This simple library will connect the ESP8266 to a wifi network for you and while it's attempting connection, accept new credentials via the serial interface.

If you are not using EEPROM for anything else, the simplest method is as follows:

Download the library:

• Clone the project to your libraries folder (example for default OSX setup)

cd ~/Documents/Arduino/libraries
git clone https://github.com/loneconspirator/WifiCreds.git

In your sketch (example starting sketch file below):

• Include the library #include <WifiCreds.h>

• declare the object, optionally providing default credentials WifiCreds wifi() or WifiCreds wifi("ssid", "password")

Then, in your setup() function:

• Open your Serial connection (must be done before connecting)

• Connect to wifi wifi.connect() or, send an LED pin for output that you're trying to connect wifi.connect(LED_PIN)

To send in new credentials, just send a string in on the Serial connection with the ssid and password separated by a space while it's trying to connect

After this, the WiFi global object will be set up and available.

If you want to have a button input that will cancel the attempt to connect, that can be achieved with an interrupt that calls wifi.disable_wifi()

In your sketch:

void button() {
  if (wifi.is_wifi_enabled() && !wifi.is_connected())
  wifi.disable_wifi();
}

and in setup():

pinMode(BUTTON_PIN, INPUT_PULLUP);
attachInterrupt(digitalPinToInterrupt(BUTTON_PIN), button, FALLING);

If you need to use the EEPROM for other things, before connect(), you can call init_eeprom(eepromInit, offset).

eepromInit will be the value sent to EEPROM.begin (send 0 if you initialize the EEPROM on your own) offset is how many bytes to offest our use of the eeprom. This is 0 by default. WifiCreds takes 128 bytes of EEPROM

Here's an example file you can start with once the library is installed (I haven't tested this so there might be a glitch to two)

/**
 * ESP8266 IoT program
 * 
 */


#include <WifiCreds.h>

#include <ESP8266WiFi.h>

WifiCreds wifi("officenomads", "PinkyX");

// This is the pin of the blue LED on the huzzah which is for some reason backwards
#define IND_PIN 2 // output pin with LED indicating Wifi is connecting
#define BUTTON_PIN 4 // button that when connected to ground skips connecting to internet

void button() {
  if (wifi.is_wifi_enabled() && !wifi.is_connected())
    wifi.disable_wifi();
}

// the setup function runs once when you press reset or power the board
void setup() {
  // initialize pins
  pinMode(IND_PIN, OUTPUT);
  pinMode(BUTTON_PIN, INPUT_PULLUP);

  attachInterrupt(digitalPinToInterrupt(BUTTON_PIN), button, FALLING);

  Serial.begin(115200); while(!Serial) ; // Open Serial connection and wait for it to be good

  wifi.connect(IND_PIN);

  if (wifi.is_wifi_enabled()) {
    IPAddress ip = WiFi.localIP();
    Serial.print("IP Address: ");
    Serial.println(ip);
  }
}

void loop() {
  // put your main code here, to run repeatedly:

}