Migrate docs from the other repo

docs/reference/devices/receive-number.md

@@ -0,0 +1,42 @@
+# Receive Number
+
+The broadcast function. #docs #ble #radio
+
+Reads the next radio packet as a number data packet.
+
+## Important Security Consideration
+
+The functions in the ``radio`` namespace allow the BBC micro:bit to communicate with other micro:bits.
+
+This API does not contain any form of encryption, authentication or authorization. It's purpose is solely for use as a teaching aid to demonstrate how simple communications operates, and to provide a sandpit through which learning can take place.
+
+For serious applications, BLE should be considered a substantially more secure alternative.
+
+### Block Editor
+
+![](/static/mb/receive-number-0.png)
+
+### KindScript
+
+```
+export function receiveNumber() : number
+```
+
+### Returns
+
+* packet - a number received.
+
+### Examples
+
+Broadcasts the value of ``acceleration`` x to other micro:bits.
+
+```
+radio.onDataReceived(() => {
+    led.plotBarGraph(radio.receiveNumber(), 1023)
+})
+```
+
+### See also
+
+[send number](/microbit/reference/radio/send-number), [receive number](/microbit/reference/radio/receive-number), [on data received](/microbit/reference/radio/on-data-received), [set group](/microbit/reference/radio/set-group)
+