I recently ordered up a few of those super-cheap ESP8266 wifi modules. These have an 80211 b/g/n Wifi with WPA/WPA2 support, are super small and have a fairly powerful CPU on board (more powerful than that Arduino I am hooking it up to). I ordered my modules from Electrodragon and they came super-fast (and even shipped from state-side). For ~ $25.00 I got 4 pieces shipped to my door. In hindsight I should have ordered a couple of the modules with all the GPIO pins exposed. The first order of business is interfacing. These modules utilize a 3.3V power supply and IOs. I utilized my $17.00 Arduino Mega with 3.3v selector to be voltage compatible instead of setting up voltage dividers.
There are 5 critical pins needed to get this working:
- GND – Connect to Arduino GND
- VCC – Connect to Arduino 3.3V VDD
- UTXD – Connect to Arduino Mega RX1
- URXD – Connect to Arduino Mega TX1
- CH_PD – Connect to Arduino 3.3V VDD