While trying to load original firmware on my TP-Link WA-701ND, I got the error "cannot erase the block" error and then I restarted the access point (not knowing that this is a no-no thing). Obviously, my access point got bricked after this faulty move. After power-on, power light is switched on. After couple of milliseconds (500 to 1000, I haven't measured the exact timing), all LEDs are turned on, then only power LED is on (this loop goes on and on...).  Although ethernet cable is plugged to the device and to the computer, computer does not recognize the connection.

Now I am trying to restore original firmware on this device. I found that TFTP & UART connection does wonders on this device. I had a cheap Chinese USB-TO-UART (RS232 in TTL voltage levels) converter based on chip CH340G, unfortunately without 3.3V-5V switch. I thought that giving it a go was a coherent idea.

After connecting with UART, adjusting all settings correctly (this includes things like baud rate and parity) I get some output but unfortunately it is consisting of random characters. I tried with two programs (termite and putty) results are same. When I removed the connections and only connected rx to tx to check the conversion module, I successfully read what I have written. Although receiving from access point does not work, When I write "tpl" from the console, this loop stops and nothing is printed out from UART. Computer recognizes that ethernet cable is connected.

I need exact guide for this device starting from here.

PS: Output from AP, I tried inverting bits but it didnt work either.
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(Last edited by murdertrk on 10 Jun 2016, 00:14)

Have you tried any other baud rates?

you need to connect ground also. Rx, Tx and Ground.

Yes, yes I connected ground as well. I am quite familiar with UART process because I am an Electrical and Electronics Engineering Student. That's why I had no trouble finding the required components & modules

Moreover, I mentioned that writing "tpl" resulted in an expected behaviour.

On the other hand, I doubt that lack of a level shifting circuitry might be the reason. Tomorrow, I am going to try with my bi-directional level shifter circuit (it was for I2C protocol but I am quite sure it will work with UART).

This baud rate (115200) was written at wiki, both for this AP and for other products of TP-Link.
In addition to this, TX to modem perfectly works, so problem is most likely due to a specific condition regarding RX from modem.

(Last edited by murdertrk on 10 Jun 2016, 00:08)

The first test is always to get RX from device "running"
Without connecting TX !!!
If you see a good readable output the baudrate is OK.

Then connect TX.
Important :
If you don't use a level shifter for TX you will damage your board permanently.

Don't use bi-directional level shifters for this.

Hello after an unintended long break (due to health issues)

The problem here is, baud rate is correct, 115.2kbps for the modem and TX works correctly. I even managed to send commands for TFTP requests. Only problem is RX from AP. I cannot receive readable data from AP.

The thing is, reading what my modem says is not cruical. I only want to restore a firmware, regardless it is default or OpenWrt.

This issue is still not solved, so I am waiting for your help.

Have a good day!

i have facing a problem with wa701nd device, when i was assigned this device as clint mode after rebooting it shows it is in access point mode, but other changes made correctly like network ip, ssid, password etc. then i upgraded its firmware, after succesfull installation of upgrading firmware the device is rebooted, then i was faced this critical problem it is not showing lan connectivity between device to pc, i want my device back  as perfect, please direct me how to get that back as working device. on the device it shows only single power light, reset button also not responding while press and hold.