micropython · peterhinch · Mar 17, 2016 · Mar 17, 2016 · Mar 17, 2016 · Mar 17, 2016
diff --git a/docs/library/pyb.I2C.rst b/docs/library/pyb.I2C.rst
@@ -63,16 +63,24 @@ Constructors
 
     .. class:: pyb.I2C(bus, ...)
 
-       Construct an I2C object on the given bus.  ``bus`` can be 1 or 2.
-       With no additional parameters, the I2C object is created but not
+       Construct an I2C object on the given bus.  ``bus`` can be 1 or 2, 'X' or
+       'Y'. With no additional parameters, the I2C object is created but not
        initialised (it has the settings from the last initialisation of
       the bus, if any).  If extra arguments are given, the bus is initialised.
        See ``init`` for parameters of initialisation.
 
-       The physical pins of the I2C busses are:
+       The physical pins of the I2C busses on Pyboards V1.0 and V1.1 are:
 
          - ``I2C(1)`` is on the X position: ``(SCL, SDA) = (X9, X10) = (PB6, PB7)``
          - ``I2C(2)`` is on the Y position: ``(SCL, SDA) = (Y9, Y10) = (PB10, PB11)``
+
+       On the Pyboard Lite:
+
+         - ``I2C(1)`` is on the X position: ``(SCL, SDA) = (X9, X10) = (PB6, PB7)``
+         - ``I2C(3)`` is on the Y position: ``(SCL, SDA) = (Y9, Y10) = (PA8, PB8)``
+
+       Calling the constructor with 'X' or 'Y' enables portability between Pyboard
+       types.
 
 Methods
 -------

diff --git a/docs/library/pyb.SPI.rst b/docs/library/pyb.SPI.rst
@@ -33,9 +33,9 @@ Constructors
 
     .. class:: pyb.SPI(bus, ...)
 
-       Construct an SPI object on the given bus.  ``bus`` can be 1 or 2.
-       With no additional parameters, the SPI object is created but not
-       initialised (it has the settings from the last initialisation of
+       Construct an SPI object on the given bus.  ``bus`` can be 1 or 2, or
+       'X' or 'Y'. With no additional parameters, the SPI object is created but
+       not initialised (it has the settings from the last initialisation of
        the bus, if any).  If extra arguments are given, the bus is initialised.
        See ``init`` for parameters of initialisation.
 

diff --git a/docs/library/pyb.UART.rst b/docs/library/pyb.UART.rst
@@ -103,7 +103,7 @@ Methods
 
     .. method:: uart.any()
 
-       Return ``True`` if any characters waiting, else ``False``.
+       Returns the number of characters waiting (may be 0).
 
     .. method:: uart.writechar(char)
 

diff --git a/docs/pyboard/tutorial/assembler.rst b/docs/pyboard/tutorial/assembler.rst
@@ -64,8 +64,8 @@ This code uses a few new concepts:
 Accepting arguments
 -------------------
 
-Inline assembler functions can accept up to 3 arguments.  If they are
-used, they must be named ``r0``, ``r1`` and ``r2`` to reflect the registers
+Inline assembler functions can accept up to 4 arguments.  If they are
+used, they must be named ``r0``, ``r1``, ``r2`` and ``r3`` to reflect the registers
 and the calling conventions.
 
 Here is a function that adds its arguments::