c_meyer/pxt-calliope
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

2.1.28, initiation update to PXT v5.28.24 (#54)

Browse Source
This commit is contained in:
Amerlander
2019-12-02 05:58:26 +01:00
committed by Peli de Halleux
parent 38a964516e
commit 5c114a0c57
1261 changed files with 50692 additions and 21604 deletions
Download Patch File Download Diff File Expand all files Collapse all files

39
docs/reference/pins/pulse-in.md
View File

@@ -1,32 +1,37 @@
# Pulse In
# pulse In
Returns the duration of a pulse (high or low) from a [pin](/device/pins) on
the @boardname@ board in microseconds.
Get the duration, in microseconds, of a pulse (high or low) from one of the pins.
```sig
pins.pulseIn(DigitalPin.P0, PulseValue.High)
```
### ~avatar
## ~avatar
Some pins are also used by the [LED screen](/device/screen).
Please read the [page about pins](/device/pins) carefully.
## ~
### ~ hint
**Simulator**: This function needs real hardware to work with. It's not supported in the simulator.
### ~
### Parameters
## Parameters
* ``name`` is a [string](/reference/types/string) that stores the name of the pin (``P0``, ``P1``, or ``P2``, up through ``P20``)
* ``value`` is the value of the pulse, ``high`` or ``low``
* ``maxDuration``, maximum duration in micro-seconds. If no pulse is received
* ``name`` the name of the pin (``P0``, ``P1``, or ``P2``, up through ``P20``).
* ``value`` the value of the pulse, either ``high`` or ``low``.
* ``maxDuration``, maximum duration to wait for the pulse in microseconds. If no pulse is received, the duration returned is `0`.
### Returns
## Returns
* a [number](/reference/types/number) that represents the pulse duration in micro-seconds
* a [number](/types/number) that is the pulse duration in microseconds.
### Example: Measuring distance with a sonar
## Example: Measuring distance with a sonar
The following script sends a pulse on ``P0`` and reads the pulse returned by a HC-SR04 sonar to determine the distance of the object in front of the sensor.
Send a pulse on ``P0`` and read a pulse returned by a HC-SR04 sonar ultrasonic sensor. The sensor determines the distance of the object in front of it.
```blocks
basic.forever(() => {
@@ -43,12 +48,6 @@ basic.forever(() => {
})
```
#### ~hint
## See also
This function is not supported in the simulator.
#### ~
### See also
[digital write pin](/reference/pins/digital-write-pin),
[digital write pin](/reference/pins/digital-write-pin)