> For the complete documentation index, see [llms.txt](https://royals6234.gitbook.io/madmachine-examples/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://royals6234.gitbook.io/madmachine-examples/examples/makerkit/mission01blink.md).

# Mission 01 Blink

## What you need

## Circuit

## Tips

## Code

```swift
/*
  Mission1 Blink RGB LED

  The blue LED will flash on for 1 second, then off for 1 second.

  The circuit:
  - Use the onboard RGB LED.
  - Note: SwiftIO have an on-board RGB LED you can control.
    The onboard LED will be on when the value is set to false.

  created 2019
  by Orange J

  Try to change the RGB Led’s color to Red, Green, and Blue. 
  Add a blinking loop and see what will happen. This example code is in the 
  public domain. Visit madmachine.io for more info.
*/

import SwiftIO


// initialize the blue LED
let led = DigitalOut(Id.BLUE)

while true {
     // The code here will run all the time.

     // Set Blue LED off
     led.write(true)
     sleep(ms: 1000)    // Interval of LED blink (milliseconds)

     // Set Blue LED on
     led.write(false)
     sleep(ms: 1000)
}
```

## Video

## See Also

## References

Last revision 2020/09/10 by Johnson