0x00F4E048 - 0x00F93510 (283848)
Heap:       0x00F93510 - 0x01793510 (8388608)
Stack:      0x01793510 - 0x01795510 (8192)
Text:       0x00F00000 - 0x00F442D8 (279256)

Null Rescue Flag.
Hello!! Enter Rescue Mode: (by Force)

Reading :: TFTP Server.
Failed.: Error
Loader:raw Filesys:raw Dev:nflash0.os File: Options:(null)
Loading: .... 4034784 bytes read
Entry at 0x00008000
Starting program at 0x00008000
console [ttyS0] enabled, bootconsole disabled
serial8250.0: ttyS1 at MMIO 0x18000400 (irq = 117) is a 16550
brd: module loaded
loop: module loaded
pflash: found no supported devices
bcmsflash: found no supported devices
Boot partition size = 524288(0x80000)
lookup_nflash_rootfs_offset: offset = 0x200000
nflash: squash filesystem with lzma found at block 28
Creating 4 MTD partitions on "nflash":
0x000000000000-0x000000080000 : "boot"
0x000000080000-0x000000200000 : "nvram"
0x000000200000-0x000004000000 : "linux"
0x00000039b49c-0x000004000000 : "rootfs"
PPP generic driver version 2.4.2
PPP MPPE Compression module registered
NET: Registered protocol family 24
PPTP driver version 0.8.5
u32 classifier
    Actions configured
Netfilter messages via NETLINK v0.30.
nf_conntrack version 0.5.0 (3992 buckets, 15968 max)
xt_time: kernel timezone is -0000
ip_tables: (C) 2000-2006 Netfilter Core Team
TCP cubic registered
NET: Registered protocol family 10
ip6_tables: (C) 2000-2006 Netfilter Core Team
NET: Registered protocol family 17
L2TP core driver, V2.0
PPPoL2TP kernel driver, V2.0
802.1Q VLAN Support v1.8 Ben Greear <greearb@candelatech.com>
All bugs added by David S. Miller <davem@redhat.com>
Registering the dns_resolver key type
Northstar brcmnand NAND Flash Controller driver, Version 0.1 (c) Broadcom Inc. 2012
NAND device: Manufacturer ID: 0x01, Chip ID: 0xf1 (AMD NAND 128MiB 3,3V 8-bit)
Spare area=64 eccbytes 56, ecc bytes located at:
 2 3 4 5 6 7 8 9 10 11 12 13 14 15 18 19 20 21 22 23 24 25 26 27 28 29 30 31 34 35 36 37 38 39 40 41 42 43 44 45 46 47 50 51 52 53 54 55 56 57 58 59 60 61 62 63
Available 7 bytes at (off,len):
(1,1) (16,2) (32,2) (48,2) (0,0) (0,0) (0,0) (0,0)
Scanning device for bad blocks
Options: NO_AUTOINCR,NO_READRDY,BBT_SCAN2NDPAGE,
Creating 2 MTD partitions on "brcmnand":
0x000004000000-0x000007ec0000 : "brcmnand"
0x000007ec0000-0x000008000000 : "asus"
VFS: Mounted root (squashfs filesystem) readonly on device 31:3.
devtmpfs: mounted
Freeing init memory: 212K
## mknod /dev/null: File exists
## mknod /dev/console: File exists
1: set_action 0

Strangely Wps button is functioning because if pressed power led starts flashing very fast and boot is stopped until button is released.

 

[RMerlin]

That's the same problem I frequently encounter while working with the AC56. The trick is to keep Ctrl-C pressed down from the moment you apply power to the router. There is a VERY short window during which Ctrl-C will work in breaking the boot process, and leaving you at the CFE prompt.

 

[leoo2001]

I was aware of this trick and there is no problem to enter in the CFE prompt. The code that I have copied starts just after i already executed manually "nvram erase" and was holding reset button hoping to get the router in recovery mode. No matter how many times I enter in CFE and execute the erase command it never gets Ethernet initialized. Thats why im looking for way to reflash CFE

 

[RMerlin]

Instead of rebooting after clearing nvram, try a normal boot ("go" if I remember correctly).

 

[leoo2001]

Done that. Definitely "no go" for me. Still reboot loop only. The strange thing is that all CFE commands are available, but none of them can bring the Ethernet back.

 

[RMerlin]

Done that. Definitely "no go" for me. Still reboot loop only. The strange thing is that all CFE commands are available, but none of them can bring the Ethernet back.

All I can think of then would be that the switch itself is defective, assuming you didn't tinker with the CFE partition itself.

 

[tosiek]

Have anyone explains the pinout?

What pin is TDI,TDO,TMS,TCLK ?

 

[greekleo89]

Hi all,

I seem to have bricked my ac56u too. It was on ddwrt, I reverted to stock and then I put the merlin firmware on. When it finished installing it said to manually reboot the router, which I did but after this it comes on for 10 secs and reboots, I've tried the different reset methods but no luck.

I ordered a ttl to USB so that I can try and get into the console, my question is how do I make sure that it doesn't reboot within ten seconds so that I can clear the nvram. There are four pins. How do I know which one to connect it to as they are not labelled ?

Thanks

 

[Pierino]

You have to stop the boot process by hitting control +c

 

[greekleo89]

You have to stop the boot process by hitting control +c

Thank you very much for your reply, there are 4 pins on the board, which ones do I use?
Also what settings should I set in putty for the speed?

Thanks

 

[Pierino]

I don't know which they are. You only need to use ground, tx and rx.
You can figure out which s ground.
Read this https://www.dd-wrt.com/wiki/index.php/Serial_Recovery.
I also linked in there the type of USB to uart adapter to get.

I found a good picture http://s020.radikal.ru/i721/1407/73/9e69f1495a82.jpg