ESP8266 Community Forum

Hi

I had a fully working ESP-01 with the default AT firmware.

I attempted to flash the LUA firmware using https://github.com/nodemcu/nodemcu-flasher and flashed nodemcu_latest.bin from here https://github.com/nodemcu/nodemcu-firm ... uild/0.9.5

I set the flasher up exactly like the screenshot on the flasher github site. I went to the Config tab and typeed in c:\nodemcu_latest.bin. I then unticked the other 3 boxes. I also set the speed to 9600 as thats the speed I use to communicate with the ESP (probably my mistake). The bar went across and seemed to flash ok.

Now after letting GPIO0 float I cant get anything out of the ESP. the blue light does not flash at all when its powered up. I have tried reflashing but nothing happens I think I killed it

I have 1 ESP left that I have confirmed my setup works with.

Is there any way of recovering the ESP or is it just a goner?

Check the resistance of the LED resistor.
http://rayshobby.net/?p=10241

Make sure you don't have any extra wires pulled low or high. Try reflashing the firmware and see if it lets you.

Double check the connections from ESP-01. GPIO0 has to be high, so has GPIO2 (you could leave them floating - they are pulled high when booting - or connect them via a 10k resistor to Vcc=3V3). You should/ could also do this with the reset (RST) pin. Let RX and TX float (unocnnected) and connect VCC to 3V3 and GND to GND. Start again and it should work if the flash did run to 100%.
Data speed in flash mode is autonegotiated (imho to 115.2k) and so the settings in the flash program are not important.

markbee

I have been building a little proto board so I can just plus in the esp-01 then I can't go wrong with the connections. I Will add a switch to pull both goto ports up. The board also has level shifting to the esp's RX I have been connecting directly from the ttl maybe the 5v has fried it over time.