For a hobby project with my Arduino, i tried to use Johnny-Five. Because i wanted to use Kotlin, i created some KotlinJs wrapper.

The wrappers are not 100% complete, because i can't test all components. These are some components that i tried:

• Piezo
• Servo
• Led
• Button

When you have ideas for improvements, please write a GitHub issue.

1. Prepare your Board

   You need to install StandardFirmataPlus firmware to your board.

   Check the johnny-five documentation for more information

   Here is the instruction for Arduino:

   • Install and open Arduino IDE
   • Verify correct port and board
   • Navigate to File > Examples > Firmata > StandardFirmataPlus
   • Load sketch onto board.
   • If the upload was successful, the board is now prepared and you can close the Arduino IDE.

2. Create a new KotlinJS Project with NodeJs

kotlin {
   js(IR) {
         binaries.executable()
         nodejs {}
       }
   
       sourceSets {
           val jsMain by getting {
               dependencies {
                   implementation("de.jensklingenberg.kotlin-wrappers:johnny-five:0.8.3")
               }
           }
       }
   }
}

You also need to add this to your build.gradle.kts, otherwise you will get compile errors: "Error: Could not locate the bindings file"

rootProject.plugins.withType<org.jetbrains.kotlin.gradle.targets.js.yarn.YarnPlugin> {
rootProject.the<org.jetbrains.kotlin.gradle.targets.js.yarn.YarnRootExtension>().ignoreScripts = false
}

3. Create a new Kotlin file and write your code

fun main() {
   val LED_BUILTIN = 13
   val board = Board()

   board.onReady {
      println("READY")
      val led = Led(LED_BUILTIN)

      led.blink()

      onExit {
         println("EXIT")
         led.off()
      }
   }
}

4. You can then run build to compile the code

./gradlew build

5. You will find the compiled code in your build folder e.g. for the demo (https://github.com/Foso/JohnnyFiveKotlinWrapper/tree/main/demo) project it would be ./build/compileSync/js/main/productionExecutable/kotlin/demo

Use Node to run the compiled code:

node ./build/compileSync/js/main/productionExecutable/kotlin/demo

You should see something like this in your terminal:

• wrapper - contains the KotlinJs wrappers for johnny-five
• demo - Demo project using johnny-five with Kotlin/JS