pxt-calliope/docs/reference/radio/on-data-packet-received.md
2016-11-01 17:44:37 -07:00

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# On Data Packet Received
Run part of a program when the @boardname@ receives a
[number](/reference/types/number) or [string](/reference/types/string) over ``radio``.
```sig
radio.onDataPacketReceived(({receivedNumber, receivedString, time, serial, signal}) => { });
```
### ~hint
To add or remove the parts of the packet from the block, try clicking the blue gear in the corner!
### ~
### Callback Parameters
* ``packet`` - the [packet](/reference/radio/packet) that was received by the radio. The packet has the following properties:
* `receivedNumber` - The [number](/reference/types/number) that was sent in this packet or `0` if this packet did not contain a number. See [send number](/reference/radio/send-number) and [send value](/reference/radio/send-value)
* `receivedString` - The [string](/reference/types/string) that was sent in this packet or the empty string if this packet did not contain a string. See [send string](/reference/radio/send-string) and [send value](/reference/radio/send-value)
* `time` - The system time of the @boardname@ that sent this packet at the time the packet was sent.
* `serial` - The serial number of the @boardname@ that sent this packet or `0` if the @boardname@ did not include its serial number.
* `signal` - How strong the radio signal is from `255` (weak) to `0` (strong).
### Example
This program keeps sending numbers that says how fast the @boardname@ is
slowing down or speeding up. It also receives numbers for the same
thing from nearby @boardname@s. It shows these numbers as a
[bar graph](/reference/led/plot-bar-graph).
```blocks
basic.forever(() => {
radio.sendNumber(input.acceleration(Dimension.X));
})
radio.onDataPacketReceived(({ receivedNumber }) => {
led.plotBarGraph(receivedNumber, 1023);
})
```
### See also
[send number](/reference/radio/send-number),
[send string](/reference/radio/send-string),
[send value](/reference/radio/send-value),
[set group](/reference/radio/set-group)
```package
radio
```