Coding the Dandelion

Concepts:

• Sensors (Sound)
• Pixels
• Brightness

Duration: 20 minutes

Blocks

light.setAll(0xffff00)
light.setBrightness(input.soundLevel())

Step 1: Turn the lights on

Open https://makecode.adafruit.com/ in your web browser.

forever(() => {
    light.setAll(0xffff00)
})

From LIGHT, drag a set all pixels block, and place it inside a forever loop.

Change the current color to one that you like. I chose yellow for my dandelion!

Connect your Adafruit Circuit Playground Express to your computer’s USB port and click Download. Follow the instructions to move the code to your Adafruit Circuit Playground Express.

Step 2: Set the brightness

input.buttonA.onEvent(ButtonEvent.Click, () => {
    light.setBrightness(100)
    light.setAll(0xffff00)
})
input.buttonB.onEvent(ButtonEvent.Click, () => {
    light.setBrightness(255)
    light.setAll(0xffff00)
})

Build the blocks

• From INPUT drag an on button click block into the coding area
• From LIGHT drag a set brightness block into the on button click block
• Move the set all block so it’s just after the set brightness block in the on button click block
• Set the brightness to 100

Do the same for the B button, and set the brightness to 255 when the B button is clicked

• Download the code to your Adafruit Circuit Playground Express and try pressing the A & B buttons

Step 3: Use the sound sensor

The sound level block reports the current sound level, a value between 0 and 255.

The set brightness block sets the brightness of pixels, and takes as a input a value between 0 and 255.

Let’s try and set the brightness of the pixels to the current sound level.

forever(() => {
    light.setBrightness(input.soundLevel())
    light.setAll(0xffff00)
})

Build the blocks

• From LIGHT drag a set brightness block and place it at the top of the forever loop
• From INPUT drag a sound level block and place it as the input of the set brightness block

Download the code to your Adafruit Circuit Playground Express and try to blow on it.

Good work!

Challenge: Use some of the other sensor blocks (under INPUT) to change the brightness based on these sensor values (optional).