Now let's control the blue LED using code instead of Tinker. If you [[Spark.IO-Build|click here]] or on Build on the main page, you'll be in the IDE- where we can write code and upload it to the Core. Log in with the same email and password you used to sign up in the app, and we're off!
Click "BLINK AN LED" under the Example apps title. This code turns D7 (labeled ''led2'') on and off, once a second. Click the lightning bolt icon in the upper left and it will upload or "flash" this code onto your Core. You'll see a series of status colors on the main LED, and then the little blue LED blinking. Magic!
+
+
You can find more info in the [[Spark.IO-Build|Web IDE (Build) page]].