Chat here is you are connecting ESP-xx type modules to existing AVR based Arduino

Moderator: igrr

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By lorensiuswlt
#69868 Hello fellows..

I'm new to esp8266 and arduino and now working on my iot project. I have problem on flashing nodemcu firmware into esp8266-01 wifi module. I use to flash but before flashing i tried to get my device id, so i use this command from command line (i use MacOS).

$sudo --port /dev/cu.usbmodem1421 flash_id

This command returns v2.1

A fatal error occurred: Failed to connect to Espressif device: Timed out waiting for packet header

My configuration as follows:


Mac to Arduino using USB cable. I use arduino uno as usb serial ttl (empty sketch).

ESP8266 - Arduino

GND <-> GND (black)
VCC <-> 3.3v (red)
GPIO0 <-> GND (purple)
GPIO2 <-> 3.3v (orange)
CH_PD <-> 3.3v (pink)
TX <-> TX (via logic level shifter) (yellow)
RX <-> RX (green)

The esp module works normally in normal mode (Esp GIPO0 ->3.3v), i can run AT commands and connect to access point. But if change the GPIO0 to GND in flash mode, i get no response in serial terminal and also the returns reponse time out.

Is anything wrong with my configuration? sorry i'm new to this, need your help. thank you.
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By schufti
#69883 your problem: the µC on Arduino Uno R3 and ESP-01 both want to talk on the same line.
Either remove the Atmel328 from the board or hold it in reset.

Do yourself a favour and spend the 2bucks for an ESP-01 flasher.