on Received Number

Run part of a program when the micro:bit receives a number over radio.

radio.onReceivedNumber(function (receivedNumber) {})

Parameters

receivedNumber: The number that was sent in this packet or 0 if this packet did not contain a number. See send number and send value

Watch this video to see how the radio hardware works on the micro:bit:

Examples

Tell me how fast

This program keeps sending numbers that say how fast the micro:bit is slowing down or speeding up. It also receives numbers for the same thing from nearby micro:bits. It shows these numbers as a bar graph.

radio.setGroup(1)
basic.forever(() => {
    radio.sendNumber(input.acceleration(Dimension.X));
})
radio.onReceivedNumber(function (receivedNumber) {
    led.plotBarGraph(receivedNumber, 1023);
})

What’s the distance?

This program uses the signal strength from received packets to graph the approximate distance between two micro:bits.

radio.setGroup(1)
basic.forever(() => {
    radio.sendNumber(0)
})
radio.onReceivedNumber(function (receivedNumber) {
    led.plotBarGraph(
        Math.abs(radio.receivedPacket(RadioPacketProperty.SignalStrength) + 42),
        128 - 42
    )
})

Troubleshooting

The ||radio:onReceivedNumber|| event can only be created once, due to the hardware restrictions.

The radio set group might need to be set, synchronized, before the radio events will function.