1 (edited by cyker 2012-09-06 01:45:38)

Topic: Serial port on TP-LINK MR11U

Has anyone tested the serial port on TP-LINK MR11U? What are the pinouts (VCC/GND/TX/RX)?

Are there any pins on the board that need to be short-circuited to use the serial port?

I don't have a multimeter or USB-TTL wire at hand now, but I'm planning to follow the guide at http://wiki.openwrt.org/doc/hardware/port.serial. So I'd appreciate it if anyone could point out a 'known ground point' for me. I see there is some pin labeled 'GND', but I don't know whether it's safe to treat that as the 'known ground point'.

Here are the pics:

http://www.cykerway.com/images/mr11u_front.png

http://www.cykerway.com/images/mr11u_back.png

BTW, it seems many TP-LINK routers follow the (TX, RX, GND, VCC) style, but I'm still not sure whether that applies to MR11U.

Update. After testing it with a multimeter, here's the result (but use at your own risk!) that may be helpful:

http://www.cykerway.com/images/mr11u_pins.png

Re: Serial port on TP-LINK MR11U

I was told in another message in this forum that its the P1 at the TP-Link letter in your first pic in the upper right corner

Re: Serial port on TP-LINK MR11U

kocoman wrote:

I was told in another message in this forum that its the P1 at the TP-Link letter in your first pic in the upper right corner

Thanks, I guess so as well. But what is the pin order?

4 (edited by staylo 2012-01-06 19:56:31)

Re: Serial port on TP-LINK MR11U

I'd work on the assumption that it's the same as other TP-LINK devices such as the WR1043ND
http://wiki.openwrt.org/toh/tp-link/tl-wr1043nd?s#serial

The GND test point should be usable.

Re: Serial port on TP-LINK MR11U

staylo wrote:

I'd work on the assumption that it's the same as other TP-LINK devices such as the WR1043ND
http://wiki.openwrt.org/toh/tp-link/tl-wr1043nd?s#serial

The GND test point should be usable.

Yeah, this's confirmed. I successfully debricked my MR11U using the serial port according to the order (TX, RX, GND, VCC) (only the first 3 are used). The point marked as GND is really GND, because when I looked at it from the back side, I suddenly realized it's the negative pole of the battery.

BTW, what's the VCC for? I hardly see it's used in any tutorial.

Re: Serial port on TP-LINK MR11U

This looks like the serial log
   

U-Boot 1.1.4 (Nov  3 2011 - 16:50:11)

AP121 (ar9330) U-boot

DRAM:  32 MB
led turning on for 1s...
id read 0x100000ff
flash size 4194304, sector count = 64
Flash:  4 MB
Using default environment

In:    serial
Out:   serial
Err:   serial
Net:   ag7240_enet_initialize...
No valid address in Flash. Using fixed address
No valid address in Flash. Using fixed address
: cfg1 0x5 cfg2 0x7114
eth0: 00:03:7f:09:0b:ad
ag7240_phy_setup 
eth0 up
: cfg1 0xf cfg2 0x7214
eth1: 00:03:7f:09:0b:ad
athrs26_reg_init_lan
ATHRS26: resetting s26
ATHRS26: s26 reset done
ag7240_phy_setup 
eth1 up
eth0, eth1
Autobooting in 1 seconds
## Booting image at 9f020000 ...
   Uncompressing Kernel Image ... OK

Starting kernel ...

