ESP8266 Community Forum

- Thu Jul 16, 2015 7:11 am #23411 Hello again,
Thank you for your help, kenn, but I can't even use the AP commands
I tried to upload 9.5 AT Firmware by AI-Thinker but when I try to upolad it with esptool, this is the problem I get:

Connecting...
Traceback (most recent call last):
File "./esptool.py", line 505, in <module>
esp.connect()
File "./esptool.py", line 158, in connect
raise Exception('Failed to connect')
Exception: Failed to connect

I also tried to swap the RX and TX again to make it normal, but the result was the same. The only connection I changed was GPIO0 to gnd, which was necessary for flashing... Any suggestions?
Again, thanks for your replies.

- Thu Jul 16, 2015 12:56 pm #23446 I don't use (or have) Arduinos so i can't be any help there, sorry.

when esptool says "Failed to connect", it means you failed to connect

Common reasons for not connecting when flashing:
- no connection
- USB to serial (or USB->Arduino->serial) isn't working
- something else is already on that serial connection (you must exit the terminal program before flashing)
- esptool - wrong com port selected. it defaults to COM0 i think, but you can set it with a param. See esptool.py docs and the source for more info.

if you still see serial output when restarting the ESP, you've probably solved #1 and 2, kill your terminal for #3, and finally check your settings for esptool.