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Hi i have bricked TL-WR740N v4.23 (only power led is on after connecting power cord). According to this page:
http://wiki.openwrt.org/toh/tp-link/tl- … t.on.v4.23
I need to solder serial cable yes? But i really need to use USB to UART TTL converter? Or maybe i can use standard USB cable or eg COM Cable? (eg SE COM cable http://pinouts.ru/CellularPhones-P-W/er … nout.shtml [pins 4,5,10,11]).
Cheers
If you are going the serial router, make sure the usb->serial is 3v3, not higher. I can't see in the link you gave whether the phone cable is 3v3 or 5v.
But before you do that have you tried via failsafe (with ethernet connection):
For the (box branded) WR740N v2.4 and v4.23 the below works for recovery from nasty stuff like dropbear lockout, mtd overlay size problems or other software misuses :
Unplug the router's power cord.
Connect any router LAN port directly to your PC.
Configure your PC with a static IP address: 192.168.1.2
Plug the power on to the router.
Wait until the "SYS" LED starts flashing repeatedly.
Press the "QSS" button (on the front/back of the router) → the "SYS" LED will now start flashing at a faster rate.
Login to the router by using telnet to connect to the IP address 192.168.1.1 → there will be an immediate unauthenticated login to a root shell.If you are going the serial router, make sure the usb->serial is 3v3, not higher. I can't see in the link you gave whether the phone cable is 3v3 or 5v.
But before you do that have you tried via failsafe (with ethernet connection):
For the (box branded) WR740N v2.4 and v4.23 the below works for recovery from nasty stuff like dropbear lockout, mtd overlay size problems or other software misuses : Unplug the router's power cord. Connect any router LAN port directly to your PC. Configure your PC with a static IP address: 192.168.1.2 Plug the power on to the router. Wait until the "SYS" LED starts flashing repeatedly. Press the "QSS" button (on the front/back of the router) → the "SYS" LED will now start flashing at a faster rate. Login to the router by using telnet to connect to the IP address 192.168.1.1 → there will be an immediate unauthenticated login to a root shell.
Thanks for reply 
Failsafe doesn't work - after plugiing power cable only power led is on (not blinking). So theoretically i can use this phone cable but i need to solder from somewhere +3,3V?
NO. You have to confirm that the cable Tx/Rx are providing/accepting 3V3. There must be a data sheet somewhere. If they are, then you only need connect Tx, Rx and GND. If they work on higher voltage you might fry the serial lines.
DO NOT connect Vcc (any) to the router.
Ok thanks for clarification Last question - what about with cables from Nokia? DKU5/CA42? Can i use those cables?
sure!
if you need a guide:
http://buffalo.nas-central.org/index.ph … inkstation
steps are identical exept for the device-specific pinout...
(Last edited by nebbia88 on 12 May 2013, 15:24)
hey i have question. can i use a computer PSU to get 3.3V VCC????? And connect TX, RX and GND from USB cable?
(Last edited by damossq on 1 Nov 2013, 14:42)
you never have to connect VCC at all.
the router must have its own ac adapter and that is the only psu it needs.
(Last edited by nebbia88 on 1 Nov 2013, 14:50)
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