ESP8266 Community Forum

- Sun Jan 31, 2016 6:17 pm #40126 So this may not be the correct place to ask this, but I can't flash my ESP8266 (ESP-01). I have 3.3v and ground connected, Rx to Tx and Tx to Rx on my usb to serial adaptor. I also have GPIO0 connected to ground too.

I am using an external power supply but the usb adaptor and power adaptor share a common ground.

I'm using a mac and esp tools to flash it, and it has worked before.
The command I am using is:

Code: Select allsudo ./esptool.py --port /dev/tty.wchusbserial1410 write_flash 0x00000 AT22SDK10020150320boot12.bin

But the response is:

Code: Select allA fatal error occurred: Failed to connect to ESP8266

This make me think something is wrong with receiving data from the ESP because when attempting to connect, the ESPs blue LED flashes.

My usb to serial adaptor works fine though as i've tested it with my arduino.

- Mon Feb 01, 2016 6:05 am #40147 GPIO2?

- Mon Feb 01, 2016 6:06 am #40148 I've flashed it before whilst not having GPIO2 connected to anything, what should I connect it to?

- Mon Feb 01, 2016 6:49 am #40152 Same problem with mine esp-01 1M black with serial FDTI . It's not flashing. All connection is ok, but end of the flash is giving "......................." uploading ...............bin file 0x000000 . And also I have to close with OK button. Than when I test it unground GPIO0 from GND blue led is lighting allways.