http://www.esp8266.com/wiki/doku.php seems to be a good starting place with a lot of interesting information. Also very extensive documentation can be found in Neil Kolban’s ESP8266 Book (pretty large PDF).
- red: +5V ?
- black: GND
- white: TXD 3.3V
- green: RXD
Attention: The breakout boards I got came with an unmounted voltage regulator IC. I had to remove the resistor bridge in order to use the regulator.
Connection of the serial cable to the breakoutboard:
- red -> VCC
- black -> GND
- white -> RXD (!)
- green -> TXD
Plugging the converter into the USB plug at the PC.
shows that the converter is detected.
minicom -D /dev/ttyUSB0
With baudrate 115200 I can issue AT commands after terminating them with CTRL-M CTRL-J and get the proper response.
At least in Minicom CTRL-M can be replaced by the RETURN key.
The commands need to be in upper case.
I will quit the step “connecting to my wifi” and continue directly with “uploading new firmware”.