Booting AR9330(Hornet)...
Linux version 2.6.31--LSDK-9.2.0.312 (root@bogon) (gcc version 4.3.3 (GCC) ) #202 Thu Nov 3 16:50:24 CST 2011
flash_size passed from bootloader = 4
CPU revision is: 00019374 (MIPS 24Kc)
Determined physical RAM map:
 memory: 02000000 @ 00000000 (usable)
User-defined physical RAM map:
 memory: 02000000 @ 00000000 (usable)
Zone PFN ranges:
  Normal   0x00000000 -> 0x00002000
Movable zone start PFN for each node
early_node_map[1] active PFN ranges
    0: 0x00000000 -> 0x00002000
Built 1 zonelists in Zone order, mobility grouping on.  Total pages: 8128
Kernel command line: console=ttyS0,115200 root=31:02 rootfstype=squashfs init=/sbin/init mtdparts=ar7240-nor0:128k(u-boot),1024k(kernel),2816(rootfs),64k(conM
PID hash table entries: 128 (order: 7, 512 bytes)
Dentry cache hash table entries: 4096 (order: 2, 16384 bytes)
Inode-cache hash table entries: 2048 (order: 1, 8192 bytes)
Primary instruction cache 64kB, VIPT, 4-way, linesize 32 bytes.
Primary data cache 32kB, 4-way, VIPT, cache aliases, linesize 32 bytes
Writing ErrCtl register=00000000
Readback ErrCtl register=00000000
Memory: 29864k/32768k available (1889k kernel code, 2904k reserved, 524k data, 116k init, 0k highmem)
Hierarchical RCU implementation.
NR_IRQS:128
plat_time_init: plat time init done
Calibrating delay loop... 266.24 BogoMIPS (lpj=532480)
Mount-cache hash table entries: 512
NET: Registered protocol family 16
===== ar7240_platform_init: 0
bio: create slab <bio-0> at 0
SCSI subsystem initialized
usbcore: registered new interface driver usbfs
usbcore: registered new interface driver hub
usbcore: registered new device driver usb
NET: Registered protocol family 2
IP route cache hash table entries: 1024 (order: 0, 4096 bytes)
TCP established hash table entries: 1024 (order: 1, 8192 bytes)
TCP bind hash table entries: 1024 (order: 0, 4096 bytes)
TCP: Hash tables configured (established 1024 bind 1024)
TCP reno registered
NET: Registered protocol family 1
AR7240 GPIOC major 0
squashfs: version 4.0 (2009/01/31) Phillip Lougher
NTFS driver 2.1.29 [Flags: R/O].
msgmni has been set to 58
alg: No test for lzma (lzma-generic)
alg: No test for stdrng (krng)
io scheduler noop registered
io scheduler anticipatory registered
io scheduler deadline registered
io scheduler cfq registered (default)
Serial: 8250/16550 driver, 1 ports, IRQ sharing disabled
ttyS0: detected caps 00000000 should be 00000100
serial8250.0: ttyS0 at MMIO 0xb8020000 (irq = 19) is a 16550A
console [ttyS0] enabled
PPP generic driver version 2.4.2
NET: Registered protocol family 24
cmdlinepart partition parsing not available
set partition boot 
set partition kernel 
set partition rootfs 
set partition config 
set partition art 
set partition � 
Searching for RedBoot partition table
5 RedBoot partitions found on MTD device ar7240-nor0
Creating 5 MTD partitions on "ar7240-nor0":
0x000000000000-0x000000020000 : "boot"
0x000000020000-0x000000120000 : "kernel"
0x000000120000-0x0000003e0000 : "rootfs"
0x0000003e0000-0x0000003f0000 : "config"
0x0000003f0000-0x000000400000 : "art"
->Oops: flash id 0x10215 . 
ehci_hcd: USB 2.0 'Enhanced' Host Controller (EHCI) Driver
Port Status 1c000004 
ar7240-ehci ar7240-ehci.0: ATH EHCI
ar7240-ehci ar7240-ehci.0: new USB bus registered, assigned bus number 1
ehci_reset Intialize USB CONTROLLER in host mode: 3
ehci_reset Port Status 1c000000 
ar7240-ehci ar7240-ehci.0: irq 3, io mem 0x1b000000
ehci_reset Intialize USB CONTROLLER in host mode: 3
ehci_reset Port Status 1c000000 
ar7240-ehci ar7240-ehci.0: USB 2.0 started, EHCI 1.00
usb usb1: configuration #1 chosen from 1 choice
hub 1-0:1.0: USB hub found
hub 1-0:1.0: 1 port detected
TCP cubic registered
NET: Registered protocol family 17
802.1Q VLAN Support v1.8 Ben Greear <greearb@candelatech.com>
All bugs added by David S. Miller <davem@redhat.com>
ar7240wdt_init: Registering WDT success
VFS: Mounted root (squashfs filesystem) readonly on device 31:2.
Freeing unused kernel memory: 116k freed
init started:  BusyBox v1.01 (2011.04.01-07:49+0000) multi-call binary
This Board use 2.6.31
xt_time: kernel timezone is -0000
nf_conntrack version 0.5.0 (512 buckets, 5120 max)
ip_tables: (C) 2000-2006 Netfilter Core Team
insmod: cannot open module `/lib/modules/2.6.31/kernel/iptable_raw.ko': No such file or directory
insmod: cannot open module `/lib/modules/2.6.31/kernel/flashid.ko': No such file or directory
PPPoL2TP kernel driver, V1.0
PPTP driver version 0.8.3
insmod: cannot open module `/lib/modules/2.6.31/kernel/harmony.ko': No such file or directory

