Electronic – Gibberish output from an ESP8622 WiFi module

esp8266ftdimicrocontrolleruart

Recently I've got myself a couple of ESP8266 modules. I flashed the latest NodeMCU firmware, and tried to communicate with a PC using UART.

Here's how I wired my circuit:
breadboard
schematic

Using a simple USB to Serial interface or FTDI I tried to communicate with the ESP8266 with ESPlorer v0.2.0. I opened a Port on baud 74880 because It's the only successful one for some reason.. Here's the log.

ets Jan 8 2013,rst cause:2, boot mode:(3,6)

is the only 'reasonable' output from the ESP8266, sometimes I get

Fatal exception(0):

from ESP8266 module but It's very rare.

I've been struggling with this for a good week now.
ESP8266 is very unpredictable to work with.. For every command I send I get garbage output or that ets Jan…

Any good ideas? Maybe the FTDI can't draw enough current?

Best Answer

You have two problems

1) The output you see (ets Jan 8 2013,rst cause:2, boot mode:(3,6)) is printed by the startup (bootloader) code. After that, the communication continues on a different baudrate (IIRC either 9600 or 115200 baud, depending on the firmware revision).

2) The 3.3V output of an FT232 can't deliver the current required by an ESP8266: not by a wide margin. Use a separate 3.3V supply. Probably the ESP8266 crashes due to too low voltage during or right after startup.