pxt-calliope/docs/projects/soil-moisture/connect.md
Peli de Halleux 676eee168a Soil - moisture ()
* updated servo calibrator

* updated plot analog pin example

* updated servo example

* first drop of soil moisture

* updated picture

* fixing macros

* update code section

* 5 seconds

* adding soil moisture

* fixing links
2017-06-21 11:17:25 -07:00

1.4 KiB

Connect

We are going to use radio to send the current moisture level to a dashboard @boardname@. The dashboard will display one LED per @boardname@.

Moisture sensor

To make it happen, we need to change the program to

  • setup the radio by choosing group 4 and sending the serial number of the device
  • send the moisture level divided by 4 as the dashboard takes values between 0 and 255.
radio.setTransmitSerialNumber(true)
radio.setGroup(4)
led.setBrightness(64)
let reading = 0
basic.forever(() => {
    pins.analogWritePin(AnalogPin.P1, 1023)
    reading = pins.analogReadPin(AnalogPin.P0)
    radio.sendNumber(reading / 4);
    pins.analogWritePin(AnalogPin.P1, 0)
    led.plotBarGraph(
        reading,
        1023
    )
    if (input.buttonIsPressed(Button.A)) {
        basic.showNumber(reading)
    }
    basic.pause(5000);
})

The dashboard

The dashboard code can be found at /examples/radio-dashboard.

Download the code from that example into the @boardname@ that will be used to display the result.

When the dashboard receives a message from a @boardname@, it find a pixel for that board (and remembers it) and uses the number received as the brightness of the LED.

When a message hasn't been received by a board for some time, it's pixel will start to blink. After more time, it will simply turn off.

radio