Now flash open!
 (none) mips #202 Thu Nov 3 16:50:24 CST 2011 (none)
(none) login: Now flash open!
ATHR_GMAC: Length per segment 1536
ATHR_GMAC: fifo cfg 3 01f00140
ATHR_GMAC: Mac address for unit 1:bf1f0006
ATHR_GMAC: 63:e4:1a:56:1f:a8 
ATHR_GMAC: Max segments per packet :   1
ATHR_GMAC: Max tx descriptor count :   40
ATHR_GMAC: Max rx descriptor count :   96
ATHR_GMAC: Mac capability flags    :   4D83
ATHR_GMAC: Mac address for unit 0:bf1f0000
ATHR_GMAC: 02:92:85:0d:de:cb 
ATHR_GMAC: Max segments per packet :   1
ATHR_GMAC: Max tx descriptor count :   40
ATHR_GMAC: Max rx descriptor count :   252
ATHR_GMAC: Mac capability flags    :   4403
athr_gmac_ring_alloc Allocated 640 at 0x81e7d800
athr_gmac_ring_alloc Allocated 4032 at 0x81d63000
Setting Drop CRC Errors, Pause Frames and Length Error frames 
Setting PHY...mac 0
athr_gmac_ring_alloc Allocated 640 at 0x81e7d400
athr_gmac_ring_alloc Allocated 1536 at 0x81f21000
Setting Drop CRC Errors, Pause Frames and Length Error frames 
ATHRS26: resetting s26
ATHRS26: s26 reset done
Setting PHY...mac 1
device eth0 entered promiscuous mode
Now flash open!
nf_conntrack_rtsp v0.6.21 loading
nf_nat_rtsp v0.6.21 loading
asf: module license 'Proprietary' taints kernel.
Disabling lock debugging due to kernel taint
ath_hal: 0.9.17.1 (AR9380, DEBUG, REGOPS_FUNC, WRITE_EEPROM, 11D)
ath_rate_atheros: Copyright (c) 2001-2005 Atheros Communications, Inc, All Rights Reserved
ath_dev: Copyright (c) 2001-2007 Atheros Communications, Inc, All Rights Reserved
ath_ahb: 9.2.0_U5.508 (Atheros/multi-bss)
Boostrap clock 25MHz
ar9300RadioAttach: Need analog access recipe!!
Restoring Cal data from Flash
ath_get_caps[4735] rx chainmask mismatch actual 1 sc_chainmak 0
ath_get_caps[4710] tx chainmask mismatch actual 1 sc_chainmak 0
wifi0: Atheros 9380: mem=0xb8100000, irq=2
wlan_vap_create : enter. devhandle=0x80d182c0, opmode=IEEE80211_M_HOSTAP, flags=0x1
wlan_vap_create : exit. devhandle=0x80d182c0, opmode=IEEE80211_M_HOSTAP, flags=0x1.
VAP device ath0 created 
 
 DES SSID SET=TP-LINK_XXXXXX 
ieee80211_scan_unregister_event_handler: Failed to unregister evhandler=c0aea840 arg=81f642c0
wlan_vap_delete : enter. vaphandle=0x81e9c000
wlan_vap_delete : exit. vaphandle=0x81e9c000
wlan_vap_create : enter. devhandle=0x80d182c0, opmode=IEEE80211_M_HOSTAP, flags=0x1
wlan_vap_create : exit. devhandle=0x80d182c0, opmode=IEEE80211_M_HOSTAP, flags=0x1.
VAP device ath0 created 
 
 DES SSID SET=TP-LINK_XXXXXX 
 ieee80211_ioctl_siwmode: imr.ifm_active=393856, new mode=3, valid=1 
WARNING: Fragmentation with HT mode NOT ALLOWED!!
device ath0 entered promiscuous mode
br0: port 2(ath0) entering forwarding state
 ieee80211_ioctl_siwmode: imr.ifm_active=1442432, new mode=3, valid=1 
br0: port 2(ath0) entering disabled state
 
 DES SSID SET=TP-LINK_XXXXXX 
br0: port 2(ath0) entering forwarding state
ath_bstuck_tasklet: stuck beacon; resetting (bmiss count 9)
ath_bstuck_tasklet: stuck beacon; resetting (bmiss count 9)

 TL-MR11U mips #202 Thu Nov 3 16:50:24 CST 2011 (none)
TL-MR11U login: root
Password: 
Jan  1 00:01:13 login[150]: root login  on `ttyS0'



BusyBox v1.01 (2011.04.01-07:49+0000) Built-in shell (msh)
Enter 'help' for a list of built-in commands.

