pxt-calliope/docs/reference/input/pin-is-pressed.md
2016-06-08 18:14:00 -07:00

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# Pin Is Pressed
Find whether the pin you say is pressed or not pressed.
If you hold the `GND` pin with one hand and touch pin `0`, `1`, or `2` with the other,
a very small (safe) amount of electricity will flow through your body and back into
the micro:bit. This is called **completing a circuit**. It's like you're a big wire!
```sig
input.pinIsPressed(TouchPin.P0);
```
## ~hint
This function works best when the BBC:microbit is using batteries for power,
instead of the USB cable.
## ~
### Parameters
* a [string](/reference/types/string) that holds the pin name (**P0**, **P1**, or **P2**)
### returns
* a [boolean](/reference/types/boolean) that means whether the pin you say is pressed (`true` or `false`)
### Example
This program shows `1` if `P0` is pressed, and `0` if `P0` is not pressed:
```blocks
basic.forever(() => {
if (input.pinIsPressed(TouchPin.P0)) {
basic.showNumber(1, 150)
} else {
basic.showNumber(0, 150)
}
})
```
### See also
[BBC micro:bit pins](/device/pins), [on pin pressed](/reference/input/on-pin-pressed), [analog read pin](/reference/pins/analog-read-pin), [analog write pin](/reference/pins/analog-write-pin), [digital read pin](/reference/pins/digital-read-pin), [digital write pin](/reference/pins/digital-write-pin)