95 lines
2.0 KiB
Markdown
95 lines
2.0 KiB
Markdown
# Receive String
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Find the next string sent by `radio` from another micro:bit.
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```sig
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radio.receiveString()
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```
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### Returns
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* the first [string](/reference/types/string) that was sent. If no
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string was sent, then this function returns an empty (blank) string.
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### Simulator
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This function only works on the micro:bit, not in browsers.
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### Example: Simple receiver
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Show the string sent by another micro:bit.
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```blocks
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radio.onDataReceived(() => {
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basic.showString(radio.receiveString());
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});
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```
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### Example: Two-way radio
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If you load this program onto two or more micro:bits, you can send a code word from one of them to the others by pressing button `A`.
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The other micro:bits will receive the code word and then show it.
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```blocks
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input.onButtonPressed(Button.A, () => {
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radio.sendString("Codeword: TRIMARAN")
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basic.showString("SENT");
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})
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radio.onDataReceived(() => {
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basic.showString(radio.receiveString());
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});
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```
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### ~hint
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A radio that can both transmit and receive is called a _transceiver_.
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### ~
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### Example: Mood radio
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This is a simple program to send whether you are happy or sad over ```radio```.
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Use the `A` or `B` button to select an emotion.
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This program will also receive your friend's mood.
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```blocks
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let data: string = "";
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input.onButtonPressed(Button.A, () => {
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radio.sendString("H");
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});
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input.onButtonPressed(Button.B, () => {
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radio.sendString("S");
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});
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radio.onDataReceived(() => {
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data = radio.receiveString();
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if ("H" == data) {
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basic.showLeds(`
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. . . . .
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. # . # .
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. . . . .
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# . . . #
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. # # # .
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`);
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} else if ("S" == data) {
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basic.showLeds(`
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. . . . .
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. # . # .
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. . . . .
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. # # # .
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# . . . #
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`);
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} else {
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basic.showString("?");
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}
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});
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```
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### See also
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[send string](/reference/radio/send-string), [on data received](/reference/radio/on-data-received)
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```package
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radio
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``` |