pxt-calliope/docs/reference/radio/receive-number.md

Receive Number

Receives the next number sent by a micro:bit in the same radio group.

radio.receiveNumber();

Returns

• the first number that the micro:bit received. If it did not receive any numbers, this function will return 0.

Simulator

This function only works on the micro:bit, not in browsers.

Example: Simple number receiver

This example receives the number broadcasted another micro:bit and shows it as a bar graph.

radio.onDataReceived(() => {
    led.plotBarGraph(radio.receiveNumber(), 1023);
})

Example: Light level receiver

This example shows the light level from the light level sender example as a number.

radio.setGroup(99)
basic.forever(() => {
    let level = radio.receiveNumber()
    basic.showNumber(level)
})

Example: Mailbot

This example receives the light level from the light level sender example and shows a text string like ALERT if the light level becomes much brighter. To find when the mail arrives, you can put the light level sender in your mailbox and it will tell you when someone opens the box. You can try this with a normal box too, like a present for a friend.

radio.setGroup(99)
let max = 0
basic.forever(() => {
    let level = radio.receiveNumber()
    if (level > max) {
        max = level
    }
    if (max > 10) {
        basic.showString("ALERT")
    }
})

See also

send number, on data received

radio