1 files changed, 82 insertions, 0 deletions
diff --git a/source/lang/pulsein.rst b/source/lang/pulsein.rst
new file mode 100644
index 0000000..7bbe84c
--- /dev/null
+++ b/source/lang/pulsein.rst
@@ -0,0 +1,82 @@
+.. _lang-pulsein:
+
+pulseIn()
+=========
+
+Description
+-----------
+
+Reads a pulse (either HIGH or LOW) on a pin. For example, if
+**value** is **HIGH**, **pulseIn()** waits for the pin to go
+**HIGH**, starts timing, then waits for the pin to go **LOW** and
+stops timing. Returns the length of the pulse in microseconds.
+Gives up and returns 0 if no pulse starts within a specified time
+out.
+
+
+
+The timing of this function has been determined empirically and
+will probably show errors in longer pulses. Works on pulses from 10
+microseconds to 3 minutes in length.
+
+
+
+Syntax
+------
+
+pulseIn(pin, value)
+pulseIn(pin, value, timeout)
+
+
+
+Parameters
+----------
+
+pin: the number of the pin on which you want to read the pulse.
+(*int*)
+
+
+
+value: type of pulse to read: either
+`HIGH <http://arduino.cc/en/Reference/Constants>`_ or
+`LOW <http://arduino.cc/en/Reference/Constants>`_. (*int*)
+
+
+
+timeout (optional): the number of microseconds to wait for the
+pulse to start; default is one second (*unsigned long*)
+
+
+
+Returns
+-------
+
+the length of the pulse (in microseconds) or 0 if no pulse started
+before the timeout (*unsigned long*)
+
+
+
+Example
+-------
+
+::
+
+
+
+    int pin = 7;
+    unsigned long duration;
+
+    void setup()
+    {
+      pinMode(pin, INPUT);
+    }
+
+    void loop()
+    {
+      duration = pulseIn(pin, HIGH);
+    }
+
+
+
+
+.. include:: cc-attribution.txt