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diff --git a/docs/wipy/general.rst b/docs/wipy/general.rst
index 0991dbaeaf..0d0327f4b3 100644
--- a/docs/wipy/general.rst
+++ b/docs/wipy/general.rst
@@ -179,3 +179,56 @@ Details on sleep modes
 * ``machine.sleep()``: 950uA (in WLAN STA mode). Wake sources are ``Pin``, ``RTC``
   and ``WLAN``
 * ``machine.deepsleep()``: ~350uA. Wake sources are ``Pin`` and ``RTC``.
+
+Additional details for machine.Pin
+----------------------------------
+
+On the WiPy board the pins are identified by their string id::
+
+    from machine import Pin
+    g = machine.Pin('GP9', mode=Pin.OUT, pull=None, drive=Pin.MED_POWER, alt=-1)
+
+You can also configure the Pin to generate interrupts. For instance::
+
+    from machine import Pin
+
+    def pincb(pin):
+        print(pin.id())
+
+    pin_int = Pin('GP10', mode=Pin.IN, pull=Pin.PULL_DOWN)
+    pin_int.irq(trigger=Pin.IRQ_RISING, handler=pincb)
+    # the callback can be triggered manually
+    pin_int.irq()()
+    # to disable the callback
+    pin_int.irq().disable()
+
+Now every time a falling edge is seen on the gpio pin, the callback will be
+executed. Caution: mechanical push buttons have "bounce" and pushing or
+releasing a switch will often generate multiple edges.
+See: http://www.eng.utah.edu/~cs5780/debouncing.pdf for a detailed
+explanation, along with various techniques for debouncing.
+
+All pin objects go through the pin mapper to come up with one of the
+gpio pins.
+
+For the ``drive`` parameter the strengths are:
+
+  - ``Pin.LOW_POWER`` - 2mA drive capability.
+  - ``Pin.MED_POWER`` - 4mA drive capability.
+  - ``Pin.HIGH_POWER`` - 6mA drive capability.
+
+For the ``alt`` parameter please refer to the pinout and alternate functions
+table at <https://raw.githubusercontent.com/wipy/wipy/master/docs/PinOUT.png>`_
+for the specific alternate functions that each pin supports.
+
+For interrupts, the ``priority`` can take values in the range 1-7.  And the
+``wake`` parameter has the following properties:
+
+  - If ``wake_from=machine.Sleep.ACTIVE`` any pin can wake the board.
+  - If ``wake_from=machine.Sleep.SUSPENDED`` pins ``GP2``, ``GP4``, ``GP10``,
+    ``GP11``, GP17`` or ``GP24`` can wake the board. Note that only 1
+    of this pins can be enabled as a wake source at the same time, so, only
+    the last enabled pin as a ``machine.Sleep.SUSPENDED`` wake source will have effect.
+  - If ``wake_from=machine.Sleep.SUSPENDED`` pins ``GP2``, ``GP4``, ``GP10``,
+    ``GP11``, ``GP17`` and ``GP24`` can wake the board. In this case all of the
+    6 pins can be enabled as a ``machine.Sleep.HIBERNATE`` wake source at the same time.