# cat /proc/mtd 
dev:    size   erasesize  name
mtd0: 00020000 00010000 "boot"
mtd1: 00100000 00010000 "kernel"
mtd2: 002c0000 00010000 "rootfs"
mtd3: 00010000 00010000 "config"
mtd4: 00010000 00010000 "art"
# cat /proc/meminfo 
MemTotal:          29980 kB
MemFree:           12536 kB
Buffers:            1944 kB
Cached:             6360 kB
SwapCached:            0 kB
Active:             3776 kB
Inactive:           6520 kB
Active(anon):       1992 kB
Inactive(anon):        0 kB
Active(file):       1784 kB
Inactive(file):     6520 kB
Unevictable:           0 kB
Mlocked:               0 kB
SwapTotal:             0 kB
SwapFree:              0 kB
Dirty:                 0 kB
Writeback:             0 kB
AnonPages:          2016 kB
Mapped:             1752 kB
Slab:               4488 kB
SReclaimable:        328 kB
SUnreclaim:         4160 kB
PageTables:          172 kB
NFS_Unstable:          0 kB
Bounce:                0 kB
WritebackTmp:          0 kB
CommitLimit:       14988 kB
Committed_AS:       4320 kB
VmallocTotal:    1048404 kB
VmallocUsed:        2132 kB
VmallocChunk:    1036936 kB
# iwconfig 
lo        no wireless extensions.

eth0      no wireless extensions.

eth1      no wireless extensions.

br0       no wireless extensions.

wifi0     no wireless extensions.

ath0      IEEE 802.11ng  ESSID:"TP-LINK_XXXXXX"  
          Mode:Master  Frequency:2.462 GHz  Access Point: 38:83:45:XX:XX:XX   
          Bit Rate:150 Mb/s   Tx-Power:7 dBm   
          RTS thr:off   Fragment thr:off
          Encryption key:off
          Power Management:off
          Link Quality=94/94  Signal level=-96 dBm  Noise level=-95 dBm
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0

# ifconfig 
ath0      Link encap:Ethernet  HWaddr 38:83:45:XX:XX:XX  
          UP BROADCAST RUNNING MULTICAST  MTU:2290  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:2 errors:0 dropped:41 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:0 (0.0 B)  TX bytes:752 (752.0 B)

br0       Link encap:Ethernet  HWaddr 38:83:45:XX:XX:XX  
          inet addr:192.168.1.1  Bcast:192.168.1.255  Mask:255.255.255.0
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1                                                     
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0                                                     
          TX packets:41 errors:0 dropped:0 overruns:0 carrier:0                                                  
          collisions:0 txqueuelen:0                                                                              
          RX bytes:0 (0.0 B)  TX bytes:14218 (13.8 KiB)                                                          
                                                                                                                 
eth0      Link encap:Ethernet  HWaddr 38:83:45:XX:XX:XX                                                          
          UP BROADCAST MULTICAST  MTU:1500  Metric:1                                                             
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0                                                     
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0                                                   
          collisions:0 txqueuelen:1000                                                                           
          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)                                                                 
                                                                                                                 
eth1      Link encap:Ethernet  HWaddr 38:83:45:XX:XX:XX                                                          
          inet addr:1.0.182.244  Bcast:1.255.255.255  Mask:255.0.0.0                                             
          UP BROADCAST MULTICAST  MTU:1500  Metric:1                                                             
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0                                                     
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0                                                   
          collisions:0 txqueuelen:1000                                                                           
          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)                                                                 
                                                                                                                 
lo        Link encap:Local Loopback                                                                              
          inet addr:127.0.0.1  Mask:255.0.0.0
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:63 errors:0 dropped:0 overruns:0 frame:0
          TX packets:63 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:5928 (5.7 KiB)  TX bytes:5928 (5.7 KiB)

wifi0     Link encap:Ethernet  HWaddr 38:83:45:XX:XX:XX  
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:1 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)
          Interrupt:2 Memory:b8100000-b811ffff 

# 
# cat /proc/version 
Linux version 2.6.31--LSDK-9.2.0.312 (root@bogon) (gcc version 4.3.3 (GCC) ) #202 Thu Nov 3 16:50:24 CST 2011