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Topic: plz help serial communication rs232

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Hi all,

I have tl-wr941nd v3.7 I tried to install Backfire 10.03.1 firmware as stated on the website but some after the reboot I can't ping only the power LED is on ...  the only way is serial connection so I connected  CA-42 Clone Cable  to the board and didn't detected by win7 as there is no driver after I used Ubuntu and minicom to connect I did all the setting everything is ok but what I am doing wrong I can't connect to TP !!!!


please help me to save it even with easy steps ... do I need to turn the power on when the USB is connected or what  ... please explain ...


Thank you

I've managed to access uboot


U-Boot 1.1.4 (Jan 30 2012 - 17:57:33)                                           
                                                                                
AP81 (ar7100) U-boot                                                            
DRAM:                                                                           
sri                                                                             
32 MB                                                                           
id read 0x100000ff                                                              
flash size 4MB, sector count = 64                                               
Flash:  4 MB                                                                    
Using default environment                                                       
                                                                                
In:    serial                                                                   
Out:   serial                                                                   
Err:   serial                                                                   
Net:   ag7100_enet_initialize...                                                
No valid address in Flash. Using fixed address                                  
bsingle_phy = 0                                                                 
eth0: 00:03:7f:09:0b:ad                                                         
eth0 up                                                                         
eth0                                                                            
Autobooting in 1 seconds## Booting image at bf020000 ...                        
   Uncompressing Kernel Image ... OK                                            
                                                                                
Starting kernel ...                                                             
                                                                                
Linux version 2.6.32.27 (jow@nd-build-02.linux-appliance.net) (gcc version 4.3.1
bootconsole [early0] enabled                                                    
CPU revision is: 00019374 (MIPS 24Kc)                                           
Atheros AR9132 rev 2, CPU:400.000 MHz, AHB:100.000 MHz, DDR:400.000 MHz         
Determined physical RAM map:                                                    
 memory: 02000000 @ 00000000 (usable)                                           
Initrd not found or empty - disabling initrd                                    
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: rootfstype=squashfs,yaffs,jffs2 noinitrd console=ttyS0,115D
PID hash table entries: 128 (order: -3, 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: 29276k/32768k available (2126k kernel code, 3492k reserved, 423k data, )
SLUB: Genslabs=7, HWalign=32, Order=0-3, MinObjects=0, CPUs=1, Nodes=1          
Hierarchical RCU implementation.                                                
NR_IRQS:56                                                                      
Calibrating delay loop... 266.24 BogoMIPS (lpj=1331200)                         
Mount-cache hash table entries: 512                                             
NET: Registered protocol family 16                                              
MIPS: machine is TP-LINK TL-WR941ND                                             
bio: create slab <bio-0> at 0                                                   
Switching to clocksource MIPS                                                   
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                                               
squashfs: version 4.0 (2009/01/31) Phillip Lougher                              
Registering mini_fo version $Id$                                                
JFFS2 version 2.2. (NAND) (SUMMARY)  �© 2001-2006 Red Hat, Inc.                 
yaffs Dec 10 2011 18:14:12 Installing.                                          
msgmni has been set to 57                                                       
io scheduler noop registered                                                    
io scheduler deadline registered (default)                                      
Serial: 8250/16550 driver, 1 ports, IRQ sharing disabled                        
serial8250.0: ttyS0 at MMIO 0x18020000 (irq = 11) is a 16550A                   
console [ttyS0] enabled, bootconsole disabled                                   
console [ttyS0] enabled, bootconsole disabled                                   
Atheros AR71xx SPI Controller driver version 0.2.4                              
m25p80 spi0.0: unrecognized JEDEC id 1c3016                                     
ag71xx_mdio: probed                                                             
eth0: Atheros AG71xx at 0xb9000000, irq 4                                       
Atheros AR71xx hardware watchdog driver version 0.1.0                           
TCP westwood registered                                                         
NET: Registered protocol family 17                                              
Distributed Switch Architecture driver version 0.1                              
ar7240_dsa: unsupported chip, ctrl=ffffffff                                     
eth0[0]: detected a Marvell 88E6060 switch                                      
dsa slave smi: probed                                                           
802.1Q VLAN Support v1.8 Ben Greear <greearb@candelatech.com>                   
All bugs added by David S. Miller <davem@redhat.com>                            
VFS: Cannot open root device "<NULL>" or unknown-block(0,0)                     
Please append a correct "root=" boot option; here are the available partitions: 
Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0)  

what is the problem ?

(Last edited by testooo on 1 Jul 2013, 04:08)

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