I was looking for a transformer from 230v to 5v. Although I found multiple options, the price per unit seemed a little too expensive about €3.00. While that does not look too expensive per unit, remember we also need a switch and an ESP module for WiFi connectivity. So, as an alternative I looked into these Sonoff devices.
After learning that these are powered by ESP8266, I knew I can flash them to a custom firmware to get rid of the more complex software pre-installed (Chinese firmware).
So, the SonOff cost me €4.55 with free postage from our friends in China.
The first thing I always do when purchasing from China is to flash the firmware. I don’t know what is pre-installed and well I prefer to have more control.
- Download new firmware from https://nodemcu-build.com/.
- Upload firmware
- Upload code as normal via Arduino IDE
Remember you will need to solder those pins, I prefer a pin head
The four serial pins (3V3, Rx, Tx, GND, GPIO 14).
Looks like i may end up sticking with the Sonoff with my own coded software.